Notes from a Pulkovo astronomer about a trip to Chile, at the ESO observatory. In astronomical paradise. Notes from a Pulkovo astronomer on a trip to Chile, at the ESO Observatory Astronomer from Chile

Let's talk about the stars? Not fictional human consciousness and exploited media, and the most real ones - celestial bodies and galactic constellations. So, about heavenly affairs.

Did you know that the Chilean desert is recognized as the best place in the world for stargazing? Chile is an astronomical power. He is in charge of planets, small and large, as well as stellar bodies and the Milky Way.

The secret is that Chile (specifically the Atacama Desert) has crystal clear skies. This is facilitated by a number of important factors: dry air, low clouds, altitude above sea level (more than 2000 meters), distance from large light sources. And a pinch of practical magic. In short, the Chilean desert is literally made for... astronomical observations.

Chile is an astronomical power. He is in charge of planets, small and large, as well as stellar bodies and the Milky Way.

A very large telescope. That's what it's called

According to official data, by 2024, 70% of all astronomical observations in the world will be carried out in Chile. Specifically, in the Atacama Desert. And if you carry out even greater detail - with the help of the most powerful telescopes in the world. The observatories in Chile are famous throughout the world. For example, Paranal, the largest and most advanced astronomical complex on earth, home to the most powerful telescope, the VLT (Very Large Telescope). The results obtained with VLT give on average more than one scientific publication daily and made a number of astronomical discoveries: double star Achenar, the bluest and hottest known, first image of an exoplanet, black areas in the center Milky Way, and much more. An interesting fact: the four telescopes of the station were named in the Mapudungun language - Antu(Sun), Kueyen(Moon), Melipal(South Cross), Yepun(Day Star). The Paranal station is run by the European Southern Observatory.

The detail of the images obtained with this telescope will be better than that of the Hubble orbital telescope.

The ALMA (Atacama Large Millimeter/submillimeter Array) station is also widely known, the largest astronomical project of our time today, in which partners from East Asia, North America, Europe and Chile.

Paranal Station, home to the VLT telescope

But very soon it will be surpassed by an even more advanced and innovative model, the E-ELT telescope (Extremely Large Telescope), which is commonly called the most important project of our time in astronomy. A step into the future, an even more advanced and innovative model. Construction has already begun on Amazones Hill in the Atacama region. The telescope is planned to be put into operation in 2022.

The stations look like interplanetary ships from a science-fiction movie saga; it’s hard to believe that someone comes here to work on a daily basis.

Experts are already calling it a real technical breakthrough, in particular due to the gigantic size of the lens (39 meters is no joke). Also noteworthy is the special adaptive optical design of the lens consisting of five mirrors, which allows you to get the clearest pictures possible. Speaking in simple language, the detail of the images obtained with this telescope will be better than that of the Hubble orbital telescope.

Bond, James Bond

The astronomical stations in Atacama look like interplanetary ships from a science-fiction movie saga. I find it hard to believe that anyone comes here to work on a daily basis. The view of the Parnal station is completely alien, like all the surrounding structures for the needs of global astronomy. Also in such scenery as the expanses of the Atacama! It is not surprising that it was the Paranal Observatory that appeared in the film about agent 007 James Bond “Quantum of Solace”, namely the residential building for employees of the Residence station.

Hotel ESO Hotel at Paranal station, flashed in the film about agent 007 “Quantum of Solace”

Visiting the observatories of Chile

Every year thousands of people from all over the world come to the desert, attracted by its “star” glory. It is not surprising that astronomical tourism is a major source of income. Oddly enough, much less people We have heard more about the local Martian landscapes of Death Valley than about the most powerful telescope in the world. I have been convinced of this many times.

Even in the vastness of the desert, the remains of meteorites are often found. There is even a corresponding museum in .

In total, on the territory of the Atacama this moment houses about 40 percent of all space telescopes in the world. Of course, not all telescopes belong to Chile. Rather, only a small part of them, and the majority - 15 countries within the European Southern Observatory. With the construction of the new Giant Magellan Telescope, Large Synoptic Survey Telescope (LSST), the figure will increase to the already mentioned impressive 70 percent.

You can visit Paranal, ALMA and La Silla stations (also run by the European Southern Observatory) on Saturdays and Sundays. You must submit applications in advance; you often have to get on the waiting list. You will have to get there on your own, since there is no organized transport or transportation to the stations. If you are very lucky, then perhaps during an excursion to one of the stations you will even be allowed to press the button on the white tent, behind which the “greatest eye of humanity” lurks.

Or you can go for a night walk through the dunes of the driest desert in the world, and see how the stars illuminate the bizarre sharp peaks. A place so similar in outline to Mars is suited to a scattering of bright stars. Once we organized a custom night astronomical jeep safari for a group of tourists. According to their reviews, it was unforgettable.

