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Astronomical Observatories of Kazan Federal University

Date of Submission: 11/12/2020
Criteria: (i)(ii)(iv)(vi)
Category: Cultural
Submitted by:
Permanent Delegation of the Russian Federation
State, Province or Region:
Republic of Tatarstan
Ref.: 6494

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Property names are listed in the language in which they have been submitted by the State Party


KFU Astronomical observatory: N55 47 27 E49 07 09 
V.P. Engelhard Astronomical observatory: 55 50 3 E48 51 00

The Astronomical Observatories of Kazan Federal University represent an ensemble of the Kazan Observatory and a complex comprising a suburban Observatory, its historical buildings, museum exhibits, a culture and presentation complex of the Planetarium and an astrological park. The former is located in the central part of Kazan. The latter – in Zelenodolsky district of the Republic of Tatarstan, in the north-east of the European part of the Russian Federation.

The properties proposed for inscription on the list are directly related to the events of the outstanding universal value. The advent of a fundamental celestial coordinate system allowed us to clarify astronomical constants and address fundamental, cosmological issues of the emergence and evolution of the Universe. Also, the accumulation of data on the Sun laid the groundwork for a deeper understanding of the processes occurring on the Sun and other stars and helped to predict solar activity which had a direct impact on the process of evolution on Earth.

The astronomical properties presented for inscription on the Russian Federation Preliminary List are a complex nomination comprising several components: the Observatory of Kazan Imperial University (19th century) located in the historical center of Kazan, in the courtyard of the main building of the University, and the Engelhardt Astronomical Observatory (1901) designed specifically for large-scale observations and studies under the conditions most suitable for night observations 24 km west of Kazan (countryside, its height is 94 m above the sea level). The properties possess the outstanding universal value being historical monuments and advanced centers for development of astronomy in the Russian Empire, the USSR, the Russian Federation, Eastern Europe and Eurasia, where innovative and technological breakthroughs took place in the 19th and 20th centuries. Today they continue to expand the horizons of regional, European and international science. The properties of Kazan Federal University are the monuments of federal significance. Kazan University has been recognized as a particularly valuable cultural heritage site of the peoples of the Russian Federation since 1997.

The Department of Astronomy that was founded by Joseph Johann Littrow at the Imperial University of Kazan in 1810 became the basis for the development of astronomy, quite advanced for that time, and led to the establishment of the Astronomical Observatory at the University in 1814 (first located in temporary buildings, later in its permanent building built in 1833-1837) and the Engelhardt Astronomical Observatory in 1901.

Both observatories are unique monuments of science and technology. The activity that took place there within a wide range of research in various fields of astronomy triggered important changes in science and development of technologies in Eastern Europe and Eurasia over a 200-year period. The achievements, research, discoveries made in the observatories testify not only to the development of scientific and astronomical knowledge in Russia, but also to close cooperation with a number of Western European countries in science, technology, culture, as well as the enormous contribution of the scientists of Kazan University to international astronomy.

November 11, 1814 can be considered the genesis of professional astronomy in Kazan when a young energetic Austrian professor J.I. Littrow made a small observatory on top of a stone building in the University Botanical Garden (designed by P.M. Vasiliev). A tower for the equatorial telescope was built above the building, a span was made for the meridian circle, and a small house with a retractable roof was built for small-scale equipment. In 1822, the Observatory was temporarily located in a wooden gallery – an extension to the so-called ‘Spizharny’ House, which had previously belonged to the merchant Spizharnaya (at the corner of Astronomicheskaya and Kremlyovskaya streets), which at the time described was part of I. Simonov’s apartment since the Observatory, built by Littrow, fell into disrepair due to its decay.

Musin-Pushkin, who came in charge of Kazan educational district in 1827, ordered I. Simonov to draw up a plan for the future astronomical observatory. Simonov defined the aims of the Observatory as follows: 1) to work for the benefit of science and 2) to promote domestic astronomical education. The building plan of the Astronomical Observatory was chosen according to the aims. The University courtyard was chosen as the site for the Observatory. It met all the requirements: it was high, dry, with an open horizon in all the directions. The foundation stone was laid in 1833 and construction was completed by the end of 1837. A 9-inch refractor, a meridian circle, heliometers and other astronomical equipment were installed. Regular observations started at the Observatory.

The properties of the Kazan University Astronomical Observatory to be inscribed on the UNESCO Heritage List:

  1. The building of the Astronomical Observatory on Vienna meridian circle (1837);
  2. The unique genuine instruments of the 19th century (Merz refractor produced by Fraunhofer ( D=9-inch, F=4 m) (1838); Rapsold Heliometer; George Dollond astronomical tube; Vienna meridian circle; Equatorial telescope; Transit instrument; precise clock (functioning since February 23, 1885).

The history of the creation of the Engelhardt Astronomical Observatory begins with the donation of unique astronomical equipment by the famous astronomer Vasily Engelhardt from his private observatory in Dresden to Kazan University in 1897. Having ceased his astronomical activities due to advanced years and poor health, Engelhardt decided to donate all his equipment and the library to the Kazan University Astronomical Observatory on condition that his equipment should be used for observations as soon as possible. In 1898, by a decree of the Emperor, funds were allocated and a site for the construction of the Astronomical Observatory was allotted.

A 21-hectare plot was allocated by the Forest Department from the State-owned Paratskaya dacha at a distance of 1 km from Lavrentievo Station of the Moscow-Kazan Railway. In June 1901, the station was renamed into Observatory Station. On March 7, 1899, construction began, and on September 21, 1901, the grand opening of the Kazan University Astronomical Observatory took place. In 1903, it officially received the name of Engelhardt.

The Engelhardt Astronomical Observatory properties to be inscribed on the UNESCO Conservation List:

  1. The main administrative building of the EAO;
  2. The main building of the EAO;
  3. The EAO library building;
  4. The Heliometer Pavilion;
  5. The South Mark - the tomb;
  6. The Northern Mark;
  7. Range of the 19th – 20th centuries tools.

The terrain of the site is absolutely flat; its height above sea level is 94 m and above the Volga River – 55 m. With its eastern side, the site adjoins the road going from the station and is separated from it by a long fence. The gates to the Observatory are located on the eastern side of the site. Not far from the gates, there is an administrative two-story elegant stone building in the style of early classicism. The architect of all the buildings on the territory of the Observatory was the university architect N. Malinovsky. The building holds the director’s office, laboratories, computing services, etc. In the early 20th century, there were apartments for observers in the eastern wing. A meteorological station was previously located south of the building. From the entrance gate to the west, a wide alley leads to the Observatory building, with the front facing south.

Above the wide stone porch is the inscription: 1901 (time of construction). The Observatory building is a one-storey stone building; in its central part there are two halls; at the end there is a tower for the 12-inch telescope of the Engelhardt equator from the west, and from the east, it is connected by a small corridor to the pavilion of the meridian circle. The total length of all the three buildings is 40 meters. The height of the tower to the top of the dome is 11 meters, the height of the central building is 6 m and the height of the meridian hall is 7 m. The external architecture of the central building and the tower is very light and elegant. The Meridian Hall was built by the design of Professor W. Schleier from galvanized corrugated iron. The walls of the hall are double with an air gap of 0.4 m for air circulation. On the southern and northern sides of the pavilion are 1.2 m wide hatches for observations. On the south side of the property is the Library building - a beautiful stone building with columns that forms an almost regular triangle with two buildings mentioned above.

The main instrument of the Engelhardt Astronomical Observatory was a 12-inch Engelhardt refractor, built by the English master Grubb in 1875. It has a lens with the diameter of 31 cm, about 4 meters long. The tower in which it is located is 6.5 m high; its inner diameter is about 6 m. The tower is surrounded by a small balcony with a fine cast-iron railing. The column for the refractor is laid out separately from the walls of the tower and goes underground for 3 meters. The iron dome is lined with wood, it moves on rollers that run along two pairs of rails. The diameter of the dome is 6.6 m. It has a one-meter wide slot for observation, which closes with two hatches.

The Meridian Circle of the Engelhardt Observatory was made in 1845 in Hamburg by the famous designer of astronomical instruments - Repsold. The instrument columns are 2 meters above the hall floor and insulated from the rest of the foundation and the floor with glycerin. The distance between the columns is 1.1 m. The meridian circle is covered with a wooden sliding house for protection against heating. At the meridian circle, there are two marks, each 130 m away from the center of the Mercury horizon. In the north of the territory in the direction of the meridian, there is the iron pavilion of the Northern Mark. Due to the lowering of the terrain, the Southern Mark had to be raised by filling a special mound 5.5 meters high. The Mark Pavilion is not only an astronomical point, but also a tomb - a unique architectural structure. It is built in the form of a small chapel in the Byzantine style, decorated around the perimeter with stars and zodiac signs. At its base is a crypt for two people, intended for V. Engelhardt and D. Dubyago. At first, only Dubyago, who died in 1918, rested there. The body of V. Engelhard, who died in Dresden in 1915, could not be transferred to the Observatory due to the outbreak of World War I with Germany and the ensuing revolution. However, the astronomers of the Engelhardt Observatory did not lose hope of fulfilling the last will of their founder and burying his ashes under the southern Mira - the tomb, next to his friend. In September 2014, the will of the famous astronomer was fulfilled. After lengthy and successful negotiations with his descendants, the coffin with the ashes of the scientist was transported to the place of his reburial - the Engelhardt Astronomical Observatory.

A unique instrument of the Engelhardt Astronomical Observatory is the only heliometer telescope currently operating in the world. It is one of the first heliometers coming out of Repsold's workshops. It was made in 1874 and installed at the Engelhardt Observatory in 1908 in a specially built round pavilion, 3.6 m in diameter.

Moreover, the contemporary telescopes purchased in the United Arab Emirates in different times are located in the observing site of the Engelhardt Astronomical Observatory. They are as follows: zenith telescope, Gade astrograph, meniscus telescope of Mascutov system, AFR, telescope AZT-14, modified and completed by CCD-matrix and others.

The Engelhardt Astronomical Observatory has a big specialized library stock with 100,000 storage units. The libraries of V. Engelhardt, A. Kovalsky, D. Dubyago and M. Grachyov, which contain rarities signed by famous astronomers, form the foundation of the stock.

The scientific equipment of the observatory supports the astronomical exploration at the modern level contributing much to the world astronomy. The scientists set up Fundamental Coordinate at Transit circle and made up the catalogues of faint stars.

The longest sets of observation in Russia were received on the heliometer.  The scientists took sight on the Moon and stars and made up the catalogues of the lunar craters. The coordinate’s determination for solar system bodies was made with the help of dioptric telescope. The astrophysical department has been exploring interstellar gas and the Galaxy structure.

The catalogue of spectral quantities and collision indexes of more than 30,000 stars was made up. In 1932, the Observatory was chosen to be the center on variable stars exploration. The Meteoric department of the Observatory is working at the international level. The glass library numbers about 50,000 photo plates.

The area of the Engelhardt Observatory looks like a park with rare trees – hundred-year-old cedars and oaks, chamomile meadows fit into its landscape with the buildings and pavilions. The picturesque lake “Ochky” (glasses) is located in the north-west. It is the system of two lakes (natural and artificial ones) connected by a small canal. Every year thousands of students and tourists visit the Engelhardt Observatory in order to learn and see the astronomical heritage of the observatory in which cultural, scientific and educational components are joined.

The Engelhardt Astronomical Observatory has a museum of Astronomy History with many unique historical, scientific and art exhibit items. In April 28, 2013 the modern educational and cultural campus “Planetarium of Kazan Federal University and Astronomical Park” was launched to popularize astronomy and make it challenging and easily understood for pre-school and school children and get them interested in further professional learning. Here scientific conferences of the international and all-Russia levels are held regularly. Journalists of radio and television write about the Observatory. Here they find interesting themes for their projects and the best sceneries for their historical and cultural performances.

