There is a forbidden city in the country. Geography of China. Gugun Museum Complex

From our earthly home we peer into the distance, trying to imagine the structure of the world in which we were born. Now we have penetrated deeply into space. We already know the surrounding area quite well. But as we move forward, our knowledge becomes less and less complete, until we approach an unclear horizon, where in the fog of errors we are looking for barely more real landmarks. The search will continue. The pursuit of knowledge ancient history. It is not satisfied, it cannot be stopped.
Edwin Powell Hubble

At the dawn of the twentieth century, astronautics theorists dreamed that someday humanity would learn to launch telescopes into space. Earthly optics at that time were imperfect, astronomical observations were often hampered by bad weather and sky “lighting,” so it seemed reasonable to send a telescope beyond the atmosphere to study planets and stars without interference. But even science fiction writers could not have predicted at that time how many amazing and unexpected discoveries orbital telescopes would bring.

HAPPY MARRIAGE

The most famous orbital telescope is the Hubble Space Telescope (HST), named after the famous American astronomer Edwin Powell Hubble, who proved that galaxies are star systems and discovered their recession.

The Hubble telescope is one of NASA's four Great Observatories. Having a main mirror with a diameter of 2.4 meters, it remained for a long time the largest optical instrument in orbit, until the European Space Agency launched the Herschel infrared telescope with a mirror diameter of 3.5 meters there in 2009. On Earth of this size, instruments cannot fully realize their resolution: atmospheric vibrations blur the image.

The project could have failed if the telescope had not been originally designed to be serviced by astronauts. The Kodak company quickly produced a second mirror, but it was impossible to replace it in space, and then experts proposed creating space “glasses” - the COSTAR optical correction system from two special mirrors. To install the system on Hubble, the shuttle Endeavor launched into orbit on December 2, 1993. The astronauts performed five challenging spacewalks and brought the expensive telescope back to life.

Later, NASA astronauts flew to Hubble four more times, significantly extending its service life. The next expedition was scheduled for February 2005, but in March 2003, after the Columbia shuttle disaster, it was postponed indefinitely, which jeopardized the further operation of the telescope.

Under public pressure, in July 2004, a commission of the US Academy of Sciences decided to preserve the telescope. Two years later, the new director of NASA, Michael Griffin, announced the preparation of the last expedition to repair and modernize the telescope. It is assumed that after this, Hubble will work in orbit until 2014, after which it will be replaced by the more advanced James Webb telescope.

Hubble was launched into orbit on April 24, 1990, in the cargo hold of the space shuttle Discovery. Ironically, Hubble, when it began operating in space, produced an image worse than a similarly sized ground-based telescope. The reason was an error in the manufacture of the main mirror

WORKING WITH HUBBLE

Anyone with a degree in astronomy can work with Hubble. However, you will have to wait in line. Competition for observation time is high: the requested time is usually six and sometimes nine times greater than actually available.

For several years, part of the reserve time was allocated to amateur astronomers. Their applications were considered by a special committee. The main requirement for the application was the originality of the topic. Between 1990 and 1997, 13 observations were made using programs proposed by amateur astronomers. Then, due to lack of time, this practice was stopped.

The discoveries made with the help of Hubble are difficult to overestimate: the first images of the asteroid Ceres, the dwarf planet Eris, and distant Pluto. In 1994, Hubble provided high-quality images of the collision of Comet Shoemaker-Levy 9 with Jupiter. Hubble found many protoplanetary disks around stars in the Orion Nebula - thus astronomers were able to prove that the process of planet formation occurs in most stars of our galaxy. Based on the results of observations of quasars, a cosmological model of the Universe was built - it turned out that our world is expanding with acceleration and is filled with mysterious dark matter. In addition, Hubble observations made it possible to clarify the age of the Universe - 13.7 billion years.

Over 15 years of operation in low-Earth orbit, Hubble received 700 thousand images of 22 thousand celestial objects: planets, stars, nebulae and galaxies. The flow of data that it generates daily in the process of observations is 15 gigabytes. Their total volume has already exceeded 20 terabytes.

In this collection we present the most interesting of the images taken by Hubble. Theme is nebulae and galaxies. After all, Hubble was primarily created to observe them. In the following articles, MF will turn to images of other space objects.

ANDROMEDA'S NEBULA

The Andromeda nebula, designated M31 in the Messier catalog, is well known to fans of both astronomy and science fiction. And they all know that this is not a nebula at all, but the closest galaxy to us. Thanks to observations of it, Edwin Hubble was able to prove that many of the nebulae are star systems similar to our Milky Way.

As its name suggests, the nebula is located in the constellation Andromeda and is located at a distance of 2.52 million light years from us. In 1885, the supernova SN 1885A exploded in the galaxy. In the entire history of observations, this is so far the only such event recorded in M31.