Observatories in Santiago

They exist. The observatory El Observatorio Astronómico Nacional on the Calán hill regularly conducts night tours for everyone, except in February and winter (June to August). The observatory has two telescopes at its disposal - not VLT level, of course, plus you won’t see the same sky here as in Atacama, but it’s still interesting. During a two-hour visit you can learn a lot about the world of astronomy, but it’s better to sign up a month in advance. The star of the observatory is its employee Roberto Antezana, he is known for his photographs of the night sky and colorful sunsets; if you wish, you can easily make friends with him on a social network.

Meanwhile in the desert...

To see how brightly the stars shine in the night sky of Atacama - it seems that you can reach them with your hand - you just need to go outside. The astronomical map of the constellation is built before your eyes. Seeing a rare constellation while walking outside your hotel sounds good.

Every day from different points deserts make new discoveries in the world of stars. New constellations are being put on the map. Water is found on planets. Possible signs of past, present and future life. Heavenly life is in full swing. And the observatories of Chile open its magical curtain for us.

Guardians of the Galaxy. Observatories of Chile was last modified: July 7th, 2017 by Anastasia Polosina

Planet X - Nibiru, about which so much has been said and written last years and decades around the world, was finally discovered in the night sky of the Southern Hemisphere on May 31, 2017. Professional Chilean astronomer Roberto Antezana did it. He initially saw the strange planet with the naked eye and observed for 35 minutes, then he continued observing through a powerful telescope and took pictures of this planet, which he posted on his Facebook page. He also recorded the coordinates of this planet, which he shared with his colleagues.

Now about those signs that allow us to identify this planet as Planet X - Nibiru.

The most characteristic feature of the newly discovered planet is the V-shaped plume, described and captured in a photo taken by Roberto Antezana. This trail or tail makes this planet look like a giant comet.

But it is precisely this train that is characteristic hallmark planet X - Nibiru. In the cultures of many ancient civilizations (Sumerian, Egyptian, Persian, Mayan), planet X - Nibiru is depicted precisely in the form of a Winged Ball - a ball with two wings on the sides. Here is what the discoverer of the planet Nibiru, Zecharia Sitchin, writes about this:

“Wherever archaeologists found the remains of ancient civilizations of the Middle East, they encountered the symbol of the Winged Ball, the image of which dominated the walls of temples and palaces, on bas-reliefs carved into rocks, on cylinder seals and frescoes. This symbol accompanied kings and priests - it was carved above thrones, “hung” over the rulers in scenes of battles, and was present in the decoration of chariots. The symbol was decorated with clay, metal, stone and wooden objects. The rulers of Sumer and Akkad, Babylon and Assyria, Elam and Urartu, Mari and Nuzu, Mitanni and Canaan - all. they worshiped this symbol. The Hittite kings, the Egyptian pharaohs, the Persian shahs proclaimed this symbol (and what it stood for) as sacred and supreme. This veneration persisted for several millennia.

The basis of religious beliefs and astronomy ancient world was the belief that the Twelfth Planet, or Planet of the Gods, remained in solar system and that as it moves in orbit, it periodically approaches the Earth. The pictogram for the Twelfth Planet, or "planet of intersection", was a cross.

This cuneiform sign, which also meant "Anu" and "divine", became the letter "tav" in Semitic languages, which means "sign".

Indeed, all the ancient peoples of the Middle East considered the periodic approach to the Twelfth Planet a sign foreshadowing unrest, great changes and the offensive new era. Mesopotamian texts indicate that the periodic appearance of the planet was an expected and predictable phenomenon that could be observed:

The Great Planet: Dark red when appearing, Divides the Heavens in half, And receives the name Nibiru."

But what is this V-shaped train?

ZetaTalk gives us an answer to this question, which there is no need to present here:

"During the journey of a giant comet in space, its tail encounters almost no resistance. It consists of attracted and pulled gravitational force fragments that fly behind the comet not only from the moment of formation, but also from the time when it flew past them in space. Depending on the size and composition of the formation, dust, gases, rocks, boulders and planetary satellites are found at any given point in the tail. In space, in the long arc of the trajectory that the 12th Planet describes as it soars away from the Earth and floats into the darkness of outer space, nothing else affects him. But when a comet enters your Solar System, everything changes. sunny wind and the bombardment of radiation that your eye cannot see as light can see, pushes the tail outward, away from the Sun. Therefore, the comet's tail - dust, gases, rocks and boulders - all together - fans the Earth. What is the result? The comet's satellites stay close to it, and although they do not reach the Earth, everything else makes a massive attack on the Earth's atmosphere."

Roberto Antezana also reported that the V-shaped trail of the unidentified planet consists of rocks.

Roberto Antezana also discovered the satellites of the comet-like planet X - Nibiru (a string of moons) inside the trail, calling them "incredible structures."

Antezana reported that the planet is approaching the Earth, and their trajectories are either close or intersecting. The same is known about planet X - Nibiru.

Finally, another important sign that Roberto Antezana discovered exactly planet X - Nibiru is that it is recorded precisely in the skies of the Southern Hemisphere.

Here's what I wrote about this in the chapter "Identifying Planet X":

“Few people know the fact that on August 30, 1990, the historic meeting between Harrington and Sitchin took place in Harrington’s office in Washington.