The Astronomical observatories of Kazan Federal University are the only scientific, educational and cultural centers that are located between Moscow and the eastern borderline of Russia.

Buffer zone of the nominated properties

The Engelhardt Astronomical Observatory

The Kazan University Astronomical Observatory, built in 1899-1901, was located 20 km from Kazan on the site of Krasnogorsk-Turinsky forest estate and 2 km from Lavrentievo Railway Station (renamed as Observatory Railway Station shortly after its construction).

The Observatory is located 50 m from the edge of the plateau of the third floodplain terrace, separated from the second (under the meadow) terrace descending towards the Volga by a high steep slope. The slope of the terrace and the entire area around the Observatory are covered with mixed forest. The central site of the Observatory complex is cleared of vegetation; it has a flat terrain with a slight slope. On the eastern side of the Observatory complex there is a highway that connects Gorky highway with the Observatory Railway Station and a village of the same name located on the Volga bank. The railway passes under the slope, along its foot, at a distance of 1 km in the west-east direction, parallel to the Volga. The height of the slope is 10-12 m.

Visually, the territory of the Observatory complex is hidden behind the tall vegetation of the forest. The towers of the telescopes, the domes and the hill with the southern tomb chapel are small in height. They are the local dominants of the complex.

The principle of ‘dissolution’ in the natural landscape was laid down initially in the construction project by the architect Malinovsky. On the 1910 plan, compiled by the land surveyor E. Gornostaev, vegetation with paths and a path network was especially carefully displayed. The surrounding “deciduous forest with single oaks” smoothly joins the landscape “park with single oaks”; the park and the forest do not have a clear border.

The boundaries of the Engelhardt Astronomical Observatory have not been defined.

The boundaries of the territory of the property are proposed to be determined in accordance with the cadastral boundaries of the Engelhardt Astronomical Observatory, as historically established.

In accordance with the Russian law, buffer zones are established for the cultural heritage properties if their cultural zones have not been defined. This measure ensures the safety of the cultural heritage properties as well as their composition and specific features (panoramas). Within the boundaries of the buffer zones, the construction of capital facilities or their reconstruction connected with a change in their parameters (height, number of floors, area), with the exception of the construction and reconstruction of linear facilities, is prohibited. Buffer zones of ensembles and complexes must be established at a distance of 200 m from the boundaries of the cultural heritage property.

However, taking into account the requirements of the Operational Guidelines for the Application of the 1972 UNESCO Convention which states that the buffer zone should include the immediate surroundings of the nominated property, important features (landscapes) and other territories or attributes that are functionally important for the property and its protection, it is proposed to expand the Observatory buffer zone to the south up to the foot of the hill and to the west to the clearing.

Justification of Outstanding Universal Value

The Astronomical Observatories of Kazan Federal University (KFU) are historical and cultural monuments - values of outstanding universal importance associated with astronomy (observatories, individual architectural structures, outstanding observations and research), proposed for inclusion as part of the thematic initiative “Astronomy and World Heritage”.

The Astronomical Observatories of KFU are directly related to two events of outstanding universal value in astronomy of the 19th-20th centuries. The first is the creation of a celestial Fundamental Coordinate System, which specifies astronomical constants and solves fundamental, cosmological issues of the emergence and evolution of the Universe. That largest international event, first in the history of astronomy, was made possible due to the observation and determination of the stars’ coordinates made in many observatories of the world over a period of about 200 years. Using telescopes of original shapes and designs, millions of individual observations were obtained, on the basis of which, through collective efforts, a high-precision coordinate system was created in the form of a series of five fundamental FK catalogs. Starting with 1935 this system has been used as the basis of the system of axes for astronomic and geodesic works in the world.

The other issue developed at the KFU Astronomical Observatories and the results of which made a great contribution to the development of world astronomical science is the study of the Sun. Studying the central star of our solar system allows us to better understand the processes occurring on the Sun and other stars, and to predict solar activity, which has a direct impact on the evolution of civilization on Earth. Data on the structure, composition and evolution of the Sun, and the effect of solar activity on the Earth obtained from long-term observations at many observatories make it possible to conduct the Solar Weather service necessary for the Earth civilization activity nowadays. These studies were carried out mainly on Repsold heliometers in two KFU observatories. Currently, the instrument located in the Engelhardt Astronomical Observatory is the only active heliometer telescope in the world.

The solution of these unique, complicated and long-term scientific problems, connected with the world culture of our society was accompanied by the development of selected architectural forms in constructing unusual astronomical observatories for observing stars and individual structures (pavilions and towers) together with landscape environment to provide astronomical observations. In fact, astronomical observatories are outstanding architectural monuments of specialized astronomic scientific complexes (ensembles) the use of which has led to no less outstanding scientific achievements. On the example of observatories, historical and culture monuments, we can retrace the development of typology for big and small architectural forms in astronomy of the 19th-21st centuries. Preserving of observatories as historical, cultural monuments and scientific monuments is connected with preserving of unique old astronomical instruments and devices of global importance.

At the same time, in order to address the important issues of astrophysics and also common scientific issues such as the Universe evolution or the origin of chemical elements, we need information that can only be obtained by studying stars. It is in the stars that a large part of visible mass of the Universe is concentrated, and, from this point of view, stars are the main objects in space. A very important and, in most cases, the only source of information about physical processes on stars is their radiation. Star radiation in a wide spectral range, from far ultraviolet to infrared, is formed in a thin surface layer called the star’s atmosphere. Astronomer of Kazan University N. Sakhibullin, in the early 1970s, for the first time in the former USSR, implemented a new approach to the analysis of stellar spectra, based on the rejection of the hypothesis of local thermodynamic equilibrium (non-LTE task - multi-parameter and non-linear). Therefore, although most spectroscopists recognize the importance of taking deviations from LTE into account when determining the physical parameters of stars, so far the non-LTE approach has been mastered only in a few astrophysical centers in the world: in Germany, France, the USA, Italy, Japan, Ukraine, and Russia - only at Kazan University. Sakhibullin was the first in the USSR to analyze the spectral lines of MgII, CII, CIII, and CIV in hot stars. For the first time, the kinetic equilibrium of the CIII ion was considered and the mechanism of the appearance of emission in the infrared lines of this ion was explained.

Under his supervision the exploration was expatiated to the absorptions of other atoms and ions and also to the stars in a broad diapason of parameters (with effective temperatures from 5000 K to 55000 K.). Together with his colleagues he studied the emission origin in the NIV 4057 A line for the stars of spectral class O (L. Mashonkina), the problem of Na excess of F supergiant (N. Sahibullin in cooperation with the scientists of the Crimea astrophysical observatory), explored the mechanism of superionization and enforcement of the lines FeI in the spectrum of solar burst (N. Sahibullin and U. Bayazitov).

Today, traditional directions for Kazan astronomy continue to develop: astrometry, selenodesy, celestial mechanics, and astrophysical studies occupy an important place. The staff of the Department of KFU observatories are members of the International Astronomical Union and the European Astronomical Society.

The observatory is an educational center where excursions are held annually for schoolchildren, teachers, domestic and international scientific community, tourists from all over the world.

The important role of Kazan astronomy is noted by the world astronomical community.

Criterion (i): The Astronomical Observatories of Kazan Federal University are a site that embodies a continuous thread of history, science and culture from its pioneering work in the development of astronomy, astrophysics, space geodesy in the 19th - early 21st centuries to the present day.

Observatories as a “collective instrument” are a masterpiece of human creative genius, demonstrating revolutionary achievements both in science and in engineering and technology.

The Kazan Observatory was founded, began to function successfully and made a huge contribution to the development of astrophysics, geodesy and astronomy only through persistence and faith in the idea of ​​the exceptional astronomical science of Kazan University representatives. The founder of the oldest department of astronomy in Russia, Joseph Littrow, the ideological inspirer of creating the observatory, initially made observations in temporary buildings, waiting for the allocated funding. Ivan Simonov was directed by the trustee of the Kazan educational district Mikhail Musin-Pushkin to design the permanent building of the observatory and take the lead with its construction. It inspired a new life in the ​​developing an astronomical school in Kazan and introducing practical knowledge and skills for the university students who had already been studying theoretical astronomy. It is interesting to know that in 1836, when the building was in a base condition, Kazan was visited by Emperor Nicholas I. Temporary floors were laid in the observatory, and the Tsar could have enough time to admire the city and its surroundings from the upper terrace. The result of this visit was an additional allocation of 15,000 rubles for the purchase of tools.

According to the initial plan of Simonov, on the roof of the building where a spiral staircase leads from the inner room, there was not supposed to be a large mobile tower, because Kazan University did not hope to obtain a large refractor soon, but Nicholas I, while getting acquainted with the plan of the Kazan University observatory, in his own hand wrote on the report: “A tower must be like in Derpt (nowadays Estonian Tartu)” and added a significant amount of money from the state treasury to the cost estimates. The construction of this and the other two small towers was commissioned to the university mechanic Ney, a student of the famous Reichenbach, invited from Germany in 1829 by Simonov on the recommendation of Littrow. According to the report of the Kazan University Construction Committee, the total amount of construction of the observatory cost 78,790 rubles 53.75 kopecks in banknotes, or 22,511 rubles 58 kopecks in silver. Simultaneously with the construction of the observatory, a 9-inch refractor was commissioned in 1835 at the Fraunhofer workshop (Munich, Germany). It was ready in August 1837 and a year later it was finally installed in the main mobile tower. Simonov went to St. Petersburg in September 1837 to receive the refractor. Having received it from Germany, Simonov drove the lens himself, and sent the refractor with a special official. This refractor was then one of the few outstanding instruments and cost the treasury 36,000 rubles in banknotes, and for the 15,000 rubles allocated by Emperor Nicholas I, 4 more large instruments were purchased.

The observatory of Kazan University in its design and equipment had stood in one row with the best observatories in Europe. Until 1840, Simonov was its only observer, combining numerous observations with large teaching load, because astronomy at Kazan University then "was taught in a very wide range." According to Dmitry Dubyago, “in general, following the life of this remarkable person, one involuntarily marvels at the diversity of his scientific studies, which is shown both by his works on pure mathematics, astronomy, magnetism, etc., and an extraordinary zeal for making observations. He himself writes, for example, that he made hourly meteorological observations day and night, forcing to wake him up hourly during sleep: once - for 60 days (!), another time - for 30 days. And he did not miss a single hour (!). Similarly, without anybody’s help, he observed changes in magnetic declination many times for 44 hours at a time”.

In 1819 Simonov was invited as an astronomer to the famous round-the-world expedition of Faddey Bellingshausen and Mikhail Lazarev, culminating in the discovery of a new continent, Antarctics. Simonov’s duties on this expedition included getting a fix on the location of the newly discovered islands. One of them subsequently was named after him. Opened in 1820, the Simonov (Tuvana-Itolo) island is an uninhabited island in the Pacific Ocean, south of the Fiji archipelago (21 ° 2'55 '' S and 178 ° 46'23 "E), today belongs to the UK. Its length is 1.85 km, width is about 1 km. In addition to getting a fix on the location of islands, Simonov carried out oceanographic, oceanological and climatological observations, collected and brought from the countries of the Southern Hemisphere rich natural-historical collections, which today are part of the astronomical, historical and ethnographic museums of Kazan Federal University.

Ivan Simonov began teaching at university in 1814 after conferring upon him the title of adjunct of the physical and mathematical sciences. From 1814 to 1816 he taught practical astronomy, as well as geodesy under the general supervision of J. Littrow. After his departure, Simonov was entrusted with the teaching of practical astronomy, teaching students to work on instruments and maintaining a journal of observations. At 22, after conferring the title of extraordinary professor I. Simonov also began to teach theoretical astronomy. In the absence of I. Simonov teaching of astronomy at the university did not stop. Lectures were given by Nicolas Lobachevsky, who until the end of his life retained his love of astronomy and, as a rector, contributed a lot to its development at the university.