In 1912, it was found that the Andromeda Nebula was approaching our galaxy at a speed of 300 km/s. The collision of two galactic systems will occur in approximately 3-4 billion years. When this happens, they will merge into one large galaxy, which astronomers call Milky Honey. It is possible that in this case our Solar system will be thrown into intergalactic space by powerful gravitational disturbances

THE CRAB NEBULA

The Crab Nebula is one of the most famous gas nebulae. It is listed in the catalog of the French astronomer Charles Messier as number one (M1). The very idea to create a catalog of cosmic nebulae came to Messier after, observing the sky on September 12, 1758, he mistook the Crab Nebula for a new comet. To avoid such mistakes in the future, the Frenchman undertook to register such objects.

The Crab Nebula is located in the constellation Taurus, at a distance of 6.5 thousand light years from Earth, and is the remnant of a supernova explosion. The explosion itself was observed by Arab and Chinese astronomers on July 4, 1054. According to surviving records, the flash was so bright that it was visible even during the day. Since then, the nebula has been expanding at a monstrous speed - about 1000 km/s. Its extent today is more than ten light years. At the center of the nebula is the pulsar PSR B0531+21 - a ten-kilometer neutron star left after a supernova explosion. The Crab Nebula got its name from a drawing by astronomer William Parsons made in 1844 - in this sketch it closely resembled a crab.

Orbital astronomy has its own history. For example, during full solar eclipse On June 19, 1936, Moscow astronomer Pyotr Kulikovsky ascended on a substratostat to photograph the corona and halo of the Sun. In the 1950s, the Frenchman Audouin Dollfus undertook a series of stratospheric flights in a pressurized cabin specially designed for this purpose, raised by a garland of 104 small balloons, tied to a 450-meter cable. The cabin was equipped with a 30-centimeter telescope, and with its help the spectra of the planets were taken. The development of these experiments was the unmanned Astrolab gondola, with which the French carried out a series of stratospheric observations - its orientation and stabilization system was already created on the basis of space technologies.

For American astronomers, the first step towards orbital telescopes was the Stratoscope program, led by the famous astrophysicist Martin Schwarzschild. Since 1955, flights of Stratoscope-1 with a solar telescope began, and on March 1, 1963, its first night flight carried out "Stratoscope-2", equipped with a high-quality Cassegrain system reflector - with its help, infrared spectra of planets and stars were obtained. The last and most successful flight took place in March 1970. Over nine hours of observation, images of the giant planets and the nucleus of the galaxy NGC 4151 were obtained. The flight was controlled by a team led by Princeton University employee Robert Danielson, who later joined the design team of the Hubble telescope.

PILLARS OF CREATION

The Pillars of Creation are fragments of the gas and dust Eagle Nebula (M16), which can be seen in the constellation Serpens. Hubble took them in April 1995, and this image became one of the most popular in the NASA collection. It was originally believed that new stars were born in the Pillars of Creation - hence the name. However, later studies showed the opposite - there is not enough material there for the formation of stars. The peak of the birth of luminaries in the Eagle Nebula ended a million years ago, and the first young and hot suns managed to disperse the gas in the center with their radiation

The Pillars of Creation are part of our galaxy, but are 7 thousand light years away. They are colossal (the height of the left one is a third of a parsec), but very unstable. Recently, astronomers discovered that a supernova exploded nearby about 9 thousand years ago. The shock wave reached the Pillars 6 thousand years ago and has already destroyed them, but given the remoteness, earthlings will not soon be able to observe the destruction of one of the most unusual and beautiful space objects.

INCUBATOR OF WORLDS

If in the Eagle Nebula the process of birth of new stars has completed, then in the constellation Orion there are no stars yet. The gas and dust Orion Nebula (M42) is located in the same spiral arm of the galaxy as the Sun, but at a distance of 1300 light years from us. This is the brightest nebula in the night sky and is clearly visible to the naked eye. The dimensions of the nebula are large - its length is 33 light years. There are about a thousand stars less than a million years old (by cosmic standards, these are babies) and tens of thousands of stars that are just over ten million years old. Thanks to Hubble, it was possible to discern protoplanetary disks near young stars, and at different stages of formation. By observing the nebula, astronomers can finally get a clear picture of how planetary systems are born. However, the processes occurring in the Orion Nebula are so active that within 100 thousand years it will disintegrate and cease to exist, leaving behind a cluster of stars with planets.

THE FUTURE OF THE SUN

In space you can see not only the birth of worlds, but also their death. The Hubble image taken in 2001 shows the Ant Nebula, which is known to astronomers as Mz3 (Menzel 3). The nebula is located in our galaxy at a distance of 3 thousand light years from Earth and was formed as a result of gas emissions from a star similar to our Sun. Its length is more than a light year.