This meeting took place after Harrington read Sitchin's works and realized that the Tenth Planet (Planet X) of his search and the planet Nibiru of the ancient Sumerians were one and the same planet. The meeting with Sitchin only strengthened this confidence. All the puzzle pieces fit together. The so-called “Pioneer anomaly” also became clear to Harrington. It became clear to Harrington that the reasons for the anomalous deviation of the Pioneers (as well as the later discovered deviations of the Cassini, Rosetta, Galileo probes) are the same as the reasons for the disturbances in the orbits of Neptune and Uranus: the influence of a very massive celestial body what Planet X is - Nibiru. After a discussion with Sitchin, the probable trajectory of the planet Nibiru became clearer: it should have been looked for in the skies of the Southern Hemisphere below the ecliptic plane. And after this, Harrington applies to use the telescope in Black Birch (New Zealand).

American astronomer Robert Harrington was killed immediately after submitting this application. The secret world government, which previously ordered the assassination of US Secretary of Defense James Forrestal (1947) and then US President John F. Kennedy (1963), has now ordered the assassination of Robert Harrington. He was killed by injection of a fast-moving cancer. Harrington died on January 23, 1993, in terrible agony in front of his family, friends and colleagues. This was a signal to all astronomers not to touch on any more forbidden topics."

In 2006, the US Government installed the South Pole Telescope in Antarctica to observe planet X - Nibiru in the skies of the Earth's Southern Hemisphere. After this, representatives of the global elite, including the Russian one, began to frequent Antarctica. In 2007, Antarctica was visited by the director of the FSB of Russia Nikolai Patrushev, the first deputy director and head of the Border Service of the FSB of Russia Vladimir Pronichev, the vice speaker of the State Duma, the famous Russian polar explorer Artur Chilingarov and the head of the World Meteorological Organization, head of Roshydromet Alexander Bedritsky. In 2016, Patriarch Kirill (Gundyaev) visited Antarctica. What they were looking at there - penguins or planet X - Nibiru through SPT - we still don’t know.

Be that as it may, on May 31, 2017, planet X - Nibiru was discovered. And perhaps this discovery will be the most important discovery not only this year, but throughout the 21st century.

Candidate of Physical and Mathematical Sciences Kirill Maslennikov, Pulkovo Observatory (St. Petersburg)

I am a professional astronomer-observer at the Pulkovo Observatory. Over the years of work, I was lucky enough to carry out observations on a variety of instruments, including the largest in the world at the time of its construction, the 6-meter BTA (Large Azimuth Telescope, Special Astrophysical Observatory of the Russian Academy of Sciences, North Caucasus) and the largest in Eurasia, also at the time of construction, the 2.6-meter reflecting telescope named after G. A. Shain (ZTSh, Crimean Astrophysical Observatory). I visited such places famous for their astroclimate as the observatories on the Maidanak plateau (Uzbekistan) and in the Pamir mountains in Tajikistan: Sanglokh and Shorbulak. And yet, visiting Cerro Paranal and the Chajnantor plateau was unforgettable for me. I hope to convey this impression - at least in part - to readers. It seems to me that many will be interested in knowing what a real modern observatory is like.

A unique system of four lasers of the VLT “unit”, which creates as many as four artificial “stars” for the adaptive optics system at an altitude of 90 km. Photo: ESO.

Panorama of La Silla Observatory. Photo by Kirill Maslennikov.

The main telescope of the La Silla Observatory, the diameter of the main mirror is 3.6 m. Photo: ESO.

A telescope of new technologies, the diameter of the main mirror is 3.6 m. It is located in a movable rectangular pavilion that rotates with it. This telescope was the first to implement the principle of active optics. Photo: ESO.

The HARPS spectrograph at La Silla Observatory is one of the most famous operating astronomical instruments in the world. Photo: ESO.

One of four VLT auxiliary telescopes with a 1.8 m diameter mirror. It can ride on rail tracks. Photo by Kirill Maslennikov.

One of the four main “units” - telescopes that make up the VLT complex. The diameter of the main mirror of each “unit” is 8.2 m. Photo: ESO.

Fiber optic channels in underground tunnels. Through these channels, all radiation fluxes received by each of the telescopes are reduced to one receiver. This allows them all to work as one megatelescope or as an interferometer. Photo by Kirill Maslennikov.

The VLT “unit” laser creates an artificial “star” at an altitude of 90 km, with the help of which the atmospheric turbulence profile is measured for an adaptive optics system that allows correcting image distortions. Photo: ESO.

VLT images of Neptune with (left) and without (center) adaptive correction, next to a scaled-down image from the Hubble Space Telescope (right). Photo: ESO.

OmegaCam live imaging camera. Consists of 32 CCD matrices. Photo: ESO.

Under the glass dome of the La Residencia hotel there is a winter garden and a swimming pool. Photo by Kirill Maslennikov.

Hotel "La Residencia" at the foot of Cerro Paranal, where the observatory staff live. The four-story building seems to be immersed in the mountainside. Photo: ESO.

