meter telescope. Where are the largest telescopes on Earth located? Large South African Telescope SALT

I was immediately reminded in the comments that it was necessary to write about the BTA-6 as well. I fulfill my wishes :-)

For many years, the world's largest telescope BTA (Large Azimuth Telescope) belonged to our country, and it was designed and built entirely using domestic technologies, demonstrating the country's leadership in the field of creating optical instruments. In the early 60s, Soviet scientists received a “special task” from the government - to create a telescope larger than that of the Americans (Hale telescope - 5 m.). It was considered that a meter more would be enough, since the Americans generally considered it pointless to create solid mirrors larger than 5 meters due to deformation under their own weight.

What is the history of the creation of this unique scientific object?

Now we find out...

By the way, the first photo is very, be sure to look at it too.

Photo 3.

M. V. Keldysh, L. A. Artsimovich, I. M. Kopylov and others at the BTA construction site. 1966

The history of the Large Azimuth Telescope (BTA, Karachay-Cherkessia) began on March 25, 1960, when, at the suggestion of the USSR Academy of Sciences and the State Committee for Defense Technology, the Council of Ministers of the USSR adopted a resolution on the creation of a complex with a reflecting telescope having a main mirror with a diameter of 6 meters.

Its purpose is “the study of the structure, physical nature and evolution of extragalactic objects, a detailed study physical characteristics And chemical composition non-stationary and magnetic stars. The State Optical and Mechanical Plant named after A.I. OGPU (GOMZ), on the basis of which LOMO was soon formed, and the chief designer was Bagrat Konstantinovich Ioannisiani. BTA was the latest astronomical technique for its time, containing many truly revolutionary solutions. Since then, all large telescopes in the world have been mounted according to the brilliantly justified alt-azimuth scheme, for the first time in world practice used by our scientists in the BTA. The highest-class specialists worked on its creation, which ensured high quality giant device. For more than 30 years, BTA has been carrying out its stellar watch. This telescope is capable of distinguishing astronomical objects of the 27th magnitude. Imagine the earth is flat; and then, if someone in Japan would light a cigarette, with a telescope it could be clearly seen.

Photo 4.

Cleaning the bottom of the pit. February 1966

After analyzing all the data, the site for the BTA telescope was a place at an altitude of 2100 meters near Mount Pastukhov, not far from the village of Zelenchukskaya, which is located in Karachay-Cherkessia - Nizhny Arkhyz.

According to the project, the azimuthal type of telescope mount was chosen. The total outer diameter of the mirror was 6.05 meters with a thickness of 65 cm, uniform over the entire area.

The assembly of the telescope structure was carried out in the LOMO room. Especially for this, a building with a height of over 50 meters was built. Cranes with a lifting capacity of 150 and 30 tons were installed inside the hull. Before starting the assembly, a special foundation was made. The assembly itself began in January 1966 and lasted more than a year and a half, until September 1967.

Photo 5.

Construction of the foundations of the telescope and tower. April 1966

By the time the mirror blank with a diameter of 6 m was manufactured, the accumulated experience in processing large-sized optical blanks was not great. For processing a casting with a 6-meter diameter, when it was necessary to remove about 25 tons of glass from a workpiece, the existing experience turned out to be unsuitable, both because of low labor productivity and because of the real danger of the workpiece failure. Therefore, when processing a workpiece with a diameter of 6 m, it was decided to use a diamond tool.

Many of the telescope components are unique for their time, such as the main spectrograph of the telescope, which has a diameter of 2 meters, the guiding system, which includes a telescope-guide and a complex photo and television system, as well as a specialized computer for controlling the operation of the system.

Photo 6.

Summer 1968 Delivery of telescope parts

BTA is a world-class telescope. The large light-gathering capacity of the telescope makes it possible to study the structure, physical nature and evolution of extragalactic objects, a detailed study of the physical characteristics and chemical composition of peculiar, non-stationary and magnetic stars, the study of star formation and the evolution of stars, the study of the surfaces and chemical composition of planetary atmospheres, trajectory measurements of artificial celestial bodies at large distances from the Earth and much more.