The Ant Nebula has puzzled astronomers. While they cannot answer the question of why the matter of a dying star flies away not in the form of an expanding sphere, but in the form of two independent emissions, giving the nebula the appearance of an ant, this does not fit well with the existing theory of stellar evolution. One possible explanation: the fading star has a very close companion star, whose strong gravitational tidal forces influence the formation of gas flows. Another explanation: when a dying star rotates, its magnetic field acquires a complex twisting structure, influencing charged particles scattering through space at speeds of up to 1000 km/s. One way or another, close observation of the Ant Nebula will help us see the possible future of our native star.

DEATH OF THE WORLD

Stars that are larger than the Sun usually end their lives by going supernova. Hubble was able to capture several of these flashes, but perhaps the most spectacular is the image of supernova 1994D, which exploded on the outskirts of the disk of the galaxy NGC 4526 (visible in the photograph as a bright spot at the bottom left). Supernova 1994D was not something special - on the contrary, it is interesting precisely because it is very similar to others. Having an understanding of supernovae, astronomers can use the brightness of 1994D to determine its distance and clarify how the Universe is expanding. The image itself clearly demonstrates the scale of the phenomenon - in its luminosity, the supernova is comparable to the luminosity of an entire galaxy.

EATER OF GALAXIES

In space there are not only stars, nebulae and galaxies, but also black holes. A black hole is a region in space in which the gravitational attraction is so strong that even light cannot escape it. It is believed that several types of black holes can be found: those that appeared at the time of the Big Bang, those that were born as a result of the collapse of a massive star, and those that formed in the centers of galaxies. Astronomers say that there are huge black holes at the center of every spiral and elliptical galaxy. But how to see something from which even light cannot escape? It turns out that a black hole can be detected by its interaction with space.

The Hubble image taken in 2000 shows the center of the elliptical galaxy M87, the largest in the Virgo constellation cluster. It is located at a distance of 50 million light years from us and is a source of powerful radio and gamma radiation. Back in 1918, it was established that a stream of hot gases shoots out from the center of the galaxy, the speed inside of which is close to that of light. The length of the jet is 5 thousand light years! A study of the M87 galaxy has shown that the phenomenal density of matter in its center and the monstrous jet can only be explained if we assume that there is a giant black hole there, the mass of which is 6.4 billion times greater than the Sun. The presence of this “eater” of galaxies and periodic ejections of matter from the region next to it prevent the birth of new stars. Astronomers are confident that if there was an ordinary black hole at the center of M87, the galaxy would have a spiral appearance and would be 30 times brighter than ours.

YOUTH OF THE UNIVERSE

The Hubble orbital telescope can serve not only as an optical instrument, but also as a real “time machine” - for example, with its help you can see objects that appeared almost immediately after the Big Bang. In 2004, Hubble, using a new sensitive camera, was able to photograph a cluster of 10 thousand of the most distant and, accordingly, the most ancient galaxies. These galaxies are located at a record distance from us - 13.1 billion light years. If our Universe was born 13.7 billion years ago, then it turns out that the discovered galaxies appeared only 650-700 million years after the Big Bang. Of course, we do not see these galaxies themselves, but only their light, which has finally reached the Earth

Thus, the photograph shows the events that took place in the first billion years of the life of our Universe. According to scientists, at that stage of evolution it was an order of magnitude smaller than its current size, and the objects in it were located closer to each other. Some of the photographed galaxies completely lack the clear internal structure inherent in our galaxy. Others are clearly going through a period of collision, when monstrous gravitational forces give them an unusual shape.

Astronomers conventionally call the region of the oldest galaxies Ultra Deep Field. It is located just below the constellation Orion.

HORSEHEAD NEBULA

The Horsehead Nebula (or Barnard 33) is located in the constellation Orion at a distance of about 1600 light years from Earth. Its linear size is 3.5 light years. It is part of a huge gas and dust complex called the Orion Cloud. This nebula is known even to people far from astronomy, because it really looks like a horse’s head. The red glow of the head is given by the ionization of hydrogen located behind the nebula under the influence of radiation from the nearest bright star - Alnitak. The gas flowing from the nebula moves in a strong magnetic field. The bright spots at the base of the Horsehead Nebula are young stars in the process of formation. Due to its unusual shape, the nebula attracts attention: it is often drawn and photographed. This is probably why the image of the Horse's Head taken by Hubble was recognized as the best according to the results of voting by Internet users.

GALAXY SOMBRERO

Sombrero (M104) is a spiral galaxy in the constellation Virgo, which is located 28 million light years away. The diameter of the galaxy is 50 thousand light years. It got its name due to the protruding central part (bulge) and an edge of dark matter (not to be confused with dark matter!), giving the galaxy a resemblance to a Mexican hat. The central part of the galaxy emits in all ranges of the electromagnetic spectrum. As scientists have established, there is a gigantic black hole there, the mass of which is a billion times greater than the sun. The dust rings of M104 contain a large number of young bright stars and have an extremely complex structure that cannot yet be explained.