In 1847, I. Simonov was approved as the rector of the university. Therefore, in 1850, Marian Kowalski (1821-1884), invited from the Pulkovo Observatory, was appointed an associate professor in the department of astronomy. The observatory was entrusted to the observer astronomer Mikhail Lyapunov.

Kowalski created new methods of calculating the orbits of minor planets and binary stars, remarkable in their idea. But his most important work, On the Laws of the Own Motions of the Stars of the Bradley Catalogue, is devoted to solving a very difficult problem, the study of the proper motions of stars. It developed and applied a new method for determining the motion of the solar system in space. The first developer of this method was M. Kowalski, only decades later he received its scientific proof and is now known as the Kowalski-Erie method. In addition, a mathematical formulation of the problem of galactic rotation, the existence of which was finally established only in 1927, and the theory of the central position of the Sun in the Galaxy was thoroughly refuted.

Another bright personality who contributed to the development of astronomical science was a graduate of Kazan University M. Gusev, who later became director of the Vilna Observatory. He was the first in Russia to apply the photographic method to the study of celestial phenomena, in particular, the surfaces of the Sun and the Moon, and organized a photographic service for observing sunspots. The first astrophysicist of Russia, Matvey Gusev also made a significant contribution to the study of the moon shape, using a mathematical method based on accurate measurement of lunar photographs. He established the elongation of the moon shape in the direction toward the Earth. One of the craters of Mars is named after him, in which, by the way, in 2004 Mars rover Spirit landed and carried out a number of interesting studies.

In the work of the department of astronomy in 1850-1854, student Ilia Ulyanov, the future father of Vladimir Lenin, took an active part. As a student, he defended his thesis “Determination of the orbit of Klinkerfus comet”, which received a very flattering review by M. Kovalsky "Mr. Ulyanov comprehended the essence of astronomical observations, which, as you know, often require special considerations and techniques".

The final formation of the Kazan Astronomical School is associated with the name of Dmitry Dubyago (1849-1918), who was appointed professor of astronomy in Kazan and director of in-town observatory after the death of M. Kowalski on May 28, 1884. The period of the direction of D. Dubyago is a turning point in the work of the Kazan Astronomical Observatory.

The impossibility of the isolated productive work of the observatory without constant strong communication with other observatories of the world was acutely recognized even by the builder-director professor I. Simonov. He began to establish such a connection in his trips abroad, and professor M. Kowalski continued this line by participating in international zone observations.

Dubyago widely opened the doors of the observatory for talented youth. A further formation of the pool of young scientists is taking place around the observatory. Graduates of this school not only expanded the creative work of the Kazan Observatory, but also joined the ranks of scientists of other observatories. The increase in staff allowed expanding the observations of the site. Observations develop, and the same is going on with research; a computer bureau is being created at the observatory, a systematic publication of scientific papers is being organized. Since 1893, these works began to appear under the general title "Proceedings of the Astronomical Observatory of Kazan University."

Since February 23, 1885, a clock showing the exact Kazan average time was displayed in the window of the department. For more than half a century, Kazan had synchronized their clocks upon it: as signals of the exact time did not exist then.

At this time, the observatory had excellent instruments: a refractor, a meridian circle, a transit instrument, a heliometer, and the staff of the observatory, in addition to the director, consisted only of amateur astronomer Platon Poretsky and passed assistant A. Kowalski. Therefore, Dubyago considered attracting talented youth to astronomical observations as a matter of paramount importance. Alexander Krasnov, Mikhail Grachev, Yakov Kornukh-Trotsky stayed to work at the observatory. A transit instrument was put into operation; observations on a heliometer to study the physical libration of the moon were started. They were carried out by Alexander Krasnov (1866-1911), a pioneer of heliometric measurements in Russia, who from 1895 to 1898 performed 112 measurements of Mösting Alunar crater. In 1898, A. Krasnov was invited to Warsaw as a professor of astronomy, where he founded the Warsaw Astronomical Observatory. His name was given to a crater on the surface of the Moon.

The Kazan Observatory from 1892 to 1901 carried out pioneering observations on the variability of latitude. Processing of these observations showed that the latitude of the Kazan Astronomical Observatory varied up to 0.5 ". This corresponds to the pole moving on the Earth's surface by only 16 m. The high accuracy achieved while doing this indicates the good quality of the transit instrument, the good skills of the observers, and the large number of observations made. In Moscow, systematic observations of the variability of latitude were started in the same year as in Kazan, and at the Pulkovo Observatory it was done 12 years later.

In addition, D. Dubyago contributed to providing a scientific and literary base for research. He understood that fruitful research work could be carried out only when supported by a good library. The observatory had little money, and it was impossible to purchase all the necessary books. At the beginning of the directorship of D. Dubyago, the library of Kazan In-Town Astronomical Observatory was in its infancy. There were only 875 books, odd and random. The task was to create a library corresponding to the scientific tasks of the astronomical observatory, and to make the flow of books into it continuous and systematic. Therefore, in the absence of funding D. Dubyago proposed an original and effective idea: all observatories to start the exchange of publications. Thus, on January 1, 1917, the library had already had 9,000 volumes.

Diverse scientific discoveries made due to the magnificent intellectual, scientific potential, charismatic and strong-willed personalities of N. Lobachevsky, I. Simonov, M. Kovalsky, D. Dubyago and others made a huge contribution to the development of world astronomical science. The masterpiece of the human genius of Kazan astronomers was not only the in-town astronomical observatory, but also the second one, built in 1901 out of town in order to exclude exposure to the light of the central part of the city, which began to interfere with work of in-town   observatory. Handing over to Kazan University the unique instruments of his private observatory in Dresden in 1897 by the famous Russian astronomer Vasily Engelhardt was the impulse for creating the observatory. So, the Grubb refractor, owned by V. Engelhardt, in the 1880s was one of the best in Germany, and by the end of the 1890s, when Engelhardt decided to retire, it was a wanted acquisition for any observatory. Many observatories of Germany and Russia claimed these instruments, but V. Engelhardt bequeathed them to Kazan University. Such personal factor as friendship with D. Dubyago gave a new impetus to the development of science.

Engelhardt wished that his observatory, which had arisen on German soil, would return to the bosom of his motherland, Russia, and be used in the best way. Initially, he thought of transferring his observatory to one of the southern Russian universities. But, in the end, his choice settled on Kazan University, where his friend Dmitry Dubyago worked.

Dubyago complained often in letters and at face-to-face meetings in Dresden to a friend about severe inconvenience when observing at in-town observatory located in the courtyard of the university in the center of Kazan. Undoubtedly, the friendship with Dmitry Dubyago played a decisive role in the fact that it was Kazan University that Engelhardt decided to transfer all the equipment to his observatory. Despite the fact that the climate of the Volga region was not very favorable to accurate astronomical measurements, Vasily Engelhardt believed that in the friendly hands his observatory would be reborn in the best way. Thus, Engelhardt transferred all his instruments, library and all property (subsequently) to the full disposal of Kazan University. D. Dubyago understood that this was a serious argument in favor of applying for the construction of a new observatory, quite remote from the city. August 29, 1897 V. Engelhardt, through D. Dubyago, enters the Kazan University Council with a petition to accept from him the most important instruments of his observatory as a gift: 12”Grubb equatorial, 6” equat-comet finder, 4”small comet finder, Bamberg transit instrument, Fenel universal instrument, Knoblich clock and Tide watches and a number of other small instruments and devices, as well as his rather significant library of up to 2000 volumes. The gift, of course, was gratefully accepted, and already in December, astronomical instruments in twenty boxes arrived in Kazan. In the summer of 1898, the request of D. Dubyago at the higher instances for the release of funds for the construction of a new observatory and for the allotment of land was granted. Vasily Engelhardt did not stop at that point. Later, by the will, after his death, he and all his property, tangible and intangible, together with capital, with few exceptions, was transferred to Kazan University so that his observatory in its new place would be provided with funds for further development.

Until the end of his days, Vasily Engelhardt took the most passionate part in the construction of a new observatory at Kazan University. The observatory was named after him, Engelhardt.

Criterion (ii): The main research line at the Engelhardt Astronomical Observatory is to explore the coordinate and time issues of astronomy and geodesy, to identify the exact positions of stars and to catalogue stellar positions, to observe and specify the figures and orbits of the bodies of the solar system, to identify galactic parameters, to study astronomical instrumentation and the history of astronomy. The contribution of the Astronomical Observatories of Kazan University is 18 high-precision meridian and photographic catalogues of the positions of stars (including IRSC, Photographic Sky Survey, Catalogue of Weak Fundamental Stars, Photographic Catalogue, Catalogue of Weak Stars, etc.).

The Kazan University astronomical observatories conduct research in various fields of astronomy and demonstrate important changes in the development of science and technology in Eastern Europe and Eurasia for over 200 years. The nominated sites demonstrate both a high level of scientific astronomical expertise and close cooperation with the countries of the Western Europe in science, technology, culture, which also contributed to the development of society in other fields.

Criterion (iv): The architecture of the Kazan University Observatory is an example of a well-preserved building of the 19th century, in its original form, with the main facade oriented to the south-west and halls located in it along the concave arc with an access to the terrace encircling the Observatory building. The main hall was intended for receiving visitors and storing portable instruments, the eastern hall was intended for observing stars in the 1st vertical, and the western one was intended for observing stars in the meridian. Two corner rooms adjoined these halls on each side, through which stone pillars passed from the ground into small roof towers. Nowadays lecture halls are located in these halls, so students absorb the spirit of a two-century history of observations and breakthroughs made within the walls of the Kazan Observatory. On the roof of the building in a large mobile tower there is a 9-inch Fraunhofer refractor (1837). At that time the refractor was one of the outstanding tools. With the funds allocated by Emperor Nicholas I, 4 more large instruments were purchased. In the first half of the XIX century the Observatory of Kazan University in terms of its design and equipment was considered one of the best observatories in Europe and Asia.

The Engelhardt Astronomical Observatory and its property, such as buildings, its territory, a scientific site with the surrounding landscape and habitat, represent a single ensemble (complex). It has an outstanding universal value and cultural, architectural and scientific significance for the history of the eastern European region in the 19th-21st centuries. The activities of astronomical observatories played a significant role in the development of navigation, mapping and the economic development of Russian regions. The nominated astronomical observatories also demonstrate the creation and development of a typology of original architectural forms in Russia, Eastern Europe and Eurasia, namely large forms (original structures of buildings and complexes for astronomical and technological purposes) and small architectural forms (astronomical pavilions, towers, foundations, tools ) in astronomy.

Criterion (vi): The nominated properties are associated with the events of outstanding universal value. The creation of a fundamental celestial coordinate system allows us to specify astronomical constants and to address fundamental, cosmological questions of the origin and evolution of the Universe; the accumulation of data on the Sun provides a deeper understanding of the processes occurring on the Sun and other stars.  Moreover we can predict solar activity which has a direct impact on the evolution of civilization on Earth.

The astronomers of the Kazan Observatory made scientific breakthroughs decades ahead of their time. Thus, the famous scientist, mathematician, one of the founders of non-Euclidean geometry (a masterpiece of human genius), rector of Kazan Imperial University N. Lobachevsky (1827-1845) being fond of astronomy and professionally engaged in astronomy, in his printed report on a trip to Penza after observing the complete eclipse of the Sun (July 26, 1842) developed ideas about the possibility of the dual nature of light almost a century ahead of his era. Light is both the vibration of the ether and the movement of the smallest particles. That expedition marked the beginning of many subsequent trips of Kazan scientists to observe total solar eclipses.