With its help, numerous unique studies of outer space were carried out: the most distant galaxies ever observed from Earth were studied, the mass of the local volume of the Universe was estimated, and many other mysteries of space were solved. Petersburg scientist Dmitry Vyshelovich, using the BTA, was looking for an answer to the question of whether the fundamental constants drift in the Universe. Based on his observations, he major discoveries. Astronomers from all over the world are lining up to make observations with the famous Russian telescope. Thanks to the BTA, domestic telescope builders and scientists have accumulated vast experience, which made it possible to open the way to new technologies for studying the Universe.

Photo 7.

Installation of metal structures of the dome. 1968

The resolution of the telescope is 2000 times greater than the resolution of the human eye, and its radius of "vision" is 1.5 times greater than that of the largest US telescope at that time in Mount Palomar (8-9 billion light years versus 5-6, respectively ). It is no coincidence that BTA is called the “Eye of the Planet”. Its dimensions are amazing: height - 42 meters, weight - 850 tons. Thanks to the special design of hydraulic supports, the telescope seems to “float” on the thinnest oil cushion 0.1 mm thick, and a person is able to turn it around its axis without the use of equipment and additional tools.

By the Decree of the Government of March 25, 1960, the Lytkarinsky Optical Glass Plant was approved as the lead contractor for the development of a technological process for casting glass blanks of a mirror with a diameter of 6 m and for the manufacture of mirror blanks. Two new production buildings were built specifically for this project. It was necessary to cast a glass blank weighing 70 tons, anneal it and carry out complex processing of all surfaces with the manufacture of 60 landing blind holes on the back side, a central hole, etc. Three years after the Government Decree was issued, a pilot production workshop was created. The task of the workshop included the installation and debugging of equipment, the development of an industrial technical process and the manufacture of a mirror blank.

Photo 8.

A complex of search works carried out by LZOS specialists to create optimal processing modes made it possible to develop and implement a technology for manufacturing an industrial blank of the main mirror. The processing of the workpiece was carried out for almost a year and a half. In 1963, the Kolomna Heavy Machine Tool Plant created a special carousel machine KU-158 for mirror processing. In parallel, a lot of research work was carried out on the technology and control of this unique mirror. In June 1974, the mirror was ready for certification, which was successfully completed. In June 1974, the critical stage of transporting the mirror to the observatory began. On December 30, 1975, the act of the State Interdepartmental Commission for the acceptance into operation of the Large Azimuthal Telescope was approved.

Photo 9.

1989 Assembly of the 1-meter Zeiss-1000 telescope

Photo 10.

Transportation of the upper part of the BTA pipe. August 1970

Today, there are new, more efficient astronomical systems with larger, including segmented, mirrors. But in terms of its parameters, our telescope is still considered one of the best in the world, so it is still in high demand among domestic and foreign scientists. Over the past years, it has undergone repeated modernization, primarily the management system has been improved. Today, observations can be made using a fiber optic connection directly from the astronomy town located in the valley.

Photo 11.

The Soviet optical industry of those times was not designed to solve such problems, therefore, to create a 6-meter mirror, a factory was specially built in Lytkarino near Moscow on the basis of a small workshop for the manufacture of mirror reflectors.

The blank for such a mirror weighs 70 tons, the first few were “screwed up” due to haste, since they had to cool for a very long time in order not to crack. The “successful” billet cooled down for 2 years and 19 days. Then, during its grinding, 15,000 carats of diamond tools were produced and almost 30 tons of glass were “erased”. A fully finished mirror began to weigh 42 tons.

The delivery of the mirror to the Caucasus is worth a special mention .. First, a dummy of the same size and weight was sent to the destination, some adjustments were made to the route - 2 new river ports were built, 4 new bridges were built and 6 existing ones were strengthened and expanded, several hundred kilometers were laid new roads with perfect coverage.