The image of the Sombrero Galaxy was recognized as the best image of Hubble according to astronomers interviewed by correspondents of the British newspaper Daily Mail. Probably, by their choice, astronomers wanted to say that knowledge of the Universe does not come down to painstaking study of thousands of photographs of the starry sky, to the construction of graphs and to endless calculations. While we get to know the Universe, we also enjoy its fantastic beauty. And in this we are helped by a unique creation of human hands - the Hubble orbital telescope.

Edwin Powell Hubble is an outstanding American astronomer of the twentieth century. Born November 20, 1889 in Marshfield, Missouri. He died on September 28, 1953 in San Marino (California). Hubble's main works are devoted to the study of galaxies.

  • In 1922, Hubble proposed dividing the observed nebulae into extragalactic (galaxies) and galactic (gas-dust) nebulae.
  • In 1923, the scientist introduced a classification of extragalactic nebulae, dividing them into elliptical, spiral and irregular.
  • In 1924, an astronomer identified the stars from which they consist in photographs of some nearby galaxies, which proved that the galaxies are star systems similar to the Milky Way.
  • In 1929, Hubble discovered a relationship between the redshift in the spectrum of galaxies and the distance to them (Hubble's law). He calculated the coefficient relating the distance to the galaxy to the speed of its retreat (Hubble constant). The recession of galaxies was direct evidence that the Universe arose as a result of the Big Bang and continues to expand rapidly.

Hubble as seen from Space Shuttle Atlantis STS-125

Hubble Space Telescope ( KTX; Hubble Space Telescope, HST; observatory code "250") - in orbit around , named after Edwin Hubble. The Hubble Telescope is a joint project between NASA and the European Space Agency; it is one of NASA's Large Observatories.

Placing a telescope in space makes it possible to detect electromagnetic radiation in ranges in which the earth’s atmosphere is opaque; primarily in the infrared range. Due to the absence of atmospheric influence, the resolution of the telescope is 7-10 times greater than that of a similar telescope located on Earth.

Story

Background, concepts, early projects

The first mention of the concept of an orbital telescope occurs in the book “Rocket in Interplanetary Space” by Hermann Oberth ( Die Rakete zu den Planetenraumen ), published in 1923.

In 1946, American astrophysicist Lyman Spitzer published the article "The Astronomical Advantages of an Extraterrestrial Observatory" ( Astronomical advantages of an extra-terrestrial observatory ). The article highlights two main advantages of such a telescope. First, its angular resolution will be limited only by diffraction, and not by turbulent flows in the atmosphere; at that time, the resolution of ground-based telescopes was 0.5 to 1.0 arcsecond, while the theoretical diffraction resolution limit for an orbiting telescope with a 2.5-meter mirror is about 0.1 second. Secondly, the space telescope could observe in the infrared and ultraviolet ranges, in which the absorption of radiation by the earth's atmosphere is very significant.

Spitzer devoted a significant portion of his scientific career to advancing the project. In 1962, a report published by the US National Academy of Sciences recommended that the development of an orbiting telescope be included in the space program, and in 1965 Spitzer was appointed head of a committee tasked with defining the scientific objectives for a large space telescope.

Space astronomy began to develop after the end of World War II. In 1946, the ultraviolet spectrum was obtained for the first time. An orbiting telescope for solar research was launched by the UK in 1962 as part of the Ariel program, and in 1966 NASA launched the first orbital observatory OAO-1 into space. The mission was unsuccessful due to battery failure three days after launch. In 1968, OAO-2 was launched, which made observations of ultraviolet radiation until 1972, significantly exceeding its design life of 1 year.

The OAO missions served as a clear demonstration of the role that orbiting telescopes could play, and in 1968 NASA approved a plan to build a reflecting telescope with a 3 m diameter mirror. The project was codenamed LST ( Large Space Telescope). The launch was planned for 1972. The program emphasized the need for regular manned expeditions to maintain the telescope in order to ensure long-term operation of the expensive instrument. The Space Shuttle program, which was developing in parallel, gave hope for obtaining corresponding opportunities.

The struggle to finance the project

Due to the success of the JSC program, there is a consensus in the astronomical community that building a large orbiting telescope should be a priority. In 1970, NASA established two committees, one to study and plan technical aspects, the second to develop a scientific research program. The next major obstacle was financing the project, the costs of which were expected to exceed the cost of any ground-based telescope. The US Congress questioned many of the proposed estimates and significantly cut the appropriations, which initially involved large-scale research into the instruments and design of the observatory. In 1974, as part of a program of budget cuts initiated by President Ford, Congress completely canceled funding for the project.

In response, astronomers launched a broad lobbying campaign. Many astronomers met personally with senators and congressmen, and several large mailings of letters were also carried out in support of the project. The National Academy of Sciences published a report emphasizing the importance of building a large orbiting telescope, and as a result, the Senate agreed to allocate half of the budget originally approved by Congress.