ALMA is a composite radio telescope operating in interferometric mode, consisting of fifty-four 12-meter and twelve 7-meter parabolic antennas. Photo: P. Horálek/ESO.

The 100-ton antenna dishes are moved from place to place by a 28-wheel transporter designed specifically for ALMA. Photo: ESO.

Science and life // Illustrations

An impressive scientific result from the ALMA telescope - an image of a forming planetary system around the star HL Tauri in millimeter waves(image colors are relative). The structure of the protoplanetary disk and the gaps in it, apparently corresponding to the orbits of condensing planets, are clearly visible. The distance to the star is 450 light years. Illustration: ESO.

But first we need to clarify two issues. First: what kind of organization is ESO, uniting European astronomers (albeit without Russia, to my great regret, it seems to me, for both sides)? And second: why was it necessary to build indescribably expensive observatories on the other side of the globe, in Chile, to observe the stars, which are visible from any hillock at night? Both of these issues are closely related.

The unique astroclimate of Chile and the creation of the European Southern Observatory

By the sixties of the last century, the largest revolution since the time of Copernicus took place in astronomy (it is still ongoing). On the one hand, it became possible to observe exceptionally faint and distant objects; on the other hand, infrared and ultraviolet waves were added to traditional optical waves, and behind them a transition to other spectral ranges was already looming. Astronomy was becoming all-wave. At the same time, it became clear that obtaining unique astronomical data requires a rather rare combination of geographical and climatic factors. And, no matter how expensive and troublesome it was, we had to look around the globe for rare places where:

Cloudy weather would be rare;

The air would be clear, free of aerosols, and calm, with as little turbulence as possible;

There would be no sources of artificial lighting - “light pollution” - around.

The combination of all these factors was called “astroclimate,” and expeditions equipped with special measuring equipment began to be sent to search for places with a good astroclimate. A large telescope is an expensive instrument, and installing it in a place where it will be used half-heartedly is simply throwing money away.

It turned out that there is a special region in the world with an extraordinary astroclimate: the Chilean Andes in South America. Chile is a strip of Pacific coastline stretching approximately 4,500 km from north to south and only 400 km from east to west. A young volcanic chain stretches almost this entire length, blocking the path of air masses with Pacific Ocean. The northern half of Chile is almost entirely occupied by the highest desert in the world - the Atacama. All astroclimatic parameters here turned out to be extremely favorable: a fantastic number of clear nights per year (only about 10% of the night time is unsuitable for observations); very high optical transparency of the air and a complete absence of “light pollution” (there are no large settlements); incredibly calm atmosphere (typical size of a “shake disk”, i.e. angular size the spot to which the point image of a star is blurred by atmospheric turbulence is usually less than one second of arc - three to four times less than in average conditions), and, finally, extremely low air humidity (only 0.1-0.2 mm of precipitated water in the air column versus the average several tens of millimeters).

As a result, astronomers flocked to Chile, where expeditions from the countries of the New and Old Worlds identified several places for the construction of observatories. But a modern large observatory, located in a remote, deserted and often inaccessible area, is simply in volume construction work and accompanying infrastructure is a very expensive object. And if you add to these expenses the cost of what the observatory is being built for - giant astronomical instruments, then the resulting amounts reach billions of dollars. No country in Europe could or can afford this. This is how the idea of ​​the European South Observatory (ESO) emerged: an organization that could accumulate funds from interested European countries to build observatories in the “promised land” of astronomers.

This idea paid off. In 1962, the Declaration on the Establishment of ESO was signed by representatives of five countries; it now has sixteen members. In fifty-six years, ESO has opened three observatories in Chile that have become the world's leading research centers, and is now building a fourth, which in six years will be home to the largest optical telescope in history.

It is worth noting that ESO pays great attention to familiarizing the public with the results of its work. Such scientific and educational activities are called in English “public outreach activities” - the exact Russian equivalent of this concept apparently does not exist, and not by chance. In our scientific institutes, it is not customary to regularly report to the general public on the progress of research, and, of course, the academic authorities are shown “the product face to face.” And in the West this is common practice, at least in the field of astronomy and space research. Both the Hubble Space Telescope and the European Space Agency issue weekly press releases. The existence of such a “propaganda” system is important because all these major scientific institutes exist at the expense of taxpayers, and in order for funds to continue to be allocated for extremely expensive scientific projects, researchers have to “advertise” their achievements in every possible way.

The ESO website (www.eso.org) is very impressive and is available in nearly thirty languages. Thanks to the efforts of the author of this article, the Russian version of the ESO website has existed for seven years (https://www.eso.org/public/russia). It is with good reason that ESO positions itself as one of the world's astronomical centers to translate its weekly press releases into all these languages. latest achievements and ESO news, there is a team of volunteers called the ESO Network - ESON. As a member of ESON, I received an invitation to visit the ESO observatories.