Statements of authenticity and/or integrity

The main buildings of the Kazan Observatory and the Engelhardt Observatory are authentic and retain their original form. The scientific community has sufficient document evidence on the design, origins and condition of monuments at different periods of time. Preserved authentic instruments used by the scientists in the 19th and 20th centuries who made observations and breakthroughs, still have their uniqueness and relevance and nowadays serve as an educational and training tool for undergraduate students, masters, graduate students, and are used for fundamental research by eminent scientists. The architectural monuments had undergone conservation works, maintenance, repair works. The building of the Engelhardt Observatory holds a museum of the history of the Kazan astronomical school. Attributes inherent in the complex of astronomical observatories, including form and design, building materials and substances, use and function, location and environment, etc. are ensured by the observance of the necessary requirements for conservation, maintenance. According to the degree of development of the building of the city astronomical observatory and the Engelhardt Observatory are among the historical urban landscape and are included in the ensemble of Kazan University and the naturally developing landscape with forest surroundings.

The integrity of the complex of astronomical observatories and the safety of attributes marking their outstanding universal value are ensured by the established boundaries of objects and their buffer zone. The boundaries of urban and suburban astronomical observatories cover a sufficient area. The boundaries of the buffer zone cover all important viewpoints and prevent the possibility of multi-story construction, which could disrupt the visual perception of objects. Thanks to the protective measures taken in the 20th–early 21st centuries the museum and the planetarium aimed at presentation and popularization of astronomy as an important scientific discipline and the world breakthroughs made in these buildings. The condition of their conservation and astronomical instruments is good. The authenticity and integrity of the observatories are ensured by republican and federal legislation. By decree of the President of the Russian Federation Kazan Federal University has been listed as a site of special significance for the peoples of the Russian Federation.

Comparison with other similar properties

There are about 500 observatories in the world, most of which are located in the northern hemisphere of the Earth. The most famous are astronomical observatories to study stars, galaxies, planets and other celestial objects. There are also meteorological observatories for weather observation; geophysical observatories for study of atmospheric phenomena, in particular – polar lights; seismic stations for registration of vibrations caused in the Earth by earthquakes and volcanoes; observatories for observation of cosmic rays and neutrinos. Many observatories are equipped not only with serial instruments for registration of natural phenomena, but also with unique instruments providing the highest sensitivity and accuracy under specific observation conditions.

The staff of the former observatories were priests and ministers of religion. The Chaldeans built ziggurats or temple observatories; the Chinese had them as branch departments of the mathematical tribunal. Since ancient times there were observatories in Beijing, Luoyang and other cities; the Egyptian pyramids, judging by the orientation of their sides with respect to cardinal directions, were also built to produce famous astronomical observations; traces of the existence of the former observatories were found in India, Persia, Peru and Mexico. In addition to large government observatories, private ones were also built in ancient times, such as the well-known Eudox Observatory in Cnidus. The main tools of the ancient observatories were: a gnomon for systematic observation of the midday heights of the sun, a disk dial and clepsydras to measure time; some people observed the moon and its phases, planets, moments of sunrise and sunset of celestial bodies, their passage through the meridian, solar and lunar eclipses without the help of tools.

The first observatory in the modern sense was the famous museum in Alexandria, organized by Ptolemy II Philadelphus. A number of astronomers such as Aristill, Timoharis, Hipparchus, Aristarchus, Eratosfen, Heminus, Ptolemy and others raised this institution to an unprecedented level. Here, for the first time, instruments with divided circles were used. Aristarchus installed a copper circle on the portico of the museum in the equator plane and with its help observed directly the time of the Sun's passage through the equinox points. Hipparchus invented astrolabe with two mutually perpendicular circles and dioptrae for observations.

After destruction of  Alexandria museum with all its collections and instruments - observatories started to be organized again by Arabs and nations conquered by them; there appeared observatories in Baghdad, Cairo, Maragheh (Nasir al-Din al-Tusi), Samarkand (Ulugh-Beg’s) and so on. Arab scientist Geber set up an observatory in Seville, the oldest in Europe. From the beginning of the XVI century it was in Europe that the construction of observatories began, first private, and then governmental: Regiomontanus set up an observatory in Nuremberg (1471), Wilhelm IV, the Landgrave of Hesse, in Kassel (1561) and others. The famous Tycho Brahe used his entire fortune of over 100,000 Krone for the buildings and tools for his observatory on the island of Hven, near Copenhagen. He was the first in Europe to use metal instruments with circles separated after 1'. The private observatory of Hevelius was also very famous.

Since the early 2000s, the experts of the World Heritage Center have drawn attention to the lack of astronomical heritage sites on the World Heritage List. In this regard, as part of the global strategy to develop the UNESCO World Heritage List, a pilot project "Astronomy and World Heritage Thematic Initiative" was launched in 2003 in order to identify and inscribe sites related to astronomy on the World Heritage List. The project has several objectives: to establish a link between science and culture for the identification and recognition of objects related to astronomical observations; to identify the variety of objects on this subject that are scattered in different geographical regions; and to link scientific and traditional local knowledge in the study of astronomical heritage.

This thematic initiative offers State Parties to the UNESCO Convention "Concerning the Protection of the World Cultural and Natural Heritage" the opportunity to assess and recognize the importance of a new type of cultural heritage for the enrichment of human history and display of cultural diversity. The sky is an integral part of the general environment perceived by humanity, and the inclusion of the interpretation of the sky as a theme in the world heritage is a natural logical step. Such a step is necessary to recognize and protect cultural values and cultural landscapes that define and decipher the relationship between mankind and the sky. Close and continuous interaction between astronomical knowledge and its role in human culture is an important element of outstanding universal value.

At the moment the UNESCO World Heritage List includes 9 astronomical sites:

  1. Pulkovo Observatory (as part of the UNESCO-protected site "Historic Centre of Saint Petersburg and Related Groups of Monuments"(Russia, 1990, ref. 540 bis);
  2. Maritime Greenwich (London, Great Britain, 1997, ref. 795);
  3. Stonehenge, Avebury and Associated Sites (Great Britain, 1986, ref.373 bis);
  4. Jantar Mantar in Jaipur (India, 2010, ref. 1338 );
  5. Dengfeng Observatory as a part of "Historic Monuments of Dengfeng in “The Centre of Heaven and Earth" nomination. (China, 2010, Ref.1305rev);
  6. Ulugh-Beg's Observatory as a part of the nomination "Samarkand – Сrossroad of cultures". (Uzbekistan, 2001, Ref: 603rev);
  7. "Struve Geodetic Arc" (Belarus, Estonia, Finland, Latvia, Lithuania, Norway, Republic of Moldova, Russian Federation, Sweden, Ukraine, 2005, ref. 1178);
  8. Jodrell Bank Observatory (United Kingdom, 2019, Ref.1594);
  9. Cultural landscape of Risco Caido and the sacred mountains of Gran Canaria (Spain, 2019, Ref.1578 ).

Out of the four sites inscribed on the UNESCO World Heritage List under the Astronomy and World Heritage Initiative (Dengfeng, Jantar Mantar, Jodrell Bank, Risco Caido and the Sacred Mountains of Gran Canaria Cultural Landscape), three are observatories and one is an archaeological complex associated with ancient traditional astronomical beliefs. Interestingly, as part of the astronomical initiative, the list does not yet include any observatories with an optical telescope (the most familiar for our apprehension). The city observatory of Kazan University, and later the suburban observatory n.a. V.P. Engelhardt (EAO) were two of the leading centers of optical astronomical research in the XIX - XX centuries, not only in the Russian Empire, the USSR, but also throughout Eastern Europe and Eurasia, and their inscription will help to fill this gap.

It should also be noted that two objects (the Chinese observatory Dengfeng and the place of ancient astronomical observations on the island of Gran Canaria) were included as parts of a wider nomination - historical and cultural complex and cultural landscape. A detailed analysis of other UNESCO World Heritage sites shows that there are other astronomical heritage sites in this list, which were included as a part of fairly extensive structural or territorial nominations. There are about ten of them, they are in this list under various categories, and the first of them was included in the list back in 1988 - the observatory, located on the territory of the ancient Mayan city of Chichen-Itza (Mexico). The circular building of the Caracol Observatory for the observation of celestial phenomena with a spiral staircase (by which it was named "El Caracol" - "snail" in Spanish) was inscribed on the UNESCO World Heritage List in the nomination "Pre-Hispanic City of Chichen-Itza". The largest discovered astronomical complex of the ancient population of the Yucatan Peninsula was built before 904 AD, during the highest heyday of the Mayan civilization. Originally, the observatory was a two-storey tower, placed on a square platform. Small windows in the cylindrical tower were aimed at the most important positions of the Sun and the Moon, corresponding to the periods of solstice and equinox. Astronomers believe that the observatory in Chichen-Itza was built to monitor the activity of Venus, the main planet of the Mesoamerican pantheon. The Mayans believed that Venus was a war planet and sister of the God of wisdom Kukulkan. Scientists have found marks in El Caracol that indicate that the Mayans accurately calculated the cycle of Venus, which consists of 584 days. In total, the inhabitants of Chichen-Itza knew the nature of 20 out of 29 astronomical phenomena important for the region, and all discoveries were made by the priests-astronomers of El Caracol.

Pulkovo Observatory was inscribed on the UNESCO list in 1990. The then USSR, soon after joining the World Convention, nominated the first site from our country. Pulkovo Observatory was included as a part of "Historic Center of St. Petersburg and Related Groups of Monuments" nomination - extensive in terms of the number of objects and a significant area covered. This nomination included the main monuments of the historical center of St. Petersburg, royal palaces in its suburbs, ancient fortresses, including the old part of Kronstadt and its forts, suburban manor houses and memorial complexes. The observatory was also among the historical monuments in the nomination. The first director of Pulkovo Observatory, opened in 1839, was the outstanding astronomer Vasily Yakovlevich Struve (Friedrich Georg Wilhelm von Struve), thanks to whose efforts the Observatory received excellent equipment for that time (including the world's largest telescope refractor of the time). Since 1844, the Pulkovo Meridian was used as a reference point for longitude in the Russian Empire. During the Great Patriotic War, the observatory was destroyed, but all the equipment and scientific library were preserved. In 1954 the observatory was restored and reopened, mainly in the former architectural forms.

In 1997 another famous observatory was inscribed on the World Heritage List - Greenwich Royal Observatory in Great Britain. It was also included as a part in the complex Maritime Greenwich nomination, which combined the buildings of the Old Royal Naval College, the park area with the Queen’s House and the observatory complex.

The observatory was organized in 1675 by King Charles II and was designed to clarify the coordinates and ensure navigation. The project of the observatory, as well as the magnificent hospital building, was developed by Christopher Wren, one of the most prominent English architects. It was Greenwich Observatory that became the point of reference for longitude in the world after the 1884 international agreement, and it is Greenwich that we measure mean solar time world-wide. At the moment, the observatory has a museum of astronomical and navigational instruments, planetarium and study rooms. On the territory of the observatory there is a metal tape, fixing the zero meridian, and in the night sky the meridian is marked by a laser beam.

The next observatory to be inscribed on the World Heritage List was the Cheomseongdae Observatory (Republic of Korea), which was included as a part of the complex spatial site "Gyeongju Historic Areas" in 2000. Gyeongju District is home to many remarkable monuments of Korean Buddhist art, including pagodas, ruins of temples and palaces. This district is one of the largest open-air historical museums, and includes four groups of monuments. The preserved buildings are mainly from the period of VII-X centuries. Here is the observatory tower, located as well as the ruins of Wolseong palace site (Crescent Palace) on the territory of The Wolseong Belt, which dates back to the VII century. This is one of the oldest observatories and scientific buildings on Earth. The tower is composed of 362 granite stones, embodying 362 days of the lunar year (according to another version, the number of stones is 366), the area of the upper platform of the tower is equal to the half of its base area.

