April 24, 1990 was launched into Earth orbit Hubble orbital telescope, who over almost a quarter of a century of his existence made many great discoveries that shed light on the Universe, its history and secrets. And today we will talk about this orbital observatory, which has become legendary in our time, its history, as well as about some important discoveries made with its help.
History of creation
The idea of placing a telescope where nothing would interfere with its work appeared in the interwar years in the work of the German engineer Hermann Oberth, but the theoretical justification for this was put forward in 1946 by the American astrophysicist Leyman Spitzer. He was so captivated by the idea that he devoted most of his scientific career to its implementation.The first orbital telescope was launched by Great Britain in 1962, and by the United States of America in 1966. The successes of these devices finally convinced the world scientific community of the need to build a large space observatory capable of looking even into the very depths of the Universe.
Work on the project, which eventually became the Hubble Telescope, began in 1970, but for a long time there was not enough funding to successfully implement the idea. There were periods when the American authorities suspended financial flows altogether.
The limbo ended in 1978, when the US Congress allocated $36 million for the creation of the orbital laboratory. At the same time, active work began on the design and construction of the facility, which involved many research centers and technology companies, a total of thirty-two institutions around the world.
Initially, it was planned to launch the telescope into orbit in 1983, then these dates were postponed to 1986. But the disaster of the Challenger space shuttle on January 28, 1986 forced us to once again revise the launch date of the object. As a result, Hubble launched into space on April 24, 1990 on the Discovery shuttle.
Edwin Hubble
Already in the early eighties, the projected telescope was named in honor of Edwin Powell Hubble, the great American astronomer who made a huge contribution to the development of our understanding of what the Universe is, as well as what astronomy and astrophysics of the future should be like.
It was Hubble who proved that there are other galaxies in the Universe besides the Milky Way, and also laid the foundation for the theory of the Expansion of the Universe.
Edwin Hubble died in 1953, but became one of the founders of the American school of astronomy, its most famous representative and symbol. It is not for nothing that not only the telescope, but also the asteroid is named after this great scientist.
The most significant discoveries of the Hubble telescope
In the nineties of the twentieth century, the Hubble telescope became one of the most famous man-made objects mentioned in the press. Photographs taken by this orbital observatory were printed on the front pages and covers of not only scientific and popular science magazines, but also the regular press, including yellow newspapers.
The discoveries made with the help of Hubble significantly revolutionized and expanded the human understanding of the Universe and continue to do so to this day.
The telescope photographed and sent back to Earth more than a million high-resolution images, allowing one to peer into depths of the Universe that would otherwise be impossible to reach.
One of the first reasons for the media to start talking about the Hubble telescope was its photographs of comet Shoemaker-Levy 9, which collided with Jupiter in July 1994. About a year before the fall, while observing this object, the orbital observatory recorded its division into several dozen parts, which then fell over the course of a week onto the surface of the giant planet.
The size of Hubble (mirror diameter is 2.4 meters) allows it to conduct research in a wide variety of areas of astronomy and astrophysics. For example, it was used to take pictures of exoplanets (planets located outside the solar system), observe the agony of old stars and the birth of new ones, find mysterious black holes, explore the history of the Universe, and also test current scientific theories, confirming or refuting them.
Modernization
Despite the launch of other orbital telescopes, Hubble continues to be the main instrument of stargazers of our time, constantly supplying them with new information from the most distant corners of the Universe.However, over time, problems began to arise in the operation of Hubble. For example, already in the first week of operation of the telescope, it turned out that its main mirror had a defect that did not allow achieving the expected sharpness of the images. So we had to install an optical correction system on the object directly in orbit, consisting of two external mirrors.
To repair and modernize the Hubble orbital observatory, four expeditions were carried out to it, during which new equipment was installed on the telescope - cameras, mirrors, solar panels and other devices to improve the operation of the system and expand the scope of the observatory.
Future
After the last upgrade in 2009, it was decided that the Hubble telescope will remain in orbit until 2014, when it will be replaced by a new space observatory, the James Webb. But now it is already known that the operational life of the facility will be extended at least until 2018, or even 2020.The Hubble telescope is probably the most popular and famous object in one way or another connected with space; few people have not heard this name.
Telescope named after the great American scientist Edwin Powell Hubble, whose main achievement was the discovery of the effect of the Expansion of the Universe.
Hubble was launched into Earth orbit in April 1990. At its core, this is not just a telescope - it is a real automatic orbital observatory.
It took an incredible amount of time, resources and financial resources to implement and launch such a complex and large-scale project as Hubble. Apparently, this is why Hubble became a joint project of the two largest space agencies in the world: NASA and ESA(European Space Agency).
Accommodation telescope in space was an absolutely logical step towards its study, since the earth’s atmosphere greatly complicates observation in some ranges (in particular infrared, less so in ultraviolet) and also practically does not allow recording electromagnetic radiation of medium and low intensity. Thus, Hubble takes 7-10 times higher quality images than similar devices on the Earth's surface.