La Silla Observatory

And then an exciting moment came when I noticed the white domes of telescopes on a distant peak. Hello La Silla! This mountain, 150 km from the city of La Serena, was the first point chosen in the sixties by expeditions of European astronomers to place ESO telescopes. When we got closer, we saw on the neighboring peak of Las Campanas the towers of another major observatory - the Carnegie Institution (USA). There are two telescopes with a main mirror with a diameter of 6.5 m and construction has begun on a giant instrument with an aperture of 25 m, which in the next decade will apparently be the third largest in the world (after the E-ELT and the Thirty Meter Telescope).

La Silla looks quite traditional: a whole family of towers different sizes and forms. The “main caliber” of the observatory - a telescope with a main mirror with a diameter of 3.6 m - is quite large by the standards of the last century, but by today's standards it is rather medium-sized. Still, there are two legendary instruments on La Silla that are worth talking about.

One of them is the famous NTT, the New Technology Telescope, which appeared here in March 1989. Its size does not amaze the imagination (its main mirror is also 3.6 m in diameter), but it was on it that a number of revolutionary discoveries in telescope construction were tested in the early 1990s. It is mounted according to the altazimuth principle, that is, it can be rotated both in height and in azimuth (although our 6-meter BTA was a pioneer in this). But it is placed not in an ordinary tower with a rotating dome, but in a movable rectangular pavilion, integral with the telescope and rotating with it. Thanks to this, the space under the dome disappeared, and with it the eternal concern of astronomers about reducing turbulent air flows in it, which reduce the quality of images. For the small remaining space inside the pavilion, it was possible to design a ventilation system in which turbulence practically disappeared. The main mirror of the telescope differs from ordinary massive giant mirrors in its thickness: only 24 cm, 15 times less than the diameter! This not only made the telescope much lighter, but, most importantly, made it possible to implement the principle of active optics for the first time in astronomy. On the back side, 75 electromechanical microdrives - “actuators” - are mounted into the thickness of the mirror, with the help of which it is possible to change the curvature of the mirror surface on a microscopic scale. In this way, it is possible to constantly compensate for distortions in the shape of the mirror surface caused by relatively slowly changing factors: temperature deformations, deflections due to variable orientation of gravity at different positions of the mirror, etc. And this significantly improves the quality of the image produced by the telescope. Now active optics systems and flexible thin mirrors are used in almost all large telescopes.

If NTT is more of a historical monument, although observations on it continue, then the second “wonder of the world” at La Silla, the HARPS spectrograph, is one of the most famous operating astronomical instruments in the world. He is called the "planet hunter." He holds the absolute record for the number of exoplanets discovered by the radial velocity method and for the accuracy of velocity measurements. The idea of ​​the method is simple: if a star has a planet, then, revolving in its orbit, it attracts the star towards itself, causing the star to shift - not much, of course, since its mass is much greater than the mass of the planet. It is almost impossible to notice these displacements directly, from the shift in the coordinates of the star - they are so small. But the Doppler shifts of lines in the spectrum of a star - to the red side, when the planet “pulls” the star away from us, or to the blue, when it pulls it in our direction - turns out to be noticeable! This is where the excellent parameters of this spectrograph come into play - it is capable of recording the speed of a star at 0.5-1.0 m/s, which corresponds, for example, to the speed at which a one-year-old baby crawls on the floor. Such fantastic accuracy is achieved by a number of special technical tricks, the simplest of which are placing the spectrograph in a vacuum chamber and deep cooling of the light-sensitive elements.

Of course, HARPS is a magnificent instrument, and La Silla is a large, modern observatory. But you didn’t have to cross the ocean to look at something like this - there are such observatories in Europe. But, if you drive another 600 km to the north, deep into the Atacama Desert, you find yourself in a different era of the development of astronomical technology. Here, on the top of Cerro Paranal, a Very Large Telescope, VLT (Very Large Telescope), created by the joint efforts of European science and industry, is installed.

Paranal Observatory

The top of the mountain has been cut off and turned into a flat concrete platform. There are four futuristic rectangular towers on it, arranged asymmetrically, but in a certain order: three in a line, one on the side. When looking at them, the epithet “cyclopean” comes to mind - perhaps because the Cyclops is famous for its single eye, and inside each tower there is a giant “eye”: an altazimuthal reflector with a main mirror a little over 8 m in diameter. These are “units” - the main telescopes of the complex. In addition to them, there are four more auxiliary telescopes with mirrors 1.8 m in diameter. They are installed in compact spherical domes that can travel along straight rail tracks laid on the platform. In a separate building - Central control panel. All this together is a Very Large Telescope.

The main “trick” is that the eight telescopes of the complex can work either individually (which in itself is not surprising) or in various combinations, to the point that all together they can form a single megatelescope. For this purpose, fiber optic channels are laid in underground tunnels. With their help, all fluxes of radiation received by each of the telescopes are reduced to one receiver. This happens in two modes. You can simply merge all the streams together, increasing the intensity of the received radiation and thereby registering weaker objects. But in this case, information about the phase of light waves will be lost. But if this information is preserved, it turns out that all the mirrors receiving radiation serve as fragments of the same giant pupil. And we will be able to distinguish image details as many times finer than those obtained with a separate telescope, as many times the distance between the mirrors of these telescopes (the size of our giant pupil) is greater than the diameter of a separate mirror. These are the laws of physical optics: due to diffraction at the edges of the pupil, the telescope builds an image of the star not in the form of a point, but in the form of a disk of finite size, surrounded by concentric rings of decreasing brightness. The size of this disk is inversely proportional to the diameter of the pupil.