Financial problems led to cutbacks, chief among them the decision to reduce the diameter of the mirror from 3 to 2.4 meters to reduce costs and achieve a more compact design. The project of a telescope with a one and a half meter mirror, which was supposed to be launched for the purpose of testing and testing the systems, was also canceled, and a decision was made to cooperate with the European Space Agency. ESA agreed to participate in financing, as well as to provide a number of instruments for the observatory, in return for European astronomers to reserve at least 15% of the observing time. In 1978, Congress approved $36 million in funding, and full-scale design work began immediately thereafter. The launch date was planned for 1983. In the early 1980s, the telescope received the name Edwin Hubble.

Organization of design and construction

The work on creating the space telescope was divided among many companies and institutions. The Marshall Space Center was responsible for the development, design and construction of the telescope, the Goddard Space Flight Center was responsible for the overall management of the development of scientific instruments and was chosen as the ground control center. The Marshall Center contracted with Perkin-Elmer to design and manufacture the telescope's optical system ( Optical Telescope Assembly - OTA) and precision guidance sensors. Lockheed Corporation received the construction contract for the telescope.

Manufacturing of the optical system

Polishing the telescope's primary mirror, Perkin-Elmer Laboratory, May 1979

The mirror and the optical system as a whole were the most important parts of the telescope design, and particularly stringent requirements were placed on them. Typically, telescope mirrors are made to a tolerance of about one-tenth the wavelength of visible light, but since the space telescope was intended to observe from ultraviolet to near-infrared, and the resolution had to be ten times higher than that of ground-based instruments, the manufacturing tolerance its primary mirror was set at 1/20 the wavelength of visible light, or approximately 30 nm.

The Perkin-Elmer company intended to use new computer numerical control machines to produce a mirror of a given shape. Kodak was contracted to manufacture a replacement mirror using traditional polishing methods in case of unforeseen problems with unproven technologies (the Kodak-manufactured mirror is currently on display at the Smithsonian Institution museum). Work on the main mirror began in 1979, using glass with an ultra-low coefficient of thermal expansion. To reduce weight, the mirror consisted of two surfaces - lower and upper, connected by a lattice structure of a honeycomb structure.

Telescope backup mirror, Smithsonian Air and Space Museum, Washington DC

Work on polishing the mirror continued until May 1981, but the original deadlines were missed and the budget was significantly exceeded. NASA reports from the period expressed doubts about the competence of Perkin-Elmer's management and its ability to successfully complete a project of such importance and complexity. To save money, NASA canceled the backup mirror order and moved the launch date to October 1984. The work was finally completed by the end of 1981, after applying a reflective coating of aluminum 75 nm thick and a protective coating of magnesium fluoride 25 nm thick.

Despite this, doubts about Perkin-Elmer's competence remained as the completion date for the remaining components of the optical system was constantly pushed back and the project budget grew. NASA described the company's schedule as "uncertain and changing daily" and delayed the telescope's launch until April 1985. However, the deadlines continued to be missed, the delay grew by an average of one month every quarter, and at the final stage it grew by one day every day. NASA was forced to postpone the launch twice more, first to March and then to September 1986. By that time, the total project budget had grown to $1.175 billion.

Spacecraft

The initial stages of work on the spacecraft, 1980

Another difficult engineering problem was the creation of a carrier apparatus for the telescope and other instruments. The main requirements were protection of the equipment from constant temperature changes during heating from direct sunlight and cooling in the Earth's shadow, and particularly precise orientation of the telescope. The telescope is mounted inside a lightweight aluminum capsule, which is covered with multi-layer thermal insulation, ensuring a stable temperature. The rigidity of the capsule and the fastening of instruments is provided by an internal spatial frame made of carbon fiber.

Although the creation work spacecraft were more successful than the production of the optical system, Lockheed also suffered some delays behind schedule and over budget. By May 1985, cost overruns amounted to about 30% of the original volume, and the lag behind the plan was 3 months. A report prepared by the Marshall Space Center noted that the company did not show initiative in carrying out work, preferring to rely on NASA instructions.

Research coordination and flight control

In 1983, after some confrontation between NASA and the scientific community, the Space Telescope Science Institute was established. The institute is managed by the Universities Association for Astronomical Research ( Association of Universities for Research in Astronomy ) (AURA) and is located on the campus of Johns Hopkins University in Baltimore, Maryland. Hopkins University is one of 32 American universities and foreign organizations members of the association. The Space Telescope Science Institute is responsible for organizing scientific work and providing astronomers with access to the data obtained; NASA wanted to keep these functions under its control, but scientists preferred to transfer them to academic institutions.

The European Space Telescope Coordination Center was founded in 1984 in Garching, Germany, to provide similar facilities to European astronomers.

Flight control was entrusted to the Goddard Space Flight Center, which is located in Greenbelt, Maryland, 48 kilometers from the Space Telescope Science Institute. The functioning of the telescope is monitored round-the-clock in shifts by four groups of specialists. Technical support is provided by NASA and contracting companies through the Goddard Center.