Hubble did not acquire the status of the main “celestial eye” immediately after its launch, because Initially, during the manufacture of optics, in particular the main mirror, the contractors made a serious mistake, which greatly affected the quality of the resulting images. The defect was corrected in 1993 by the first maintenance and repair expedition as a result of the installation of a corrective optical system COSTAR. The installation procedure for this system was one of the most complex operations in the history of astronautics. The result was not long in coming - the quality of images increased by several orders of magnitude and Hubble was ready to conquer new, unknown secrets of space.
a snapshot of the same galaxy before and after installing the COSTAR system
With each of the four subsequent servicing expeditions in 1997, 1999, 2002 and 2009, the space telescope received the latest updates to its technical arsenal, becoming an increasingly sophisticated and versatile tool for exploring the vastness of space. Currently, Hubble has at its disposal the following instruments: wide-angle and planetary cameras, an advanced survey camera, a multi-object near-infrared spectrometer, and an ultraviolet spectrograph. Thanks to its technical arsenal, Hubble has been one way or another involved in the lion's share of space news: discoveries, observations and pictures of the Universe since 1993.
For almost 23 years spent in low-Earth orbit, Hubble has become a legendary telescope. He took several million photographs, made many discoveries, on the basis of which more than one cosmological theory was built. The monthly data flow exceeds 80 Gigabytes, and their total volume has reached 50 Terabytes.
Hubble's most significant observations:
- Filming the collision of Comet Shoemaker-Levy with Jupiter in 1994.
- Detailed images of the surface of Pluto and Eris (another dwarf planet) were obtained.
- Ultraviolet auroras from Saturn, Jupiter and its moon Ganymede were captured.
- Planets have been found outside the solar system, as well as a large number of protoplanetary disks around stars in the Orion Nebula. Evidence has been found that planet formation occurs in many stars in our galaxy.
- Contributed to partial confirmation of the theory about the presence of supermassive black holes in the centers of galaxies.
- Evidence has been obtained that the Universe is expanding at an accelerating rate, rather than at a constant (or decaying) rate.
- The exact age of the Universe has been confirmed - 13.7 billion years.
- The presence of analogues of gamma-ray bursts in the optical range was discovered.
- Confirmation of the hypothesis about the isotropy (i.e. the sameness of the Universe itself and its properties in its individual parts) of the Universe.
- The most distant parts of the Universe were photographed, right up to the time of formation of the first stars (i.e. Hubble allowed us to look into the past 12.7 - 13 billion years).
The merits of the telescope also include a huge number of impressive photographs of the sky and its individual objects, which, in addition to scientific value, also have aesthetic value. Below are the best images from Hubble's 23 years of operation. You can look at and admire these frames for hours.
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 desire for knowledge is ancient in 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 orbiting 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 space 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 delivered 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 the 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 of creating 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 a total 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, lifted 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, Stratoscope-2, equipped with a high-quality Cassegrain system reflector, made its first night flight - 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 sure: if there was an ordinary black hole in 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 Horsehead 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, with 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 has become direct evidence that the Universe arose as a result of the Big Bang and continues to expand rapidly.
The Hubble Telescope, named after the American astronomer Edwin Hubble (1889-1953), was launched into low Earth orbit on April 24, 1990. During its work, more than a million images of stars, planets, galaxies, nebulae and other space objects were obtained.
The Earth's atmosphere is opaque, so if Hubble were located on the surface of our planet, it would see ten times worse.
Immediately after the telescope was launched, it turned out that its main mirror had a defect, which is why the sharpness and resolution of the resulting images were significantly worse than expected. Over the entire history of the telescope, five expeditions to service it took place. The main task of the first flight to Hubble was, of course, to eliminate the mirror defect by installing corrective optics. This was one of the most difficult expeditions in the entire history of our exploration of extraterrestrial space. The astronauts completed five long-duration spacewalks; several cameras, solar panels, guidance systems were replaced... At the end of the work, the orbit was adjusted, since due to friction with the air when moving in the upper layers of the atmosphere, a loss of altitude occurred. The mission was successful and the images obtained after its completion were very good. On subsequent expeditions, planned maintenance work and replacement of equipment with more modern equipment were carried out. For a long time, the fifth flight to Hubble was in doubt.
After the Columbia disaster in March 2003, maintenance work on the telescope was temporarily suspended. NASA decided that every space shuttle should be able to get to the ISS if technical problems arise.
However, the need for maintenance work is clearly overdue. NASA was faced with a serious question: take risks or leave things as they are? The fifth flight to Hubble took place against all odds in the spring of 2009 after a new administrator at NASA. It was decided that this expedition to Hubble would be the last.
How do you get bright and colorful images from Hubble?