In 2001 another ancient observatory – Ulugh-beg’s Observatory (Uzbekistan), was also nominated and inscribed on the UNESCO Heritage List as a part of the complex of cultural heritage sites "Samarkand - Crossroad of cultures". This nomination comprised main attractions of Samarkand - three madrasas on Registan Square, the cathedral mosque Bibi-Khanum, Shakhi-Zinda compound, Gur-Emir ensemble and the above-mentioned Ulugh-beg’s Observatory, built in the suburbs of ancient Samarkand. Ulugh-beg was the grandson of Tamerlan, who ruled in Samarkand from 1409 to 1449. It was there that the city became a world center of science, where madrasas were opened, historians, mathematicians and astronomers worked. The Observatory was built in 1424-1428, its main tool was a grandiose diopter - a sextant, with which astronomers measured the height of the celestial bodies as they passed through the celestial meridian. The underground part of the device is well preserved nowadays. The catalogue of the starry sky was made in the observatory, which included more than thousand stars and which was not surpassed in accuracy of observations for two following centuries.

In 2005 a serial nomination "Struve Geodetic Arc" - a chain of triangulation points, stretching for 2820 km from Hammerfest on the northern tip of Norway to the Black Sea through the modern territory of Norway, Sweden, Finland, Russia, Estonia, Latvia, Lithuania, Belarus, Ukraine and Moldova was inscribed on the UNESCO World Heritage List. These reference points were laid in 1816-1855 by Friedrich Georg Wilhelm von Struve, the astronomer who made the first reliable measurement of the large arc segment of the earth's meridian. Measurements of the Struve Arc allowed to accurately determine the size and shape of our planet, which was an important step in the development of Earth sciences and topographic mapping. It was an exceptional example of international cooperation in the scientific field.

The arc consisted of 258 geodetic polygons with 265 main triangulation points. The World Heritage Site includes 34 such points (the most well-preserved to date), which are marked on the ground in a variety of ways: in some cases there are hollows carved in the rocks, pyramids of stones, iron crosses or specially installed obelisks.

Tartu Observatory in Estonia (as a former triangulation point "Dorpat") became a World Heritage site as a part of Struve's Arc. The observatory was founded in 1810 in the city of Dorpat in the Livonian province of the Russian Empire at the local university (Dorpat - the German name of the city, in 1893 it was renamed into Yuriev, now - Tartu). When Friedrich Georg Wilhelm von Struve began building the Arc, the observatory was its first measuring point.

The historic building of the observatory was built on the Toome Hill - the highest point of the city - according to the project of architect Johann Wilhelm Krause. Now the building of the historical observatory houses a museum, and it is part of the public scientific education center, on its basis there is a club of amateur astronomy.

In addition to the listed observatories, we can also name a group of historical monuments included in the UNESCO World Heritage List, which is logically attributed to the astronomical heritage. These are archaeological sites, the construction of which could presumably have been undertaken for astronomical observations. The most famous of them, for example, are the megalithic monuments of Stonehenge (UK) and Lines and Geoglyphs of Nasca and Palpa (Peru).

The World Heritage Site "Stonehenge, Avebury and Associated Sites" was inscribed in 1986. Stonehenge and Avebury are located in English Wiltshire County and are one of the most famous groups of megaliths in the world. The sanctuaries consist of large ring-shaped stone pillars of menhirs, placed in a certain order. Their construction dates back to the XXX century BC. These buildings were, presumably, treated as a sanctuary, as burial places, there is also a version that they were a kind of Stone Age observatory in which the position of the stones and the gaps between them allowed to record the summer solstice and other phenomena.

Another World Heritage site, "Lines and Geoglyphs of Nasca and Palpa", was inscribed on the UNESCO List in 1994. The Geoglyphs (geometric figures or drawings applied to the surface of the earth) of Nasca and Pampas de Jumana are located in the middle of a desert plain in the coastal part of Peru, about 400 km south of Lima, and cover an area of about 450 square kilometers. Up to date about 30 drawings, 700 geometrical figures and 13 thousand different lines and stripes have been revealed. These lines and drawings, carved out on the surface between 500 BC and 500 AD, are one of the archeological riddles. Since the drawings are several hundred meters in size, they are very difficult to recognize from the ground and can only be seen from a bird's-eye view. Their exact purpose has not yet been determined, but one hypothesis suggests that they may have performed ritual astronomical functions.

The number of archaeological objects supposedly associated with astronomical tasks is significant. Hypotheses of their astronomical purpose are based on the spatial location of archaeological sites, their orientation on the four winds, on the solstice points, on bright stars, or on cosmogonist ideas of ancient peoples. However, in most cases, such hypotheses have not yet received firm scientific confirmation.

Another group of historical monuments related to astronomical heritage can be singled out among the cultural heritage objects - architectural structures, which were once used for astronomical observations and research. The Giralda, the bell tower of Seville Cathedral, is one of the typical examples of this group of monuments. The Cathedral along with the adjoining Alcázar Palace complex and the General Archive of the Indies in Seville were registered by UNESCO in 1987. The cathedral was built in 1401-1519 on the site of the destroyed Almohad mosque. However, the minaret of the mosque was preserved and used as a bell tower of the Seville Cathedral. The minaret itself was built in 1184-1198 on the prototype of the famous minarets in Marrakech (Morocco). During Arab rule, the flat roof of the minaret allowed its use as an observatory, and it was one of the famous observatories in the Arab world.

Another World Heritage Site to include observatory is the Tower of London - an imposing fortress with many layers of history, which has become one of the symbols of Britain's royalty. Under Charles II the royal observatory was situated in the White Tower of the fortress.

The historical place of astronomical observations is also a part of the World Heritage site "The Loire Valley between Sully-sur-Loire and Chalonnes". It is the most extensive object of France, inscribed on this list (its length is 280 km). Among the architectural masterpieces here are several historic cities and ancient castles. In one of them - the Castle of Chenonceau - there was a small observatory, an ancient room for astronomical observations has been preserved and is located on the top floor of the castle tower.

Astronomical observations were also conducted in the building of the Kunstkamera in St. Petersburg, which was built in 1718-1734. This architectural masterpiece is part of the category "Historical Center of St. Petersburg and Related Groups of Monuments". The observatory was located in the tower of the building, it also housed the famous Gottorp Globe, once the world's largest globe-planetarium with a diameter of 3.1 m, created in the middle of the XVII century and brought to St. Petersburg in 1717 as a diplomatic gift to Peter I. In 1747, the tower was destroyed in a fire and restored in the middle of XX century.

The famous astronomer Galileo Galilei conducted his observations and experiments in Pisa, Florence and in Rome. Some memorial sites associated with his observations are now UNESCO World Heritage sites. The historical observatory was also located in the Vatican, which is also inscribed on the UNESCO list in the nomination "Historic Centre of Rome, the Properties of the Holy See in that City Enjoying Extraterritorial Rights and San Paolo Fuori le Mura".

Thus, we can say that today the UNESCO list of astronomical heritage is represented by the following objects:

- buildings and structures of historical observatories (both ancient observatories and observatories with optical telescopes and even radio telescopes);

- places with evidence of traditional astronomical perceptions of local people (the cultural landscape of Risco Caido and the sacred mountains of Gran Canaria);

- historical sites that once housed astronomical observations or observatories itself situated (e.g., the Seville Cathedral Bell Tower, the Kunstkamera building, etc.);

- archaeological heritage sites believed to have been used for astronomical observations (e.g., Stonehenge and the geoglyphs of the Nasca desert).

The first two groups are represented by nine historical observatories and one cultural landscape (Table). Probably one can also add a serial World Heritage site "Struve Geodetic Arc", which is more of a geographical and geodetic heritage site, but also closely related to the theory and history of astronomical observations.


Characteristics of the astronomical heritage included in the UNESCO World Heritage List (as of early 2020)

Name of the site and date of its inscription on the list


Date of foundation

Characteristics of the object



Cheomseongdae Observatory (in the category of Historical Territories of Gyeongju), 2000.   

Republic of Korea (South Korea),

VII century

Observatory of preoptic period of astronomical observations


Caracol Observatory (in the nomination "Pre-Hispanic City of Chichen-Itza"), 1988


X century

Observatory of preoptic period of astronomical observations.


Dengfeng Observatory (in the nomination "Historic Monuments of Dengfeng in “The Centre of Heaven and Earth"), 2010.        


XIII century

Observatory of preoptic period of astronomical observations


Ulugh-beg’s Observatory (in the nomination "Samarkand - Crossroad of cultures"), 2001


XV century

Observatory of preoptic period of astronomical observations


Greenwich Royal Observatory (in the nomination "Maritime Greenwich"), 1997

Great Britain

XVII century

Observatory of the optical period of astronomical observations.


Jantar Mantar Observatory (independent nomination), 2010


XVIII century

Observatory of preoptic period of astronomical observations


Tartu Observatory (as a part of the nomination "Struve Geodetic Arc", 2005


XIX century

Observatory of the optical period of astronomical observations


Pulkovo Observatory (as a part of "Historic Centre of Saint Petersburg and Related Groups of Monuments" nomination, 1990

Russia Observatory of

XIX century

Observatory of the optical period of astronomical observations


Jodrell Bank Observatory (independent nomination), 2019.

Great Britain,

XX century

Observatory of the period of radio astronomical observations

Territories associated with astronomical heritage


Cultural landscape of Risco Caido and the sacred mountains of Gran Canaria (independent nomination), 2019


III-XV centuries

Cultural Landscape, containing evidence of traditional astronomical beliefs of ancient local inhabitants

Based on this table, we can see that the list includes only one cultural and landscape area with evidence of traditional astronomical knowledge of local people. In addition, most of the observatories are on the World Heritage List as part of complex nominations rather than as an independent site. Only two observatories - the Jantar Mantar Observatory with preoptic celestial instruments and the Jodrell Bank Observatory with radio telescopes - are independently nominated cultural heritage sites. Not a single optical observatory and its scientific, cultural and spatial evolution has been independently nominated.

Kazan University Observatories, being an outstanding example of optical observatories of XIX-XX centuries in their integrity, excellent state of conservation and authenticity of their attributes, have made an invaluable contribution to the development of science in Eastern Europe, Eurasia and the world in general. Discovering unknown corners of the universe, continuing the traditions of Kazan astronomical school and embodying scientific and cultural continuity for two centuries up to date, both sites will take a well-deserved place in the UNESCO World Heritage List. In addition, the evolution of the astronomical observatories of Kazan University, in particular the observatory named after V.P. Engelhardt with the creation of an astropark and a planetarium on its territory in order to popularize science for young generations and to exhibit the main astronomical objects in an accessible model form to demonstrate traditional astronomical concepts of the peoples of Russia, testifies to the uniqueness of the objects of this nomination.

Replenishment of the World Heritage List on the basis of the astronomical heritage on these missing aspects - nomination of observatories with historical traditions of optical observations and nomination of cultural landscapes related to traditional astronomical representations of different peoples of the world, first of all observatories of Kazan University, will enrich the knowledge of the world community about the astronomical heritage, in general, and its authentic optical observatories, which have made a huge contribution to the research and study of the moon and planets of our Galaxy.

Architecture of astronomical observatories

As for the observatories of both preoptical and optical period of observation, it should be noted that in the XVII and XVIII centuries, the buildings of the observatories themselves were few. This included the aforementioned observatory of Tycho Brahe Uraniborg (1576), the first building in Europe specially built for astronomical observations, observatories in Paris (1667) and Greenwich (1675). Otherwise, the already existing towers of fortifications, churches and castles were used for astronomical observations. As an example, we can mention the Rundetårn, within the university complex of the University of Copenhagen (1642), and Astronomical observatory in the tower of the Jesuit College Clementinum complex of baroque buildings in Prague (1725), “La Specola” in Bologna (1725), “La Specola” Osservatorio Astronomico di Padova (1761) and the Royal Academy in St. Petersburg, where the Gottorp Globe  was installed (1725). The other possibilty were platforms like Hevelius' Observatory in Danzig / Gdańsk (1649), the observatory on a bastion of the castle in Nuremberg (1677). Observatories were also located on the roof of the buildings. Thus, on the roof of a stone medieval house in Central Uppsala in 1741 Andres Celsius founded an astronomical observatory, the oldest in Sweden.