The mechanical parts of the telescope were created at the Leningrad Optical and Mechanical Plant. The total mass of the telescope was 850 tons.

Photo 12.

But despite all efforts, the American Hale BTA-6 telescope failed to "surpass" in quality (that is, in resolution). Partly due to defects in the main mirror (the first pancake is still lumpy), partly due to the worst climatic conditions at its location.

Photo 13.

The installation in 1978 of a new, already third mirror, significantly improved the situation, but weather remained the same. In addition, the too high sensitivity of the whole mirror to minor temperature fluctuations complicates the work. "Does not see" - this is of course loudly said, until 1993 BTA-6 remained the world's largest telescope, and it is the largest in Eurasia to this day. With the new mirror, it was possible to achieve a resolution almost like that of Hale, and the “penetrating power”, that is, the ability to see faint objects, is even greater for the BTA-6 (after all, the diameter is a whole meter larger).

Photo 14.

Photo 15.

Photo 16.

Photo 17.

Photo 18.

Over the 30-year period of the telescope's operation, its mirror was recoated several times, which led to significant damage to the surface layer, its corrosion, and, as a result, up to 70% of the mirror's reflectivity was lost. And yet, the BTA has been and remains a unique tool for astronomers, both Russian and foreign. But in order to maintain its performance and increase efficiency, it became necessary to reconstruct and update the main mirror. At present, the technology of mirror shaping and unloading, which is mastered by the specialists of JSC LZOS, makes it possible to improve its optical characteristics threefold, including the angular resolution.

Photo 19.


Today, the technological process of shaping the surfaces of astronomical optical parts at the Lytkarino Optical Glass Plant has been brought to a new level, the achieved quality of surface shape deviations from the theoretical one has increased by an order of magnitude due to automation and modernization of production and computer control. Both the mechanical base and the technology for lightening and unloading mirrors using modern computer equipment have been significantly improved. Machines for milling, grinding and polishing a 6-meter mirror are also modernized in accordance with modern requirements. Optics controls have also been significantly improved.

The main mirror was delivered to the Lytkarino Optical Glass Plant. The milling phase has now been completed. The top layer about 8 mm thick was removed from the working surface. The mirror was transported into a thermally stabilized case and installed on an automated machine for grinding and polishing the working surface. According to the technical director - the chief engineer of the enterprise S.P. Belousov, this will be the most difficult and important stage of mirror processing - it is necessary to obtain a surface shape with much smaller deviations from the ideal paraboloid than was achieved in the seventies. After that, the telescope's mirror with resolution and penetrating power improved by an order of magnitude will be able to serve Russian and world science for at least 30 more years.

Photo 20.

Among the specialists who participated in the manufacture of the mirror are the mechanic Zhikharev A.G., the optometrist Kaverin M.S., the locksmith Panov V.G., the milling machine Pisarenko N.I. – they are still working, passing on the rich experience of large-sized optical instrumentation to young people. Quite recently, the optician Bochmanov Yu.K., the milling machine Egorov E.V. have retired. (he re-milled the mirror last year and this year).

No one else in Russia can do such a job. In the world, besides LZOS, there are only two companies that manufacture large-sized mirrors. These are the Steward Observatory Optical Laboratory (Arizona, USA) and the SAGEM-REOSC company (France) (8 m in diameter), but even there the mirror control towers are shorter than required, since the radius of the BTA mirror is 48 meters.

Thanks to telescopes, scientists have made amazing discoveries: they discovered a huge number of planets beyond solar system learned about the existence of black holes at the centers of galaxies. But the Universe is so huge that this is only a grain of knowledge. Here are ten current and future giants of ground-based telescopes that give scientists the opportunity to study the past of the universe and learn new facts. Perhaps with the help of one of them it will even be possible to detect the Ninth planet.

BigSouth Africantelescope (SALT)

This 9.2-meter telescope is the largest ground-based optical instrument in the southern hemisphere. It has been operating since 2005 and focuses on spectroscopic surveys (registers spectra various kinds radiation). The instrument can view about 70% of the sky observed in Sutherland, South Africa.