Hubble takes pictures of space objects in various ranges from infrared to ultraviolet, the output is black and white photographs of very good quality and resolution. Where do these bright color images come from that first appear on the NASA website and then wander all over the Internet? The answer is quite banal: Photoshop. The photo processing process is complex and time-consuming, don’t be fooled by the two-minute length of the video. This is what it looks like:
The most famous images from Hubble:
Pillars of Creation
The Pillars of Creation or Elephant Trunks are a collection of star dust and gas in the Eagle Nebula (7000 light years from Earth).
Andromeda Galaxy, 2.5 million light years from Earth:
Galaxy M83, 15 million light years from Earth:
The Crab Nebula is the result of a supernova explosion in 1054 AD; in the center of the nebula there is a neutron star (mass of the same order as that of our Sun, size - like a small city).
Galaxy NGC 5194, 23 million light years from Earth:
Bottom left is a supernova that exploded in 1994 on the outskirts of a spiral galaxy.
Sombrero Galaxy, 30 million light years from Earth:
The Omega Nebula in the constellation Sagittarius, 5 thousand light years from Earth:
The best pictures from the Hubble telescope. You can put it on full screen and enjoy:
Illustration copyright BBC World Service Image caption Hubble was launched into orbit by the space shuttle Discovery on April 24, 1990.
This week marks the 25th anniversary of the launch of the Hubble Space Telescope. The Silver Jubilee was marked by another photograph showing young stars shining against a background of a thick cloud of gas and dust.
This star cluster - Westerlund 2 - is located 20 thousand light years from Earth in the constellation Carina.
Illustration copyright BBC World Service Image caption Shortly after the telescope was launched, a defect was discovered in its main mirror, which made all images blurryNASA engineers believe the orbiting telescope will operate for at least another five years.
"The greatest optimist could not have predicted in 1990 the extent to which Hubble would rewrite all of our astrophysics and planetary science textbooks," says NASA Administrator Charlie Bolden.
Shortly after the telescope was launched, a defect was discovered in its main mirror, which made all images blurry.
In 1993, astronauts managed to correct this defect by installing a specially created correction device.
Illustration copyright BBC World Service Image caption Many Hubble images, such as the Eagle Nebula, have become scientific sensationsAfter four more maintenance visits, the telescope is in excellent condition and technically capable of much more than it was immediately after launch.
In the past, Hubble has suffered from gradual deterioration of all six of its gyroscopes, which are used in its attitude control system.
However, after their replacement, only one failed in March 2014. Over the past years, thanks to the replacement of outdated electronic components and the installation of new cameras, the telescope began to work noticeably better.
Illustration copyright BBC World Service Image caption This shot of Jupiter and its moon Ganymede is dramaticIt is difficult to overestimate the contribution of this orbiting telescope to science.
At the time of its launch, astronomers knew nothing about the age of the Universe - estimates ranged from 10 to 20 billion years.
Telescope studies of pulsars have narrowed this spread, and current thinking suggests that 13.8 billion years have passed since the Big Bang.
Illustration copyright BBC World Service Image caption Hubble helped determine the age of the Universe, which, according to current ideas, is 13.8 billion yearsHubble played a critical role in discovering the acceleration at which the Universe is expanding, and also provided decisive evidence for the existence of supermassive black holes at the centers of galaxies.
The strength of the space telescope compared to the new generation of terrestrial telescopes remains its unique ability to penetrate into the deep past of the Universe, observing objects that formed at very early stages of its history.
Illustration copyright BBC World Service Image caption The Crab Nebula is located 6.5 thousand light years away and is the remains of a supernova explosion.Among the telescope's biggest achievements are undoubtedly the "deep field" observations, when it recorded light radiation coming to us from a dark part of the sky for many days and revealed the presence of thousands of extremely distant and very faintly luminous galaxies.
Currently, the telescope spends most of its time making such observations as part of the Frontier Fields program. Hubble looks at six huge clusters of ancient galaxies.
Illustration copyright NASA Image caption Each of the glowing objects in this image represents a distant galaxyUsing the effect of gravitational lensing, Hubble is able to peer into the even more distant past of the Universe.
"Gravity, by bending the light coming from distant galaxies, allows us to look beyond these clusters," says Jennifer Lotz, a participant in the program.
Hubble is currently able to “see” objects whose light is 10-50 times weaker than previously observed ones.
The goal of these studies is to observe the earliest stages of the formation of the first generation of stars and galaxies, distant from the Big Bang by only a few hundred million years.
Illustration copyright BBC World Service Image caption "The Expanding Universe": photographs from the Hubble Telescope, Taschen Publishing HouseThis is exactly what the successor to the Hubble telescope, the much larger and more advanced James Webb Space Telescope, will do on a different level.
Its launch is scheduled for 2018. It was designed and built specifically for this task. Capturing images that take the Hubble telescope days and weeks to capture will only take hours.