In order for all the mirrors to truly become part of a single pupil, it is necessary to ensure that all four signals arrive at the receiver in the same phase. The phase can be adjusted by increasing or decreasing the optical paths of the signals. But this must be done with very great accuracy, because the wavelength of light in the visible range is half a thousandth of a millimeter. Therefore, the slightest temperature changes or vibrations can disrupt phasing.

The method I have just described is called optical interferometry, and several telescopes forming a single instrument are called interferometers. Thus, the VLT can operate in VLTI: Very Large Telescope Interferometer mode. It is for the implementation of this mode that the possibility of moving auxiliary telescopes along rail tracks is provided: after all, maximum resolution is achieved not over the entire field, as would happen if we had a real huge continuous mirror, but only along the axis connecting the individual mirrors. Movable telescopes make it possible to orient this axis so that it passes through the structurally important details of the observed object.

Here is just one example of the delicately precise observations made using interferometry: the results of measurements of the motion of stars in the immediate vicinity of a giant supermassive black hole hidden in the center of our Galaxy, published in the summer of 2018. It has long been suspected that there is a black hole with a mass of about 4 million Suns at the center of the Galaxy, in particular due to the powerful X-ray radiation coming from there. But in optics and in the infrared range it remains invisible, and the only optical effect with which it betrays its presence is the distortion of monstrous gravitational field trajectories of stars close to it. Until the very end of the last century, it was impossible to trace these curved orbits - too high an angular resolution was required to see at a distance of almost thirty thousand light years the movements of stars located only 120 astronomical units from the black hole. This is the outer size of the Kuiper Belt in the Solar System! And now on VLTI with the GRAVITY receiver, to solve this problem, it was possible to achieve a resolution of approximately two milliarcseconds. With this resolution, a telescope would be able to spot, say, a pencil on the surface of the Moon! An important result of this work was, in particular, the confirmation of predictions obtained with high accuracy general theory relativity regarding the orbital properties of stars close to the gravitational monster. This is the first time such a test of the theory has been possible on a galactic scale - until now it was possible only within the solar system.

However, it is very difficult to implement the interferometry mode for optical waves: phasing accuracy can only be maintained for several (at best 10-20) minutes. Therefore, most of the time, VLT telescopes still work separately. But even in this seemingly ordinary mode, they have one remarkable feature: the VLT “units” (more precisely, so far on one of them, the fourth) are installed, perhaps, the most advanced adaptive optics systems used on large telescopes in the world.

When talking about the NTT telescope, I already mentioned active optics - a computer-controlled change in the shape of the flexible main mirror. But this method is only suitable for compensating for mirror surface distortions caused by slowly changing factors. Meanwhile, the main enemy of astronomers, negating the enormous potential resolving power of giant mirrors, is atmospheric turbulence. Turbulent air flows blur the images of stars, deform the flat wave fronts coming from the stars to the Earth, and as a result, instead of diffraction images, the angular size of which can be made very small by increasing the size of the “pupil”, we see through the telescope so-called jitter disks - shapeless blurry “blobs” " Under normal atmospheric conditions, the average size of such a “blob” is about 2-4 arc seconds; in places with a very good astroclimate it can drop to half an arcsecond. And this despite the fact that the theoretical resolution of, say, an 8-meter telescope is 100 times higher! It was very difficult to come to terms with this. For a while, it seemed that if we climbed high enough into the mountains, we would leave turbulent layers of the atmosphere below. According to another point of view, the main thermal vortices occur in the ground layer, and one can try to cut them off by hanging wide “fields” on astronomical towers so that the tower seems like a huge “mushroom”. Neither idea came to fruition, and the only way To get rid of atmospheric distortions in images of stars seemed to be the launching of telescopes into near-Earth space, beyond the atmosphere.

This is where active optics methods found their application. At first it seemed that it was impossible to use them to compensate for atmospheric distortions due to the high frequency of the latter: the characteristic time of “freezing” of the atmosphere is approximately 0.01 s. To measure the wavefront profile, calculate the deformations of a flexible mirror necessary to align it, and, finally, bend the mirror using actuators in a hundredth of a second - this task seemed absolutely unrealistic. But in two or three decades it was solved! Three points turned out to be key. Firstly, it is not the huge, massive primary mirror that can be deformed, but a thin optical element in the converging beam or exit pupil (in the case of VLT, this is a flexible secondary mirror). Secondly, the performance of control computers has increased many times over. And finally, thirdly, an ingenious method was invented for measuring the profile of atmospheric turbulence precisely in the direction of the star under study. In fact, it is impossible to use the image of the star itself to measure atmospheric distortions - very faint objects are usually observed, and in order to properly probe the atmosphere, a lot of light is needed. And we need the light of an object in order to study it, and not waste precious photons measuring turbulence in the earth’s atmosphere! Hope that at a distance of two tens of seconds from the object there will be bright Star, it’s not worth it - this happens extremely rarely. But it is useless to use a bright star somewhere far away - there the profile of the wave front will be completely different. What to do?