The next step was around 1800 with observatories in Neo-Classicistic style, which used the shape of the Greek Cross, mostly built by famous architects. The architecture of observatories in XIX century was characterized by a three-dome facade. Kazan City Observatory was among the first in Europe with such an innovative design, setting the trend in the architecture of astronomical observatories as independent structures for the development of science and technology. In 1834 Helsinki Observatory was built by Carl Ludwig Engel (1778–1840), in 1837 - “old” Kazan University Observatory (Mikhail Petrovich Korinfsky (1788–1851) and in 1839 – Pulkovo Observatory, St. Petersburg (Alexander Brullov (1798–1877).

Later on, several foreign neoclassical observatories were built, such as the National Observatory in Athens (Theophil Hansen, 1846), the new Observatory in Berlin (Karl Friedrich Schinkel, 1836), the Observatory in Bonn (Karl Friedrich Schinkel, 1844) and the Observatory in Quito, Ecuador (1873), the oldest in South America, astrophysical Observatory Potsdam-Telegrafenberg (1879), University Observatory Potsdam-Babelsberg (1913) and "German Museum" in Munich (1925), an institution for the popularization of science and technology, especially astronomy, with two domes for the refractor and reflector and a middle dome for the world's first planetarium (originally in the oval hall on the 3rd floor).


Topics of research in the 19th century were positional astronomy with meridian circles for compiling star catalogues, celestial mechanics and timekeeping, especially for navigation, and surveying. Johann Georg Repsold (1770-1830) invented in 1803 the first modern meridian circle (since 1818 preserved in Göttingen Observatory). The workshop Repsold, founded in Hamburg in 1799, developed as “Adolf & Georg Repsold” (1830 to 1867) and as “A. Repsold & Sons” (1867 to 1919) and delivered astronomical instruments to observatories all over the world.

In the Engelhardt Astronomical Observatory (1901) in Kazan there is a meridian circle, made by Repsold in 1845. This circle was ordered for Kazan Astronomical Observatory to replace the Vienna Meridian Circle, which was badly damaged during a terrible fire on August 24, 1842 in Kazan, and could not be restored. Repsold's Meridian Circle was brought to Kazan Observatory in 1847 by M.V.Lyapunov. In 1895 an impersonal micrometer with a micrometer in declination was purchased to it.

In 1900, all parts of the instrument were sent to Repsold for remake, except for the circles, because they were of excellent quality. To modernize the circle, Repsold produced new axle machining, drilled a cube, improved precision in inclination, produced a new level for the horizontal axis. Also, 4 new microscopes - micrometers - were made to avoid repositioning the microscopes when repositioning the tool, and a new supporting installation microscope was installed. In the workshops, counterbalance circuits were made, three wire meshes were adapted to the lens to reduce the brightness of stars, and electrical lighting was also adapted.

After the remake, the meridian circle was brought to the Engelhardt Observatory in 1902 and was finally installed in the autumn of 1903 in a pavilion of corrugated galvanized iron. The walls of the hall were double with an air layer of 0.4 meters. Special fans were adapted for air circulation. The roof of the pavilion was sliding. On the south and north sides of the hall observation hatches of 1.2 meters width were located. The height of the room was 6 meters. The foundation for the supporting pillars of the instrument was a concrete slab, located at a depth of 3 meters under the soil. A brick parallelepiped with a height of 2.5 meters was erected on top of it. Inside it there were the poles, which rised above the floor of the hall by 2 meters and were isolated from the rest of the foundation and the floor with glycerine. The distance between them was 1.1 meters. The tool itself has been kept in a wooden sliding house in order to protect against the heat. On a separate pole, there is a mercury horizon.

The diameter of the meridian circle lens is 135 mm and the focal length is 195 cm. There are four eyepieces with magnification 120, 150, 190 and 250 times. Symmetrically on both sides of the tube there are circles - the main circle is two minutes and the additional circle is ten minutes. The scale with divisions is applied to the silver strip. The accuracy of application of divisions is of high quality. On both sides of the pipe there are wooden handles in the form of circles to control the device. Fixing screws are located in the ocular part of the telescope. For ease of observation there is a special moving on rails and an upward chair, in which the observer can take a comfortable position.

Around the meridian circle there are two mires, each of them is 130 meters away from the center of the mercury horizon. The southern mire had to be raised to a height of 5.5 meters by filling a special burial mound. Pavilion of the southern mire built in the Pseudo-Byzantine style also houses a tomb. The northern mire is located on the other side of the meridian hall near the observatory lake. The mires themselves are iron planks with a side square of 35 cm. They are screwed on copper plates measuring 12 x 22 cm and 0.5 cm thick. The hole in this board is 1.5 mm, lit by an electric light bulb. It gives the mire artificial sprocket in 2 seconds in diameter, which is easy to observe at a distance of 147.6 meters from the instrument. Both mires are precisely located at coaltitude of 90 degrees from the instrument and the line of the mires deviates from the meridian by about 0.2 seconds. To observe the mires in the ocular part of the tube there is an additional movable lens.

To study the horizontal bending of the pipe of the meridian circle small horizontal collimators with 11 cm lenses and 165 cm focal length were installed in front of the hatches at a distance of 1.5 meters from the pavilion on special poles.

In 1920, the meridian circle was removed and the wooden lining of the poles was replaced by cement lining. In 1923 the meridian circle was thoroughly cleaned and installed. In 1924 the mercury horizon was debugged and the telescope lighting was put in order.

The coordinates of stars on the celestial sphere were determined on the meridian circle of the EAO. Measurement of the positions of stars in the sky is the basis and foundation of all astronomy. Catalogues, published as a result of these observations, are necessary in determining the exact time, geographical coordinates on the Earth's surface, in the preparation of geographical maps in navigation, topography and geodesy, the study of the rotation of the Earth, the structure of the Galaxy, etc.

Systematic observations on the meridian circle at the Engelhardt Observatory were started in 1903 by M.A. Grachev with the aim of studying the instrument. In 1909 he began observations of a large number of stars between 5.5 and 6.5 of magnitude. Within 10 years about 10 000 observations were made. Later, I.A. Dyukov joined the observations and started to work on the international program. Then the Astronomical Observatory named after V.P. Engelhardt participated in all collective observation works, such as the compilation of the "Catalogue of geodesic stars", included in the programs to determine the geographical coordinates of triangulation points. It was the first major collective work of the USSR astronomers. Observations and their processing were carried out by I.A.Dyukov and L.D.Agafonova before all other participants of this collective work and the results were published in 1943 in the journals of Kazan University Astronomical Observatory.

The EAO took an active part in the international work on compilation of the Fundamental Catalogue of Weak Stars (FCWC). Three stages of work were carried out: differential and absolute determination of declensions of the FCWC and observation of declensions of the general catalog. Later on, both the differential and absolute catalogues of the EAO were used in the preparation of the "Preliminary Fundamental Catalogue of Weak Stars". A.I.Nefedyeva became the main observer on the meridian circle. She did a lot of work to study the anomalous refraction due to the inclination of air layers in the Engelhardt Observatory. The observations on the meridian circle were used. The coordinates of large planets were also measured on this instrument and the declensions of Mercury, Venus, Mars, Jupiter and Saturn were determined. All the results have been published in press.

During these extensive observation programs, the meridian circle was modernized: instead of visual microscopes for counting the limb, cameras of the original design, which work smoothly at all air temperatures, were installed. This modernization increased the efficiency of the observer by several times and made the observation process much easier. A semi-automatic electronic computer was designed to measure limb dashes. About 100,000 definitions of the declensions of stars and planets were made on the meridian circle. Conducted research of the tool showed that the instrumental errors for 120 years of work practically did not change, except for the tube bending, changing slightly after the telescope maintenance check-up.

The Meridian Circle of Repsold in Engelhardt Observatory is fully authentic, still a working instrument and of great historical and cultural value. By the example of this instrument you can trace the history of evolution of an authentic instrument - a masterpiece of human genius of the master Repsold, as well as evolution of optical astronomy for two centuries.

 In addition to the meridian circle, the EAO also has other instruments unique in their historical value - an azimuth mark, a remarkable heliometer (Repsold, 1874, moved to EAO in an extra dome in 1908), a 68-mm-transit instrument (Carl Bamberg of Berlin), a universal instrument (Fennel of Vienna), chronometers (Knoblich of Hamburg) and astronomical pendulum clocks (Tiede of Berlin), and a chronograph (Fuess of Berlin). Grubb refractor, owned by V. P. Engelhardt, in the 80-s of the XIX century was one of the best in Germany, and by the end of 90-s, when Vasily Pavlovich decided to retire, was a desirable acquisition for any observatory of the world. Many observatories of Germany and Russia claimed  these instruments, but V.P. Engelhardt bequeathed them to Kazan University.

Meridian circles could also be found in the observatories in La Plata / Argentina, Rio de Janeiro / Brazil, Naval Observatory in Washington D.C., as well as in Lisbon / Portugal, Bruxelles / Belgium, Strasbourg / France, Konkoly (Hungary) or Pulkovo / Russia. In Hamburg Observatory there is a 19-cm-meridian-circle (f=2,3-m), made by A. Repsold & Sons (Hamburg 1909).

 Unique authentic tools of the XIX century of Kazan University observatories, perfectly preserved and still used both in the learning process and in observations, which have been tested for centuries and have proven their effectiveness and relevance today, can be compared in their parameters, importance, contribution to science, authenticity, integrity and state of conservation with the instruments of astronomical observatories in Hamburg, Konkoly and La Plata. Let us analyze several positions.

Typical for the classical astronomy were large refractors. In Kazan, you can find the 31cm = 12''-Engelhardt-equatorial, made by Howard Grubb of Dublin (1879); it was the second largest refractor in the German Empire (Dresden) after Strassburg Observatory, with clock drive, an illuminated position micrometer (Repsold of Hamburg). The optics of the 136-mm-seeker of the equatorial, was made by Reinfelder & Hertel of Munich, the mounting was made by G. Heyde of Dresden. In addition a 6" comet seeker, Merz of Munich, was used.

In La Plata Observatory [Forte 2009, p. 201] you can find a 21.6-cm-equatorial refracting telescope (f=3.1m), made by Paul Gautier of Paris (1881), a 21-cm-meridian circle, 2 zenith telescopes, an astrograph, and a larger 43-cm-refracting telescope (f=9.6-m), all made by Gautier until 1890 (optics made by Henry Brothers). Then since 1906 La Plata Observatory acquired German instruments: a large Repsold meridian circle (19-cm-objective, made by Zeiss), a Zeiss 20-cm-comet-seeker, two Repsold transit instruments (objectives made by Steinheil of Munich) and Wanschaff zenith telescopes (A. Repsold & Son of Hamburg). In addition there existed around 1900 seismographical instruments, a meteorological tower and precision pendulum clocks for time keeping (for navigation).

In Hamburg Observatory in Bergedorf there is an Equatorial Telescope, made by A. Repsold & Sons (1867) for the "old" observatory, transferred to the new one. In addition there is large 60-cm-Refractor (9-m focal length) in a large 13-m-dome (mechanics made by A. Repsold & Sons, Hamburg, 1911, optics made by Steinheil of Munich (visual lens, 1914, photographic lens, 1925). Very impressive is also one of the first lifting platforms (height 4,50-m) in the world, made by Zeiss of Jena, 1909.