Keck I and II telescopes

The twin 10-meter telescopes at the Keck Observatory are the second largest optical instruments on Earth. They are located near the top of Mauna Kea in Hawaii. Keck I started operating in 1993. A few years later, in 1996, the Keck II. In 2004, the first adaptive optics system with a laser guide star was deployed at the combined telescopes. It creates an artificial star spot as a guide to correct atmospheric distortion when viewing the sky.

Great Telescope of the Canaries (GTC)

The 10.4-meter telescope is located on the peak of the extinct volcano Muchachos on the Canary island of Palma. It is known as an optical instrument with the largest mirror in the world. It consists of 36 hexagonal segments. GTC has several support tools. For example, the CanariCam camera, which is capable of examining the mid-range infrared light emitted by stars and planets. CanariCam also has unique ability block bright starlight and make faint planets more visible in photographs.

Arecibo Observatory Radio Telescope

It is one of the world's most recognizable ground-based telescopes. It has been operating since 1963 and is a huge 30-meter radio reflecting dish near the city of Arecibo in Puerto Rico. The huge reflector makes the telescope particularly sensitive. It is able to detect a weak radio source (distant quasars and galaxies that emit radio waves) in just a few minutes of observation.

ALMA Radio Telescope Complex

One of the largest ground-based astronomical instruments is presented in the form of 66 12-meter radio antennas. The complex is located at an altitude of 5000 meters in the Atacama Desert in Chile. The first scientific studies were carried out in 2011. ALMA radio telescopes have one important purpose. With their help, astronomers want to study the processes that took place during the first hundreds of millions of years after the Big Bang.

Up to this point, we have been talking about already existing telescopes. But now many new ones are being built. Very soon they will begin to function and significantly expand the possibilities of science.

LSST

This is a wide-angle reflecting telescope that will take pictures of a certain area of ​​the sky every few nights. It will be located in Chile, on top of Mount Sero Pachon. While the project is only in development. The full operation of the telescope is planned for 2022. Nevertheless, high hopes are already pinned on him. Astronomers expect LSST to give them the best view of those far away from the Sun celestial bodies. Scientists also suggest that this telescope will be able to notice space rocks that could theoretically collide with the Earth in the future.

Giant Magellan Telescope

The telescope, which is expected to be completed by 2022, will be located at the Las Campanas Observatory in Chile. Scientists believe that the telescope will have four times the ability to collect light compared to existing on this moment optical devices. With it, astronomers will be able to discover exoplanets (planets outside the solar system) and study the properties of dark matter.

Thirty meter telescope

The 30-meter telescope will be located in Hawaii, next to the Keck Observatory. It is planned that it will begin to operate in 2025-2030. The aperture of the device is capable of providing a resolution 12 times higher than that of the Hubble Space Telescope.

SKA radio telescope

SKA antennas will be deployed in South Africa and Australia. Now the project is still under construction. But the first observations are planned for 2020. The sensitivity of the SKA will be 50 times that of any radio telescope ever built. With its help, astronomers will be able to study signals from a younger universe - the time when the formation of the first stars and galaxies took place.

Extremely Large Telescope (ELT)

The telescope will be located on the Cerro Amazone mountain in Chile. It is planned that it will start working only in 2025. However, he has already become famous for the huge mirror, which will consist of 798 hexagonal segments with a diameter of 1.4 meters each. The technical characteristics of the ELT will allow it to study the composition of the atmospheres of extrasolar planets.

B.M. Shustov, Doctor of Physical and Mathematical Sciences,
Institute of Astronomy RAS

Mankind has gathered the bulk of knowledge about the Universe using optical instruments - telescopes. Already the first telescope, invented by Galileo in 1610, made it possible to make great astronomical discoveries. Over the next centuries, astronomical technology was continuously improved and the modern level of optical astronomy is determined by the data obtained using instruments hundreds of times larger than the first telescopes.

