Chandra Space X-ray Observatory (Chandra Space Telescope ) - NASA's space observatory for space exploration in the X-ray range . Launched on July 23, 1999 using the shuttle Columbia . Named after the American physicist and astrophysicist of Indian origin, Subramanyan Chandrasekar , who taught at the University of Chicago from 1937 until his death in 1995 and is known mainly for his work on white dwarfs.
| Chandra X-ray Orbital Observatory | |
|---|---|
 Chandra Observatory | |
| Organization | NASA , Smithsonian Astrophysical Observatory |
| Main contractors | TRW , Northrop Grumman |
| Other names | Advanced X-ray Astrophysics Facility (AXAF) |
| Wave range | X-rays |
| NSSDC ID | 1999-040B |
| Location | Geocentric orbit |
| Orbit type | High apogee orbit |
| Circulation period | 64.2 hours |
| Launch date | July 23, 1999 |
| Launch place | Kennedy Space Center |
| Orbiter | Shuttle Columbia STS-93 |
| Duration | Planned time 5 years |
| Weight | 4790 kg |
| Scientific instruments | |
| CCD X-ray Photometer |
| X-ray diffraction grating |
| High resolution microchannel camera |
| Soft X-ray diffraction grating |
| Site | Chandra X-ray Observatory Center |
Chandra is the third of four Big Observatories launched by NASA in the late XX - early XXI centuries. The first was the Hubble telescope, the second Compton , and the fourth Spitzer .
Content
Development and launch
The observatory was conceived and proposed by NASA in 1976 by Riccardo Giacconi and Harvey Tananbaum as a development of the then-launched HEAO-2 Observatory (Einstein).
In 1992 , due to reduced funding, the design of the observatory was significantly changed - 4 of the 12 planned x-ray mirrors and 2 of the 6 planned focal instruments were removed.
The take-off weight of the AXAF / Chandra was 22,753 kg, which is an absolute record for the mass ever launched into space by space shuttles by shuttles . The bulk of the Chandra complex was a rocket, which allowed the satellite to enter orbit, the apogee of which is about a third of the distance to the moon .
The station was designed for a period of operation equal to 5 years, however, on September 4, 2001, NASA decided to extend its service life by 10 years, thanks to outstanding work results.
In October 2018, the observatory unexpectedly went into safe mode; the main on-board systems were turned off while the solar panels were deployed to maximize energy generation. NASA experts found that problems arose with one of the gyroscopes - for three seconds the on-board systems received incorrect information, as a result of which the computer decided to put the device into safe mode. It was decided to turn off the problem gyroscope, transferring it to the reserve, after which Chandra resumed operation [1] .
Scientific equipment
HRC
The high resolution camera (HRC) has a wide field of view and high angular resolution . The device is a development of a recording detector operating at the HEAO-2 observatory. The angular / spatial resolution of the device is about 0.2 angular seconds, which is slightly better than the image quality created by x-ray mirrors of the observatory (0.3-0.4 angular seconds). An additional advantage of the HRC receiver is its ability to detect a large number of photons per second, which is very important for observing dim objects, such as black holes or neutron stars in our Galaxy.
ACIS
Spectrometers (ACIS, AXAF CCD Imaging Spectrometer) are designed to build images of x-ray objects with simultaneous determination of the energy of each photon. The principle of operation of spectrometers is based on charge-coupled devices ( CCD , CCD). Instruments are the development of CCD photometers developed at the Massachusetts Institute of Technology and first launched at the Japanese observatory ASCA .
LETG / HETG
To solve the problems of high-resolution spectroscopy at the observatory, diffraction gratings are used that deflect x-rays at different angles depending on their energy. Deviated X-rays are then recorded by HRC-S detectors. The high energy resolution achieved with the help of diffraction gratings allows us to study in detail, for example, the properties of the interstellar medium in our and other galaxies.
Discoveries
- The first image of the supernova remnant Cassiopeia A made it possible for astronomers to see a compact object, probably a neutron star or a black hole, at the center of formation.
- In the Crab Nebula, we were able to distinguish between the shock waves around the central pulsar, which until now were invisible to other telescopes.
- It was possible to distinguish the x-ray radiation of a supermassive black hole in the center of the Milky Way .
- Detection of larger volumes of cold gas than previously expected in the center of the Andromeda Nebula .
- A new type of black hole was discovered in the galaxy M82 . Scientists suspect that this is the missing link between the black holes of stellar masses and supermassive black holes.
- High school students using the station discovered a neutron star in the Medusa Nebula .
- Almost all main sequence stars are x-ray sources.
- Updated Hubble Constant .
- Evidence for the existence of dark matter was discovered in 2006 when observing collisions of superclusters of galaxies.
Notes
- ↑ Chandra Space Observatory resumes operation // 3DNews , 10.17.2018
Links
- Wikimedia Commons has media related to Chandra (telescope)
- Official site of the observatory