Several authentic instruments have been preserved in Konkoly observatory. A Newton Cassegrain type telescope of 60 cm, with a guiding telescope of 30 cm. This instrument was mostly used for the photography of globular clusters (M3, M15, M56), to identify and study any variable stars contained therein. Observations made with this telescope were also used in the exploration of minor planets and comets, to determine their position and to calculate their orbits. The leader of this project was György Kulin, who, discovered twenty minor planets and two new comets between 1938 and 1948.

An astrograph of 16 cm (f=1:14) with a guiding telescope of 19 cm. This instrument was used to study the d Cephei and RR Lyrae type stars, which was from its inception one of the most important work done by the observatory. On the basis of forty thousand photographs László Detre and his wife Julia Balázs have managed to obtain a clarification of some peculiarities of the light-curves of the RR Lyrae type stars. During their investigations they maintained a close contact with the authorities working on similar problems, such as P Th Osterhoff, Otto Struwe, Harlow Shapley, Wilhelm Becker and others.

A Heyde type refractor of 20 cm with two smaller photographic cameras, salvaged from Ógyalla. This instrument was mainly used in the study of eclipsing binaries

In the Astronomical Observatory named after V.P. Engelhardt there is a gravimetric laboratory with authentic equipment, which had been in operation since the beginning of the 20th century and is still used by scientists from all over Russia. There are also gravimetric laboratories at the Jozefoslaw Observatory (1957, Poland), the Gravimetric Observatory in Poltava (1926, Ukraine), the Gravimetric Observatory of Strasbourg as part of the School and the Earth Sciences Observatory (France, 1997). The Royal Observatory of Belgium (1826) is considered to be founded earlier than AOE, but gravimetric studies there began only in the 90-s of the XX century. Thus, the gravimetric laboratory in the EAO is one of the first such places in the world and today makes a huge contribution to the development of science.

The significance of the instruments used in observations, research and great discoveries of the XIX-XX centuries cannot be overestimated. Without tools, there would be no facts known to science today, and in a historical context they serve as a concrete reference point for the development of scientific theory. We are living in an era of science-intensive technology; it has created an environment that could never exist without tools, and this fact should be the focus of attention. Undoubtedly, the demonstration of tools in a historical setting in astronomical observatory museums is essential to public understanding of these truths.

In 2018, the IAU prepared a list of "outstanding astronomical heritage", those astronomical observatories that are fundamental in the history of astronomy. The list of outstanding astronomical heritage included: Kazan: Old University Observatory (1837) – IAU code 135, EAO (1901) – IAU code 136; La Plata, IAU code 839; Hamburg Observatory Millerntor, IAU code 516, Observatory Hamburg-Bergedorf, IAU code 029). Some important observatories cannot be included in the World Heritage list because the important condition for UNESCO, an architectural monument (with the non-moveable instruments), is not fulfilled. If you look at observatories as an historian of astronomy, you would evaluate not mainly the building, but also the collections which illustrate the history and importance of an observatory like instrument collections, a large photographic plate collection, a rich archive of historical material and maps, library, and especially the significance in the history of astronomy (looking at famous astronomers due to their results and publications). All these attributes are an evidence of outstanding universal value and are available in Astronomical Observatories of Kazan University.

In the second half of XIX century there were significant changes in architecture, more precisely infrastructure, of astronomical observatories - the idea of an “Astronomy Park” with many different buildings and domes came up. Astronomy parks were founded in Nice Observatory (1879), La Plata (1883/86) [7 ha area with 18 buildings, including domes], EAO (1899/1901) [21 ha], Hamburg-Bergedorf (1906/12) [7 ha area], Bruxelles (1883/90) and in the USA (US Naval Observatory Washington D.C. 1887).

The idea of an astronomy park observatory was realised in Hamburg and EAO with a strict separation of observatory domes on one side and the main building with the library and administration, the office buildings and the workshop on the other side. At the same time, the Astrological Park of AOE is the largest among its historical "brothers".

The complex includes about 40 objects of scientific, educational and cultural-entertaining character. The astropark territory is divided into zones: transit, thematic and intellectual. A planetarium was built on the territory of the Astronomical Observatory for educational, educational and cultural events in 2013. Equipped with the latest equipment, it blends in seamlessly with the observatory complex. Since 2016 the planetarium has been named after twice Hero of the Soviet Union, pilot-cosmonaut A.A. Leonov.

In the western part of the Planetarium building is located the Observatory Tower, which includes a complex of telescopes: 20 - inch wide angle astrograph reflector for observation of deep space (Astrograph Widefield Reflector) with a planepolar corrector, 8 - inch Fluorit (CaF2) triple apochromatic reflector with a diaphragm number f/7. 5 to study the solar system and two solar telescopes of 110 and 130 mm. (130mm S-FPL53, triple apochromatic Refractor with diaphragm number f/6.5 and 110 mm Fluorite (Flourit(CaF2) triple apochromatic Refractor with diaphragm number f/5.7). The observatory is used for teaching astrophotography students, sky surveys for scientific research and popularization of astronomy. In the central part of the building there is a hall, where interactive excursions and various events are held. And in the east wing is the "Star Hall" for 83 seats with a dome diameter of 15 m and a dome slope of 10 degrees. With the help of modern equipment (MEGASTAR optical-mechanical projector manufactured in Japan and DomeSky digital system with Epson laser projectors) spherical films are demonstrated, lectures, presentations, etc. are held.

The planetarium carries out educational and awareness raising activities for all segments of the population. The Planetarium conducts educational classes in various sections of astronomy, basics of cosmonautics and other topics of natural science for schoolchildren of 1-11 grades and students of all institutes and faculties of Kazan Federal University and other educational institutions of the region. There are programs in English. For schoolchildren of 10th and 11th grades there are cycles of school astronomy courses, which consist of a lecture by a teacher - an astronomer, demonstrations of the starry sky and watching a full-dome film on the lecture subject. On the basis of the Planetarium there are courses on improvement of professional skill and retraining of teachers of astronomy, classes of astronomical clubs "Lira", "Space scouts", etc., scientific seminars and conferences are held. Every year over 30000 children and adults attend the events held by the Planetarium.

In addition, a multi-disciplinary Space Astrometry Center has been established on the basis of the Astronomy park, which is capable of ensuring effective application of the results of space activities and training of high quality specialists in this field. The Center is tasked with the development of a metrological test site for testing satellite equipment, creation of a ground support service for Russian and international space programs (GLONASS, Luna-Glob, Phobos-Grunt, etc.).

The development of observatories, especially in Hamburg and Kazan University, have a common program of development in the implementation of relevant scientific tasks at each stage of their historical development, which has led to the history of their territorial location of the research centers, first in the city and afterwards – in the countryside.

Also worth mentioning is the Konkoly Observatory in Hungary, founded in 1899, which has a history of localization of research centers similar to that of Kazan and Hamburg. As well as the V.P. Engelhardt Astronomical Observatory, it "grew" from a private observatory when Miklós Konkoly-Thege handed over his collection of instruments from a well-equipped observatory founded in 1871 in Ógyalla (present-day Slovakia) to the Hungarian state.

Without stopping at private observations in his observatory, the astronomer was determined to make a breakthrough and establish a school of Astronomy in a country, where not a single observatory was in existence (the last one was blown to bits 22 years earlier, on the order of the Austrian military authorities).

In 1874 he built an observatory of two domes in the park of his palace at Ógyalla. In one of the domes he erected a 10.5 inch Browning reflector, in the other a 6 inch Merz refractor which was augmented with a Zöllner type spectroscope. The photographs, compiled in the Ógyallan Catalogue of Spectra by Radó Kövesligethy, were produced using this instrument. A Rheinfelder heliograph was used for the observation of the sun. The observatory housed an extensive collection of spectrometers. Within a few years Konkoly had to realise, that he could not provide the funds necessary to keep his institute up to date out of his own pocket. For this reason he started his struggle to have his Observatory at Ógyalla taken over by the state. In 1898 the Astronomische Gesellschaft showed its solidarity with its Hungarian colleagues by holding their Annual Meeting in Budapest. This event may have contributed to the Hungarian state's decision finally to accept Konkoly's offer on the 16 May, 1899.

The Ógyalla Astrophysical Observatory of the Konkoly Foundation expanded rapidly after the take-over. Astronomical photometry and photography became its main area of interest. 

The Observatory was occupied by the troops of the new Czech state in 1919. However, many instruments were salvaged and together with the two telescopes, salvaged from Ógyalla, a Cassegrain-Newton type telescope of 60 cm served as a basis for the new observatory. It consisted of three new domes and an office building in the Buda-hills. The Slovak Central Observatory continues to operate in a building in Ógyalla (Hurbanov). A large part of the instruments has also been preserved.

After World War I, Ógyalla became part of the Czechoslovak Republic. The government moved scientific equipment to Budapest before the closure of the newly formed border, and in 1921 it allocated a new site on the hills of Budapest west of Budapest for the construction of a new astronomical observatory. The new building, known as the Svábhegy Observatory named after the nearby hill, was completed by 1924, and by 1928 a 6-inch refractor and a 60-centimeter telescope Heyde were installed in the new domes. Scientific work at the observatory focused on variations in the luster of pulsating stars, double-star orbits and search for asteroids. Measurements were made with photoplates and wedge photometers.

The history of the Ógyalla (Gurbanovo, Slovakia) and Svábhegy (Hungary) observatories represents the development of research centers, the formation of which intersects with the scientific problems resolved also in Kazan and Hamburg observatories and reflects the stages of development of astronomical scientific thought.

In the second half of XIX century astronomy underwent a revolution. In the context of “classical astronomy”, only the direction of star light was studied. In the 1860s quantity and quality of radiation were studied for the first time. This was the beginning of modern “astrophysics”. Instead of combining astronomy with mathematics with compiling large star catalogues and the calculation of orbits of the planets and comets, around 1860 astronomers began to investigate the properties of celestial bodies with physical and chemical methods.

This new field of astrophysics caused, and was caused by, new instrumentation: spectrographs and object lens prisms, instruments for astrophotography (portrait lenses, astrographs), photometers for measuring the brightness of stars (starting with the visual Zöllner photometer in 1860, later photographic and photoelectric photometry), solar physics instruments (since 1868, photo-heliograph, spectroheliograph, later coronograph) and laboratory equipment for analyzing the photographic plates and spectra (cf. blink comparator, spectrum comparator, measuring devices for getting the stellar magnitudes like iris diaphragm photometer, etc.).

In the last quarter of the 19th century only a few centres of astrophysics existed in the world. Besides the Astrophysical Observatory Potsdam, where astrophysics was born, one should mention Göttingen, Heidelberg, Bonn, Bamberg and Hamburg in Germany, then observatories in Hungary, Italy (Collegio Romano Rome in the 1870s), England (Greenwich Astrophysical Department 1873), France (Meudon Solar Observatory 1876), Russia (Pulkovo Astrophysical Department 1882) and South America (La Plata 1886), also in the United States (Harvard, Cambridge, Mass. 1870s; Lick, Mt. Hamilton 1888, Yerkes, Wisconsin 1897) and India (Kodaikanal Solar Observatory 1899, since 1972, field station of the Indian Institute of Astrophysics in Bangalore).

Concerning astrophysics in Kazan, an ocular spectroscope according to Vogel and a universal spectroscope, made by Merz, Munich, with a four prism system à vision directe were used. An early visual photometer (a wedge photometer) was also in use. In Kazan existed a 120-mm-astrograph, made by G. Heyde, Dresden, with objective prism. Another astrograph was acquired in 1914 [Nefediev 2019, p. 38]. Especially in the time of Dmitry Yakovlevich Martynov (1906-1989), in 1938, the Head of the Department of Astrophysics of Kazan University, the founder of the Russian school in this field of research, the interest in astrophysics increased. In the field of photometry the “EAO Kazan Variable Star Conference” (1932) was organized. In addition Kazan astronomers made Solar Eclipse Expeditions with astrograph, 11-m-coronagraph (1914, 1936 and 1941).