Launch and getting started

Launch of the Discovery shuttle with the Hubble telescope on board

The telescope was originally scheduled to be launched into orbit in October 1986, but on January 28 the Space Shuttle program was suspended for several years, and the launch had to be postponed.

All this time, the telescope was stored in a room with an artificially purified atmosphere, its on-board systems were partially turned on. Storage costs were approximately $6 million per month, which further increased the cost of the project.

The forced delay allowed a number of improvements to be made: solar panels were replaced with more efficient ones, the on-board computer complex and communication systems were modernized, and the design of the aft protective casing was changed in order to facilitate the maintenance of the telescope in orbit. In addition, software to control the telescope was not ready in 1986 and in fact was only finally written at the time of launch in 1990.

After the resumption of shuttle flights in 1988, the launch was finally scheduled for 1990. Before launch, dust accumulated on the mirror was removed using compressed nitrogen, and all systems were thoroughly tested.

Details:

On August 11, 2008, the Hubble orbital telescope completed its 100,000th orbit around globe. The device was launched into low-Earth orbit on April 24, 1990. Over 18 years, with its help, a lot of discoveries were made, many of which became a real revolution in astronomy. And a service mission is planned for October 2008, which should extend the life of the telescope and improve its capabilities.

On May 11, 2009, the space shuttle Atlantis launched from the Cape Canaveral launch site with seven crew members on board. This is the latest mission to repair the damaged Hubble Space Telescope. The Atlantis crew's 11-day flight plan includes five spacewalks to repair Hubble using state-of-the-art scientific instruments specifically designed to repair and improve the telescope, extending its service life at least another until 2014.

In April 2015, the legendary telescope, named after Edwin Hubble (1889-1953), celebrated its twenty-fifth anniversary in Earth orbit.

HUBBLE SPACE TELESCOPE PROJECT

In the twentieth century, astronomers made many strides in studying the universe. These steps would not have been possible without the use of large and complex telescopes located in high-altitude laboratories and controlled big amount qualified specialists. With the launch of the HUBBLE SPACE TELESCOPE (HST), astronomy has made a giant leap forward. Being located outside the earth's atmosphere, HST can record objects and phenomena that cannot be recorded by instruments on the ground.

The HST project was developed by NASA with the participation of the European Space Agency (ESA). This reflecting telescope, 2.4 m (94.5 inches) in diameter, is launched into low (610 kilometers or 330 nautical miles) orbit by the US SPACE SHUTTLE. The project involves periodic maintenance and replacement of equipment on board the telescope. The design life of the telescope is 15 years or more.

INSTITUTE OF SPACE RESEARCH USING TELESCOPE

NASA founded the Space Telescope Science Institute (STScI) to conduct a wide range of global scientific research using the Hubble Telescope. STScI is a large research center where experienced specialists constantly monitor the operation of the telescope. These specialists also help astronomers create observing plans. STScI's mission also includes providing astronomers with the necessary software and technical means for observations.

To make Hubble observations as efficient as possible, STSiC has upgraded its ground-based observing systems. Much of the observation planning process has been automated using intelligent hardware and software. STSiC has cataloged more than 20 million stars to make it easier to find objects to observe, and has also developed a software package to help astronomers process data from the HST. Every day STSiC receives, decrypts, processes and accumulates great amount information received from the HST and also sends it to its clients.

STSiC is affiliated to the Association of Universities for Research in Astronomy ( the Association of Universities for Research in Astronomy, Inc - AURA). The institute itself is located on the Homewood campus of Johns Hopkins University in Baltimore.

WHO USES THE TELESCOPE THEM. HUBBLA?

Unlike other scientific projects, HST is not used exclusively by the individual team that developed the telescope or by a group of astronomers from a single laboratory or institute; in principle, anyone can make an observation using HST.

To conduct observations using HST, an astronomer must send a request to STSiC outlining the scientific justification for the impossibility of making this observation under terrestrial conditions and a description of the proposed observing program. The request is submitted to one of the commissions at STSiC for various sections of astronomy. Each year, these commissions submit ranked lists of observation proposals to the Telescope Research Time Allocation Committee ( Telescope Allocation Committee - TAC). The committee's task is to draft a balanced observing program for the HST. The head of STScI has the final say in approving this program.

At each stage of consideration, the project is assessed according to different criteria. What is the scientific value of the knowledge that will be obtained as a result of research, and how much money and time must be spent for this? Have the limits been reached in the study of this object by ground-based instruments? How likely is the research success? In addition to purely scientific issues, the physical ability of the HST to observe a given object/phenomenon, time and other requirements for the telescope and its resources are also checked.