The trend towards ever larger instruments has become particularly clear in recent decades. Telescopes with a mirror with a diameter of 8 - 10 m are becoming common in observational practice. Projects of 30-m and even 100-m telescopes are estimated as quite feasible already in 10 - 20 years.

Why are they being built

The need to build such telescopes is determined by tasks that require the ultimate sensitivity of instruments for detecting radiation from the faintest space objects. These tasks include:

• the origin of the universe;
• mechanisms of formation and evolution of stars, galaxies and planetary systems;
• physical properties of matter in extreme astrophysical conditions;
• astrophysical aspects of the origin and existence of life in the Universe.

To get the maximum information about an astronomical object, a modern telescope must have large area of ​​collecting optics and high efficiency of radiation receivers. Besides, Observation interference should be kept to a minimum..

At present, the efficiency of receivers in the optical range, understood as the fraction of detected photons from the total number of photons that arrived at the sensitive surface, is approaching the theoretical limit (100%), and further improvements are associated with increasing the format of receivers, speeding up signal processing, etc.

Observation interference is a very serious problem. Beyond interference natural character(for example, cloudiness, dust formations in the atmosphere) the threat to the existence of optical astronomy as an observational science is the growing illumination from settlements, industrial centers, communications, technogenic pollution of the atmosphere. Modern observatories are built, of course, in places with a favorable astroclimate. Such places on the globe very few, no more than a dozen. Unfortunately, there are no places with a very good astroclimate on the territory of Russia.

The only promising direction in the development of highly efficient astronomical technology is to increase the size of the collecting surfaces of instruments.

The largest telescopes: the experience of creation and use

In the last decade, more than a dozen projects of large telescopes have been implemented or are in the process of being developed and created in the world. Some projects provide for the construction of several telescopes at once with a mirror no less than 8 m in size. The cost of the instrument is determined primarily by the size of the optics. Centuries of hands-on experience in telescope construction have led to easy way a comparative estimate of the cost of a telescope S with a mirror of diameter D (let me remind you that all instruments with a primary mirror diameter greater than 1 m are reflecting telescopes). For telescopes with a solid primary mirror, as a rule, S is proportional to D 3 . Analyzing the table, you can see that this classic ratio for the largest instruments is violated. Such telescopes are cheaper and for them S is proportional to D a , where a does not exceed 2.

It is the stunning reduction in cost that makes it possible to consider projects of supergiant telescopes with a mirror diameter of tens and even hundreds of meters not as fantasies, but as quite real projects in the near future. We will talk about some of the most cost-effective projects. One of them, SALT, is being commissioned in 2005, the construction of giant telescopes of 30-meter class ELT and 100-meter - OWL has not yet begun, but they may appear in 10 - 20 years.

Large South African Telescope SALT

In the 1970s South Africa's main observatories were merged into the South African Astronomical Observatory. The headquarters is located in Cape Town. The main instruments - four telescopes (1.9-m, 1.0-m, 0.75-m and 0.5-m) - are located 370 km from the city inland, on a hill rising on the dry Karoo plateau ( Karoo).

South African Astronomical Observatory.
South African Large Telescope Tower
shown in section. In front of her are three main
operating telescopes. (1.9m, 1.0m and 0.75m).

In 1948, a 1.9-m telescope was built in South Africa, it was the largest instrument in the southern hemisphere. In the 90s. last century, the scientific community and the government of South Africa decided that South African astronomy could not remain competitive in the 21st century without a modern large telescope. Initially, a 4-m telescope, similar to the ESO NTT (New Technology Telescope) or more modern WIYN, at Kitt Peak Observatory was considered. However, in the end, the concept of a large telescope was chosen - an analogue of the Hobby-Eberly Telescope (HET) installed at the McDonald Observatory (USA). The project was named Large South African Telescope, in original - Southern African Large Telescope (SALT).

The cost of the project for a telescope of this class is very low - only 20 million US dollars. Moreover, the cost of the telescope itself is only half of this amount, the rest is the cost of the tower and infrastructure. Another 10 million dollars, according to modern estimates, will cost the maintenance of the tool for 10 years. Such a low cost is due to both the simplified design and the fact that it is created as an analogue of the already developed one.