Hamburg Observatory was also active in Solar Eclipse Expeditions (Samarkand 1907, Mexico 1923, Atlantic 1925, Jokkmokk, Finland, 1927, Philippines 1929) [Wolfschmidt 2014].

The most important and influential invention in Hamburg Observatory was the Schmidt telescope. Bernhard Schmidt (1879–1935) opened his Optical Workshop first in Mittweida near Chemnitz (1901 to 1927), then in Hamburger Observatory (1927 to 1935); there he constructed this remarkable wide angle photographic instrument with a spherical mirror and a glass correction plate, which allows the imaging of a large field of the sky without any distortions - avoiding spherical aberration, coma and astigmatism. The first Schmidt Telescope (1930) had 36-cm aperture, 63-cm focal length and focal ratio 1:1.75.

The 80-cm-Hamburg-Schmidt-Telescope, made by Zeiss of Jena, 1954 (1.20-m, f=2.40-m) was brought to Calar Alto, Southern Spain in 1976, because of the better weather conditions. Now one can find Schmidt telescopes all over the world like the “Big Schmidt” (1.26-m, 1.83-m, f=3.07-m), Mount Palomar (1938-1948), 1-m-ESO-Schmidt, La Silla, Chile (1973) and Tautenburg near Jena (1.34-m, 2.00-m, f=4.00-m), built by VEB Zeiss Jena (1960).

In this context Maksutov telescope became a phenomenon. In 1936, Dmitri Dmitriyevich Maksutov (1896–1964), a member - correspondent of the USSR Academy of Sciences, started with his work which led to the invention of a system which uses a thick (spherical) negative meniscus lens for correcting the spherical aberration combined with a spherical main mirror. The meniscus telescope design was published in 1944.

Maksutov telescope also became an important breakthrough in the evolution of technology for astronomical observatories. A photographic mirror telescope of the Maksutov system - AST-452 - was installed at the Engelhardt Astronomical Observatory in 1963. The optical scheme of the telescope is a classic variant of the optical meniscus system developed by the designer of the astronomical technique D.D.Maksutov. Though he created and offered a large number of systems, it is meniscus telescopes that are connected with his name. Such telescopes are compact, have the closed tube, high quality of the image. The telescope was manufactured in Kazan at the Optical and Mechanical Plant in Derbyshki by special order.

The telescope has a meniscus, a polarizing lens, and three objective prisms. All of them are made of vitreous glass. This allows spectral and photometric observations in close ultraviolet to 3400 angstrom. The diameters of the light hole of the meniscus and the main mirror of the telescope are 350 mm and 490 mm respectively. The telescope can work in two optical schemes.

For survey cameras, the Schmidt and Maksutov systems were also combined, used e.g. in Kazan (38/52-cm-Schmidt-Maksutov-telescope, 1938); resulting a telescope with the extreme aperture ratio and a wide field of about 50°.

All observatories have also acquired or built modern instruments since 1945 (e.g. radio astronomy), opened expedition stations or branch observatories and made the turn to satellite astronomy (e.g. in Kazan observations of artificial Earth satellites in 1957), astrometry with Hipparcos and especially X-ray astronomy (Hamburg and Kazan).

These studies have been especially active in Kazan in recent years and have reached a new level due to the extensive international cooperation of scientists led by R. Syunyaev and the satellites launched by Roscosmos.

Considering ten criteria for evaluation of outstanding universal value (OUV) and comparing Observatories of Kazan University with Hungarian and Hamburg observatories and a number of other world observatories, it is necessary to note such features for a number of OUV criteria as:

(i) It represents a masterpiece of human creative genius.

Being a ‘collective instrument’ the Observatories represent a masterpiece of human creative genius demonstrating revolutionary achievements in science, engineering and technology. The Kazan Observatory was founded, began to function successfully and made a huge contribution to the development of astrophysics, geodesy and astronomy only due to the tenacity and faith in the idea of exclusivity of astronomical science at Kazan University by Kazan astronomers. These are: Joseph Johann von Littrow; the founder of the oldest Department of Astronomy in Russia, I.M. Simonov, the mastermind behind the establishment of the Observatory, astronomer, member of the round-the-world expedition of Lazarev and Bellingshausen, which discovered Antarctics; mathematician N.I. Lobachevsky; astronomers M. Kovalsky, M. Lyapunov, D. Dubyago and many others. According to this criterion, out of independent nominations the World Heritage List also includes the Jodrell Bank Observatory with the Lovell telescope. But this observatory applies to radio astronomy, while in the observatories of Kazan University we talk about the classic optical observatory, the birth and active development of astrophysics. According to i criteria, the List also includes Greenwich, Ulugh-beg, Stonehenge and Pulkovo observatories, but they are all parts of larger nominations.

(ii) exhibit an important interchange of human values, over a span of time or within a cultural area of the world, on developments in architecture or technology, monumental arts, town-planning or landscape design.

This is shown in the revolutionary change of the research field: “From classical astronomy to modern astrophysics around 1900”. This causes a change in the architecture and in the instrumentation (and observation technology) – from meridian circle, refractor, heliometer to new instruments like astrograph, reflecting telescope, Schmidt telescope and several astrophysical instruments. In addition this also changes the observatory layout, from one building with domes to an ensemble of buildings in an astronomy park. In this context for Hamburg Observatory, also striking inventions like the Schmidt-Telescope and the breakthrough of the reflecting telescopes with the Zeiss company should be mentioned and for Kazan – Maksutov system telescope and the combination of Schmidt and Maksutov systems for survey cameras.

(iv) be an outstanding example of a type of building, architectural or technological ensemble or landscape which illustrates (a) significant stage(s) in human history.

The three observatory buildings have an impressive architecture (Neo-Classical or Neo-Baroque style), they are well preserved and restored. Integrity and authenticity (OUV) is fulfilled in respect to architecture, instrumentation and observatory layout. The observatories are cultural monuments with high scientific, technological and historical significance. With the instrumentation the observatories show the whole development of astronomical instrumentation and observation technology. Many instruments in Kazan and some other observatories were made by German makers; showing the close cooperations between the observatories (letters e.g. in the Repsold archive).

(vi) be directly or tangibly associated with events or living traditions, with ideas, or with beliefs, with artistic and literary works of outstanding universal significance (the Committee considers that this criterion should preferably be used in conjunction with other criteria).

The observatories are characterized by important inventions and results of research of universal value. This can be seen in the publications, in the existence of famous astronomers – like Repsold, Walter Baade, Bernhard Schmidt and Otto Heckmann, first General Director of ESO from 1962 to 1969, for Hamburg; Joseph Johann von Littrow and Nikolai Lobachevsky, Dmitriy Dubiago for Kazan; Antal Taas, László Detre, Károly Lassovszky, Imre Izsák for Konkoly, Hungary. Another evidence of direct connection with events of world importance in astronomy were numerous examples of  international cooperations of these observatories with world-leading centres of astronomy (star catalogues, solar eclipse expeditions, Venus transit expeditions, ESO, Hipparcos and nowadays many satellite projects).

Finally all three observatories are open to the public with a lot of activities and events like star gazing evenings, lectures, guided tours, museums and exhibitions (Schmidt Museum Hamburg and Long Night of Museums, Museo de Astronomía y Geofísica La Plata, 1997, Kazan of Museums, Kazan observatory), Heritage day – Day of the open Monument, Day of the open House, Astronomy Workshop (special astronomical education programmes in Hamburg for school children), special courses for university students, and a Planetarium (La Plata and Kazan).

Kazan University Observatories can be considered as a model of continuity from classical positional astronomy, to which Kazan scientists have made a huge contribution, to the origin of astrophysics due to its location (an astronomical park in the outskirts of the city - EAO), and also due to the choice of astrophysical instruments, astrographs, thanks to the introduction of modern reflectors, well suited for astrophysics, telescopes of Maxutov, Schmidt. In addition, well-preserved unique authentic XIX century instruments, typical for classical astronomy, such as the meridian circle and refractor, and others. Many of these and other instruments of classical astronomy can also be found in La Plata and Hamburg.

The change in the direction of research "from classical astronomy to modern astrophysics" can be clearly seen in the observatories of Kazan University, Hamburg and La Plata around 1900. The changes in instrumentation, impressive architecture (integrity and authenticity, well preserved and restored), and the idea of an ensemble of buildings in an astronomical park are all important cultural heritage associated with the leading observatories of the time. This corresponds to the main categories according to which the "outstanding universal value" of the observatories is assessed: historical and cultural, scientific and aesthetic.

Comparative analysis has shown that the astronomical observatories of Kazan University have exceptional characteristics, which are not yet represented in other sites on the UNESCO World Heritage List. Such key characteristics include the following:

  • Kazan University Observatories are a bright representative of the general historical evolution of the phenomenon of observatory’s development, both urban and suburban, in a new environment. They contribute to the essence of history and culture, the development of science, because they are a modification in the new historical, cultural and natural conditions.
  • Kazan University Observatories is an outstanding evidence of the development of classical optical astronomical paradigm, most clearly manifested in the activities of Kazan University scientists, the change of scientific codes and identities, the gradual formation and transition from positional astronomy to astrophysics, the culmination of a certain period of its development in time and territory.
  • Kazan University observatories are the brightest illustration of an independent optical observatory, a category insufficiently represented in the World Heritage List. Most of the observatories are represented within larger nominations, only Jodrell Bank and Jantar-Mantar are presented as independent sites. However, they are radio astronomical and preoptic astronomical observatories respectively. Observatories for the optical period of observations in the UNESCO List include the Royal Greenwich Observatory, Tartu Observatory and Pulkovo Observatory, which are parts of larger nominations. Thus, astronomical observatories of Kazan University will be the first optical period observatories to be included as independent sites.
  • Preservation of features and attributes indicates that the observatories of Kazan University are a prime example of authentic objects of the middle of XIX - XX centuries, with their genesis, historical stratification and continuity in the development of science and technology.
  • Architecture, good preservation, integrity, unique authentic tools of the XIX-XX centuries allow to highlight the main attributes of Outstanding Universal Value and features associated with the inclusion of the object of science and technology in urban life.
  • The territory of the astrological park, the planetarium at the astronomical observatory named after V.P. Engelhardt, continuing classes for students in the city observatory with authentic tools allow to popularize science among the younger generation, to be imbued with the spirit of the great discoveries of outstanding scientists of Kazan University, made with the help of this toolkit, to demonstrate and carry on the continuity in the development of science in the XIX-XXI centuries.
  • Kazan University observatories are an outstanding example of specific urbanization, architecture and synthesis between cultures of European, Russian and elements of Eastern (Tatar), the symbiosis between man and nature, architecture, culture and nature.
  • Astronomical observatories of Kazan University and their territory are the repository of traces of continuous scientific, historical and cultural, architectural, spiritual evolution, which accumulated layers of different epochs - optical, astrophysical, radio astronomical and ultramodern periods of astronomical observations and included the features of Russian history and culture as a manifestation of outstanding historical and cultural continuity.
  • This context includes significant intangible values associated with important historical events and persons, breakthrough scientific discoveries of the world level, publications, symbolic characteristics, valuable traditions and images.

Astronomical observatories of Kazan University represent an exceptional and outstanding example and make their unique contribution to the world cultural and scientific and technical heritage. Comparative analysis has shown that the observatories of Kazan University have important attributes that reflect the changes associated with the development of astronomical science in the XIX - XX centuries, the architecture of astronomical heritage in Eastern and Central Europe, as well as in the whole of Eurasia and the world in this historical period. Kazan University's observatories and their history reflect important aspects that are important for understanding of their role in world science and in this geocultural region, which have not yet been recognized for optical period observatories as an independent site in the UNESCO World Heritage List.