COMPUTERIZED OBSERVATIONS IN THE SPACE AGE

All observations using the HST must be carefully and precisely planned in advance, since all observations are carried out automatically using computers on board the telescope. After all commands are received on board the HST, the telescope operates in automatic mode, without communication with the Earth. Searching for an object, adjusting instruments, observing itself, etc. are carried out exclusively by on-board computers. Because HST orbits the Earth once every 95 minutes, objects appearing and disappearing too quickly to allow remote control from Earth without losing speed and efficiency of observations. To increase efficiency, observation sessions from different programs alternate with each other. Thus, the vast majority of programs require more than one iteration to complete.

TELESCOPE CAPABILITIES

On board the HST there are: two cameras, two spectrographs, a photometer, and astro sensors. Due to the fact that the telescope is located outside the atmosphere, these instruments allow:

1) Capture images of objects with very high resolution. Ground-based telescopes rarely provide resolution greater than one arcsecond. In all conditions, HST provides a resolution of one-tenth of an arcsecond.
2) Detect low luminosity objects. The largest ground-based telescopes rarely detect objects fainter than magnitude 25. HST can detect objects at magnitude 28, which is almost 20 times smaller.
3) Observe objects in the ultraviolet part of the spectrum. The ultraviolet range makes up the most important part of the spectrum of hot stars, nebulae and other powerful sources of radiation. The Earth's atmosphere absorbs most of the ultraviolet radiation and therefore it is not available for observation (HST can also observe objects in the infrared part of the spectrum, but the sensitivity in this part of the spectrum is still low. With the installation of new instruments a few years after launch, it will increase sharply).
4) Record rapid changes in light intensity, which is impossible under terrestrial conditions due to changes in the transparency of the atmosphere at the time of observations.

DEVICES AND OPTICAL SYSTEMS

The HST has a 94.5-inch (2.4 m) diameter Ritchey-Chrétien mirror on board. Optical sensors detect radiation in the range from 1160 Angstroms (ultraviolet radiation) to 11000 Angstroms (infrared radiation). All observation instruments of the telescope can detect radiation in the ultraviolet range. All instruments except the spectrograph high resolution, can detect radiation in the visible part of the spectrum. The primary instruments on board the telescope cannot detect radiation in the infrared range (although the planetary camera detects radiation in the near-infrared range). All onboard equipment of the telescope receives energy from two solar panels or from batteries (while in the shadow of the Earth).

WHAT THE HUBBLE SPACE TELESCOPE CAN'T CAN

1) HST cannot observe objects and phenomena on Earth, since its object search system and instrument sensitivity are designed only for observing space objects.
2) HST cannot observe the Sun and the illuminated part of the Moon because they are too bright.

Specialists monitoring the implementation of a scientific research program should not make observations that could “blind” the telescope. In the event of computer or human error, when such a threat arises, the HST automatically closes the observation hole with a special door and turns off all observation devices. Using HST you can observe lunar eclipses, observing necessary measures precautions. Eclipses of the Sun by the Earth make it possible to observe Venus, Mercury and other objects with a small angular distance to the Sun within a few minutes. The above restrictions may not be taken into account by the customer when drawing up his draft observation program, because all of them are taken into account automatically by the computer when compiling the overall observation schedule for the HST.

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In April 2015, the legendary telescope, named after Edwin Hubble (1889-1953), celebrated its twenty-fifth anniversary in Earth orbit. No one hides the fact that over the years we had to repeatedly “treat” the device, restore and improve it. However, all the work was not in vain and now even schoolchildren know where the Hubble telescope is located.

This one flies around the entire Earth every ninety minutes at an altitude of about six hundred kilometers above sea level. His main task is to photograph everything that comes into his field of vision. And a lot hits. So, during his work, over 700,000 images were transmitted to Earth. It is difficult to count how many scientific articles and how many discoveries have been made thanks to Hubble!

Space artist

The first successes of the device were not impressive. The pictures came back to Earth blurry and made no impression. This was caused by a defect in the mirror, which, however, was corrected by the astronauts after some time. After the first renovation, several more were carried out. Hubble was improved and equipped with new equipment.

His eye became sharper and sharper. And now, where the famous one is located, there is no more accurate and attentive observer of all the changes that occur in the Universe.

The telescope photographs turn out to be extremely beautiful and artistic. The Universe, as it turned out, has a lot of light and color. In addition, using the shades recorded in the images, scientists were able to identify the chemical substances contained in many formations, newborn stars, and galaxies. There is a giant black hole inside every galaxy, the Universe is constantly accelerating, and we all know this thanks to the Hubble Space Telescope, launched in 1990.

The interesting thing is that we managed to look so far away that the birth of new stars became visible at a distance of 6.5 thousand light years. The process is captured in the smallest detail. The photographs are so original that they will blow anyone's mind.

And in honor of this, a symphony concert was even organized. Thus, a telescope in space has greatly expanded the boundaries of human capabilities and once again made it possible to verify our fragility.