An ingenious solution to this impasse was invented by Princeton physicist Will Happer in the midst of " star wars"between the USSR and the USA - naturally, then this method was classified and only 20 years later it began to be used not for aiming laser weapons, but for astronomy. The idea is that a powerful laser is installed on the telescope, which excites atoms in a layer of sodium gas at an altitude of 90 km in the atmosphere with a well-focused beam. Sodium begins to glow, and by pointing the laser at the desired point in the sky, we get a bright luminous star-shaped point there - an “artificial star.” Since all turbulent layers lie below 90 km, we can use this source to probe wavefront parameters in a small area of ​​the sky where the object we are studying is located.

The task of correcting atmospheric distortions still remains fantastically complex - let’s not forget that the characteristic “freezing time” of turbulent cells is equal to a hundredth of a second! During this time, it is necessary to analyze the nature of atmospheric distortions in the artificial star, calculate the appropriate compensations for the flexible optical element and work them out mechanically. And yet, the speed of modern control computers and the perfection of the optical-mechanical part of the system make it possible to achieve this! And now most of the world's large telescopes are equipped with “laser guns” that shoot their beams into the night sky during observations. But the VLT has distinguished itself here: one of the main telescopes, UT4, has recently installed an adaptive optics system, including not one, but four powerful lasers, each of which sends a 30-centimeter-thick column of intense orange light into the sky. In the field of view next to the object, not one, but four “artificial stars” now glow, which, of course, increases the accuracy of turbulence measurements.

The results of using this system are very impressive. This summer, for example, it was tested at VLT in a special “laser tomography” mode with the MUSE receiver: in combination with the GALACSI adaptive optics module. In wide field mode, correction of distortions in a field with a diameter of one arc minute is provided with a pixel size of 0.2x0.2 "". Small Field mode covers just 7.5 arcseconds, but at much smaller pixel sizes: 0.025x0.025"". In this case, the maximum theoretical resolution of the telescope is realized.

We could talk for a long time about the masterpieces of astronomical technology at the Paranal Observatory. All VLT telescopes are equipped with unique receivers specially developed by ESO: spectrographs, polarimeters, direct imaging cameras (the largest of them, OmegaCam, consists of 32 CCD arrays with a total size of 26x26 cm and a volume of 256 million pixels with a field of view of one square degree). About each of these remarkable instruments, as well as about the two largest wide-field telescopes in the world, VST and VISTA, installed on Paranal, on which star maps and reviews could be written separately. But before we leave Paranal and head deeper into the Atacama Desert to the ALMA observatory, I would like to tell you a little about how ESO employees: astronomers, engineers and support staff live here.

Applications for observing time on ESO instruments are reviewed by a special scientific committee, which draws up an observing program for the year ahead. In principle, any astronomer can apply for this programme, but scientists from ESO member countries are of course given preference. However, if an application is accepted, this does not mean that the specialists who submitted it must fly to Chile. For several decades, observations at large telescopes have been carried out remotely - the authors of the application participate in them using modern communication channels. Nevertheless, professionals must still directly conduct on-site observations and operate the telescope and receivers while in the central control room. Therefore, a group of astronomers is constantly present on Paranal, whose task is to carry out program observations. They work on a “shift basis”, in shifts, going “to the mountain” once every two or three months. These specialists are recruited mainly in Europe, in ESO member countries, although they also include Chilean astronomers. But, of course, they do not fly every two months from Europe - they move to the capital of Chile, Santiago, for the duration of the contract, many with their families. In addition, at Paranal, as at any large observatory, there are many technical employees: electronics engineers, mechanics, drivers. How is their life organized?

Looking from the VLT observation platform, far below, at the foot of Cerro Paranal, a spherical glass dome can be seen. This is the roof of the La Residencia hotel. The entire four-story building seems to be immersed in the mountainside; the outer wall with windows looks in the direction opposite to the top. Inside, everything is provided so that people who work hard under difficult time conditions and often in very harsh weather conditions can relax. Under a wide glass dome there is a winter garden with tropical plants, a large swimming pool, sports equipment, and a 24-hour restaurant. It feels like we're on a big cruise ship. The remarkable building has already been awarded an international award and even appeared in the movies as the lair of the “main villain” in one of the James Bond films (“Quantum of Solace”).

But the time has come to go further - north again and then away from the ocean, into the mountains. 500 km from Paranal, at an altitude of 5000 m above sea level, at the foot of the Licancabur volcano lies the high plateau of Chajnantor, on which perhaps the largest-scale ground-based astronomy project in history was implemented: ALMA.