SALT (respectively, HET) are radically different from previous projects of large optical (infrared) telescopes. The optical axis of SALT is set at a fixed angle of 35° to the zenith direction, and the telescope is able to rotate in azimuth for a full circle. During the observation session, the instrument remains stationary, and the tracking system, located in its upper part, provides tracking of the object in a 12° section along the altitude circle. Thus, the telescope makes it possible to observe objects in a ring 12° wide in the region of the sky that is 29 - 41° away from the zenith. The angle between the telescope axis and the zenith direction can be changed (no more than once every few years) by studying different regions of the sky.

The diameter of the main mirror is 11 m. However, its maximum area used for imaging or spectroscopy corresponds to a 9.2 m mirror. It consists of 91 hexagonal segments, each with a diameter of 1 m. All segments have spherical surface which drastically reduces the cost of their production. By the way, the blanks of the segments were made at the Lytkarino Optical Glass Plant, the primary processing was carried out there, the final polishing is carried out (at the time of writing the article has not yet been completed) by Kodak. The Gregory corrector, which removes spherical aberration, is effective in the 4? region. Light can be transmitted via optical fibers to spectrographs of various resolutions in thermostatically controlled rooms. It is also possible to set a light instrument in direct focus.

The Hobby-Eberle telescope, and hence the SALT, are essentially designed as spectroscopic instruments for wavelengths in the 0.35-2.0 µm range. SALT is most competitive from a scientific point of view when observing astronomical objects that are evenly distributed across the sky or located in groups of several arc minutes in size. Since the telescope will operate in batch mode ( queue-scheduled), studies of variability during a day or more are especially effective. The range of tasks for such a telescope is very wide: studies of the chemical composition and evolution Milky Way and nearby galaxies, the study of high redshift objects, the evolution of gas in galaxies, the kinematics of gas, stars and planetary nebulae in distant galaxies, the search and study of optical objects identified with X-ray sources. The SALT telescope is located on top of the South African Observatory telescopes, approximately 18 km east of the village of Sutherland ( Sutherland) at an altitude of 1758 m. Its coordinates are 20 ° 49 "East longitude and 32 ° 23" South latitude. The construction of the tower and infrastructure has already been completed. The journey by car from Cape Town takes approximately 4 hours. Sutherland is located far from all the main cities, so it has very clear and dark skies. Statistical studies of the results of preliminary observations, which have been carried out for more than 10 years, show that the proportion of photometric nights exceeds 50%, and spectroscopic nights average 75%. Since this large telescope is primarily optimized for spectroscopy, 75% is a perfectly acceptable figure.

The average atmospheric image quality measured by the Differential Motion Image Monitor (DIMM) was 0.9". This system is placed slightly above 1 m above the ground. Note that the optical image quality of SALT is 0.6". This is sufficient for work on spectroscopy.

ELT and GSMT Extremely Large Telescope Projects

In the USA, Canada and Sweden, several projects of class 30 telescopes are being developed at once - ELT, MAXAT, CELT, etc. There are at least six such projects. In my opinion, the most advanced of them are the American projects ELT and GSMT.

Project ELT (Extremely Large Telescope - Extremely Large Telescope) - a larger copy of the HET telescope (and SALT), will have an entrance pupil diameter of 28 m with a mirror diameter of 35 m. The telescope will achieve a penetrating power an order of magnitude higher than that of modern class 10 telescopes. The total cost of the project is estimated at about 100 million US dollars. It is being developed at the University of Texas (Austin), where experience has already been accumulated in building the HET telescope, the University of Pennsylvania and the McDonald Observatory. This is the most realistic project to implement no later than the middle of the next decade.

GSMT project (Giant Segmented Mirror Telescope - Giant Segmented Mirror Telescope) can be considered to some extent uniting the MAXAT (Maximum Aperture Telescope) and CELT (California Extremely Lerge Telescope) projects. The competitive way of developing and designing such expensive tools is extremely useful and is used in world practice. The final decision on GSMT has not yet been made.