Authors and creators

This unique device was developed by the European Space Agency together with NASA. A total of $6 billion has already been spent on it. Initially, the telescope was supposed to be launched into space 4 years earlier, but the Challenger disaster pushed back this deadline. The program for the creation, launch and further maintenance provided for the repair of the device every 5 years.

However, a damaged mirror, due to which the images were initially unclear, led to the idea that repairs would need to be carried out directly in orbit. And in 1993, the mirror was corrected, the device received additional equipment and began to work even better.

As things stand, considering where the famous Hubble Telescope is located and its impeccable performance, it will last another 5 years, maybe more. Only some kind of catastrophe can disable it. Although a replacement for Hubble is already ready. This is a more accurate and sensitive Webb Space Telescope device.

Space Exploration Assistant

Hubble solved the problem of studying electromagnetic radiation. It registers it in infrared radiation. Ground-based telescopes do this too. However, Hubble turned out to be ten times more effective. Because where the Hubble telescope is located there are more opportunities.

Hubble is a fairly small device, its diameter is just over four meters. Solar panels spread 2 meters wide. But the length is 13 meters. With such seemingly small dimensions, the weight of the device is impressive. The entire telescope, excluding equipment, weighs 11 thousand kilograms, and another 1.5 thousand are instruments.

Maintenance of the telescope falls entirely on the shoulders of the astronauts. Previously planned repairs with descent to Earth could only lead to its damage and deformation. A total of 4 spacewalks were carried out to repair the Hubble.

It is simply impossible to evaluate the work that a telescope has done in space. Thanks to him, we see pictures of Pluto, witnessed the collision of Jupiter with the Shoemaker-Levy comet, and know the age of the Universe itself. According to scientists, its age is close to fourteen billion years. In addition, experts confidently declare the homogeneity of the Universe, the acceleration of processes occurring in it, and much more.

- This is the ancient residence of Chinese emperors, today turned into a huge museum. Nowadays the city is simply called Gugun or Former Palace. This is the largest palace complex in the world.

It's located a little north of the square Tiananmen is considered the main cultural and historical attraction of all. Tourists from all over the world come here every year.

The main palace of the Forbidden City became the residence of the emperor from the moment of its construction, i.e. from the beginning of the 15th century. At that time, the Ming Dynasty reigned. And it ceased to be in 1912, when the last emperor of the Qing dynasty was overthrown.

The palace took about 15 years to build. The best architects, builders, masons, artists and millions of simple unknown builders took part in its construction. Construction was carried out from precious trees and expensive materials.

The emperor lived with his family and servants in the Forbidden City. No one else is at risk death penalty was not allowed here. The palace complex is surrounded by thick walls and a wide moat filled with water.

In total, during the entire period of the empire, 24 emperors of the Ming and Qing dynasties lived in this city. All significant ceremonies were held here; it was the political center of the Great Ming Empire and the Qing Empire.

In 1912, the last emperor of the Qing dynasty, Pu Yi, was overthrown but was allowed to continue living in the Inner Palace. And a museum was organized in the Outer Palace. A few years later, Pu Yi was expelled from his palace.

In the 30s of the last century, when Japan attacked China and captured Beijing, the palace’s jewelry had to be hastily removed. A significant part of them was captured by the Japanese, but out of respect for the former emperor they were preserved.

The Cultural Revolution caused the most damage to this site. In the 50-60s of the 20th century, some artifacts were destroyed here. However, the vandalism was stopped and army battalions were deployed near Gugun to protect the cultural heritage.

For the entire period of its existence before becoming a museum in 1925, Forbidden City has undergone many changes. He was constantly upset and strengthened, huge amounts of money were invested in him.

The entire complex of palaces is an example of Chinese traditional palace architecture. At the end of the 80s of the last century, he was the first in China to enter famous list UNESCO as the largest ancient wooden structure.

Forbidden City today

The Forbidden City is the center of ancient Beijing, which is called Imperial City. Gugun itself is divided into several parts, surrounded by a wall 3.4 km long and almost 8 m high and a moat whose width is more than 50 m.

On three sides there are magnificent imperial gardens and famous parks. To the south of Gugun there is a Sanctuary where all the emperors of China, without exception, worshiped the spirit of the nation and their ancestors.

Also to the south is the Gate of Heavenly Peace with a portrait of the father of the people - Mao Zedong. This gate is the link between ancient Gugong and modern Tiananmen Square.

The entire design of this beautiful architectural masterpiece is filled with symbols of Chinese religion and philosophy, and also emphasizes the greatness of imperial power and its direct connection with heaven. The layout follows ancient traditions.

This palace complex is a real wonder of the world, which is described in books and films. In 1918, he was featured in one of the first Chinese feature films, a biopic about the last emperor Pu Yi, a TV series about Marco Polo, etc.

Modernity

Currently, the Forbidden City is visited by at least 7 million tourists a year, especially in the summer. This is the most famous Chinese landmark. Xi Jinping recently hosted Donald Trump at the Inner Palace.

 

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