At the very beginning of our story, among the main factors influencing the quality of the astroclimate, we mentioned low humidity. The entire territory of the Atacama Desert is characterized by abnormally low air humidity, but when you climb to a very high altitude, the dryness becomes truly incredible: if you settle, “squeeze” all the moisture from the column of air from the ground layer to the airless outer space, then the height of the resulting “puddle” will be less than a millimeter. There are very few places like this on the globe. The biggest benefit from such low humidity comes at the wavelengths most susceptible to absorption by water vapor: millimeter and submillimeter wavelengths. This is already the radio range: telescopes operating at such waves have the form of parabolic dish antennas. Radiation in this part of the spectrum carries information about cold regions of the Universe - regions of star formation hidden by a dense dust curtain through which visible light does not pass, about protoplanetary accretion disks, mysterious galaxies of the early Universe, visible at such gigantic distances that, as a result of the red shift, their radiation went far into the long-wavelength part of the spectrum. The solution to many key problems in the science of the Universe is hidden here, and yet it is precisely for this radiation that in ordinary places the Earth’s atmosphere represents an almost impenetrable barrier.

And at the beginning of this century, ESO, in cooperation with the National Radio Astronomy Observatories of the USA and Japan, began to build a grandiose “array” here: a composite radio telescope, like the VLT, operating in interferometric mode, which, due to the significantly longer wavelength in this spectral range, is implemented much more reliably and more efficient. Thus was born ALMA - Atacama Large Millimeter/sub-millimeter Array. The scale of the project turned out to be truly stunning: an array of telescopes on a high mountain plateau consists of fifty-four 12-meter and twelve 7-meter parabolic antennas, capable of moving and forming interferometric bases over an area 16 km across. After 15 years of construction, which required the entire power of industry in Europe, North America and South-East Asia(Canada, Taiwan and Korea also joined the project), the giant phased antenna array has been operating for the third year full force. The project cost was about $1.5 billion.

The 100-ton "plates" are carried from place to place by two bright yellow 28-wheel transporters designed specifically for ALMA. Their names are “Otto” and “Lore” - they say the designer named them after his little children. The antenna installation process is carried out remotely: the driver, who is also the operator, leaves the conveyor cabin, holding a remote control in his hands, and controls both the movement of the conveyor and the installation of the antenna on a triangular concrete platform with millimeter precision.

The primary processing of data coming from the antennas is carried out by a supercomputer installed here - the so-called correlator. This is one of the most powerful computers on the globe: its performance is 17 quadrillion operations per second. Overnight, the grid collects from half to one and a half terabytes of information, the storage and distribution of which in itself poses a serious problem.

The conditions under which astronomers and engineers work on the Chajnantor plateau are much harsher than on Cerro Paranal. Here is a “Martian” landscape - bare soil covered with volcanic bombs, almost no vegetation. 5000 m above sea level is a serious altitude; people at it quickly begin to experience oxygen starvation, “altitude sickness.” Therefore, all technical services, living and working premises, laboratories, offices are located in the base camp: the Technical Support Center at an altitude of about 3000 m. The shift ascends to the scientific site for no more than 8 hours. Almost everyone I saw on the plateau uses oxygen machines. Visitors who do not take part in the work of the shift are raised to the plateau for only 2 hours. Before getting up, everyone undergoes a short medical examination.

The telescope array on the Chakhnantor plateau has only recently been operational, but significant scientific results have already been obtained from it. Perhaps the most impressive of them is the image of the forming planetary system around the star HL Tauri. Another very important area ALMA works - studies of objects of the “early Universe”, galaxies located on the far edge of the region of outer space observable from Earth and visible to us in an epoch distant from the moment big bang just for a billion years. In the spring of 2018, publications appeared about ALMA observations of a massive merger of galaxies at a distance of more than 12 billion light years. These observations challenge generally accepted ideas about the evolution of galaxies.

Construction of the ELT supertelescope

A story about ESO's observatories in Chile would not be complete without adding another exotic toponym to La Silla, Cerro Paranal and the Chajnantor plateau: Cerro Armazones. On this peak, 20 km from Paranal, construction is already underway on a platform for the installation of the ELT - Extremely Large Telescope, the largest telescope in the world. In Russia, this name is usually translated as “Extremely Large Telescope,” although, of course, other translation options are possible.

The ELT will have a main mirror diameter of 39 m. I have already used up all conceivable Russian synonyms for the adjective “huge” in the previous part of my story and now I don’t know what to call this engineering structure. ESO's outreach team has posted a gallery of images on the observatory's website showing the ELT impressively juxtaposed with famous architectural behemoths. But the ELT will leave behind not only them, but also both other astronomical colossi of North American origin under construction: the 25-meter Magellan telescope, which will also be installed in Chile, on Mount Las Campanas, next to La Silla, and the 30-meter telescope ( apparently there weren’t enough adjectives for its name) on the Hawaiian Islands, on the top of Mauna Key.

ESO's new observatory, its fourth, is scheduled to open in 2024. Without a doubt, it will take its place among the scientific wonders of the modern world.