The GSMT telescope is significantly more advanced than the ELT, and its cost will be about 700 million US dollars. This is much higher than that of the ELT due to the introduction aspheric main mirror, and the planned full turn

Stunningly Large OWL Telescope

The most ambitious project of the beginning of the XXI century. is, of course, a project OWL (OverWhelmingly Large Telescope - Stunningly Large Telescope) . The OWL is being designed by the European Southern Observatory as an alt-azimuth telescope with a segmented spherical primary and flat secondary mirrors. To correct spherical aberration, a 4-element corrector with a diameter of about 8 m is introduced. modern projects technologies: active optics (as on NTT, VLT, Subaru, Gemini telescopes), which allows obtaining an image of optimal quality; primary mirror segmentation (as on Keck, HET, GTC, SALT), low cost designs (as on HET and SALT), and multi-stage adaptive optics being developed ( "Earth and Universe", 2004, No. 1).

The Astonishingly Large Telescope (OWL) is being designed by the European Southern Observatory. Its main characteristics are: the diameter of the entrance pupil is 100 m, the area of ​​the collecting surface is over 6000 sq. m, multi-stage adaptive optics system, diffraction image quality for the visible part of the spectrum - in the field 30", for the near infrared - in the field 2"; the field limited by the image quality allowed by the atmosphere (seeing) is 10"; the relative aperture is f / 8; the working spectral range is 0.32-2 microns. The telescope will weigh 12.5 thousand tons.

It should be noted that this telescope will have a huge working field (hundreds of billions of ordinary pixels!). How many powerful receivers can be placed on this telescope!

The concept of gradual commissioning of OWL has been adopted. It is proposed to start using the telescope as early as 3 years before the filling of the primary mirror. The plan is to fill the 60 m aperture by 2012 (if funding opens in 2006). The cost of the project is no more than 1 billion euros (the latest estimate is 905 million euros).

Russian perspectives

About 30 years ago, a 6-m telescope was built and put into operation in the USSR BTA (Large Azimuth Telescope) . For many years it remained the largest in the world and, of course, was the pride domestic science. BTA demonstrated a number of original technical solutions (for example, alt-azimuth installation with computer guidance), which later became the world technical standard. BTA is still a powerful tool (especially for spectroscopic studies), but in early XXI V. it has already found itself only in the second ten largest telescopes in the world. In addition, the gradual degradation of the mirror (now its quality has deteriorated by 30% compared to the original) removes it from the list of effective tools.

With the collapse of the USSR, BTA remained practically the only major instrument available to Russian researchers. All observation bases with moderate-sized telescopes in the Caucasus and Central Asia have significantly lost their significance as regular observatories due to a number of geopolitical and economic reasons. Work has now begun to restore ties and structures, but the historical prospects for this process are vague, and in any case, it will take many years only to partially restore what has been lost.

Of course, the development of the fleet of large telescopes in the world provides an opportunity for Russian observers to work in the so-called guest mode. The choice of such a passive path would invariably mean that Russian astronomy would always play only secondary (dependent) roles, and the lack of a base for domestic technological developments would lead to a deepening lag, and not only in astronomy. The way out is obvious - a radical modernization of BTA, as well as full-fledged participation in international projects.

The cost of large astronomical instruments, as a rule, amounts to tens and even hundreds of millions of dollars. Such projects, with the exception of a few national projects carried out by the richest countries in the world, can only be implemented on the basis of international cooperation.

Opportunities for cooperation in the construction of class 10 telescopes appeared at the end of the last century, but the lack of funding, or rather the state interest in the development of domestic science, led to the fact that they were lost. A few years ago, Russia received an offer to become a partner in the construction of a large astrophysical instrument - the Great Canary Telescope (GTC) and the even more financially attractive SALT project. Unfortunately, these telescopes are being built without the participation of Russia.