Data Analysis and Archive for CGRO

The Compton Gamma Ray Observatory (CGRO) was a space observatory detecting light from 20 KeV to 30 GeV in Earth orbit from 1991 to 2000. It featured four main telescopes in one spacecraft covering x-rays and gamma-rays, including various specialized sub-instruments and detectors. Following 14 years of effort, the observatory was launched on the Space ShuttleAtlantis, mission STS-37, on 5 April 1991 and operated until its deorbit on 4 June 2000. It was deployed in low earth orbit at 450 km (280 mi) to avoid the Van Allen radiation belt. It was the heaviest astrophysical payload ever flown at that time at 17,000 kilograms (37,000 lb).

The CGRO was part of NASA's Great Observatories series, with the Hubble Space Telescope, the Chandra X-ray Observatory, and the Spitzer Space Telescope. It was the second of theNASA "Great Observatories" to be launched to space, following the Hubble Space Telescope. CGRO was named after Dr. Arthur Holly Compton (Washington University in St. Louis), Nobel prize winner, for work involved with gamma ray physics. CGRO was built by TRW (now Northrop Grumman Aerospace Systems) in Redondo Beach, CA. CRGO was an international collaboration and additional contributions came from the European Space Agency and various Universities, as well as the U.S. Naval Research Laboratory,

Data Analysis for CGRO

BATSE

• Solar Flare Observations (Solar Data Analysis Center)

COMPTEL

• COMPTEL Exposure Calculator Source Code (tar file)

EGRET

• Introduction to EGRET: Data Products, Analysis and Documentation

Data Archive for CGRO

• CGRO Archive Contents
• CGRO Archive via HEASARC FTP Server
• Search the HEASARC CGRO Archive via HEASARC Browse
• Summary of Reconfigured CGRO Archive

BATSE

• Current GRB Catalog at MSFC
• Reclassification of Trigger Data
• Description of BATSE Data Problems
• FTP Access to BATSE Public Data Archive
• FTP Access to BATSE Software

COMPTEL

• FTP Access to COMPTEL Public Data Archive
• FTP Access to COMPTEL Software and Documentation

EGRET

• FTP Access to EGRET Public Data Archive
• FTP Access to EGRET Software and Documentation
• Third EGRET Catalog
• Third EGRET Catalog ApJ Supplement Paper via ADS
• 1991-1996 EGRET Data on CD
• EGRET TASC Data

OSSE

• OSSE High Level Products
• FTP Access to OSSE Public Data Archive
• FTP Access to OSSE Software

A space observatory The Compton Gamma Ray Observatory (CGRO)

Edited by:
Arip Nurahman
(Teacher and Professional Lecturer)
Guru dan Dosen Profesional
Amin

Compton Gamma Ray Observatory

General information
NSSDC ID	1991-027B
Organization	NASA
Major contractors	TRW
Launch date	5 April 1991
Launched from	Kennedy Space Center
Launch vehicle	Space Shuttle Atlantis STS-37
Mission length	9 years, 2 months
Deorbited	4 June 2000
Mass	17,000 kg (37,000 lb)
Orbit height	450 km (280 mi)
Orbit period	90 min (1.5 h)
Telescope style	Scintillation detectors
Wavelength	Gamma
Diameter	N/A
Collecting area	Varies by instrument
Focal length	N/A
Instruments
BATSE	all-sky monitor
OSSE	pointed detectors
COMPTEL	imaging telescope
EGRET	wide field telescope
Website	NASA Compton Gamma Ray Observatory

Space observatory

A space observatory is any instrument in outer space which is used for observation of distant planets, galaxies, and other outer space objects.A large number of observatories have been launched into orbit, and most of them have greatly enhanced our knowledge of the cosmos.Performing astronomy from the Earth's surface is limited by the filtering and distortion of electromagnetic radiation due to the Earth's atmosphere.

This makes it desirable to place astrononomical observation devices into space.As a telescope orbits the Earth outside the atmosphere it is subject neither to twinkling (distortion due to thermal turbulences of the air) nor to light pollution from artificial light sources on the Earth.

But space-based astronomy is even more important for frequency ranges which are outside of the optic window and the radio window, the only two wavelength ranges of the electromagnetic spectrum that are not severely attenuated by the atmosphere.

For example, X-ray astronomy is nearly impossible when done from the Earth, and has reached its current important stand within astronomy only due to orbiting satellites with X-ray telescopes such as the Chandra observatory or XMM-Newton observatory.

Infrared and ultraviolet are also greatly blocked.

Compton Gamma Ray Observatory

The Compton Gamma Ray Observatory (CGRO) was the second of the NASA "Great Observatories" to be launched to space, following the Hubble Space Telescope.The observatory was launched on the Space Shuttle Atlantis, mission STS-37, on 5 April 1991.It was deployed in low earth orbit at 450 km in order to avoid the Van Allen radiation belt.It was the heaviest astrophysical payload ever flown at that time, at 17000 kg. The CGRO is part of NASA's Great Observatories series, with the Hubble Space Telescope, the Chandra X-ray Observatory, and the Spitzer Space Telescope.

See also

• Fermi Gamma-ray Space Telescope
• Great Observatories program
• Swift Gamma-Ray Burst Mission

References

1. ^ "Gamma-Ray Astronomy in the Compton Era: The Instruments". Gamma-Ray Astronomy in the Compton Era. NASA/ GSFC. http://heasarc.gsfc.nasa.gov/docs/cgro/epo/brochures/compton/bro5.html. Retrieved 2007-12-07.

External links

• NASA Compton Gamma Ray Observatory site
• NASA CGRO images
• New Scientist

Arip Nurahman

Guru dan Dosen Profesional

Semoga Bermanfaat

Compton Gamma Ray Observatory Education

Basic results

• The EGRET instrument conducted the first all sky survey above 100 MeV. Using four years of data it discovered 271 sources, 170 of which were unidentified.
• The COMPTEL instrument completed an all sky map of ²⁶Al (a radioactive isotope of aluminum).
• The OSSE instrument completed the most comprehensive survey of the galactic center, and discovered a possible antimatter "cloud" above the center.
• The BATSE instrument averaged one gamma ray burst event detection per day for a total of approximately 2700 detections. It definitively showed that the majority of gamma-ray bursts must originate in distant galaxies, not nearby in our own Milky Way, and therefore must be enormously energetic.
• The discovery of the first four soft gamma ray repeaters; these sources were relatively weak, mostly below 100 keV and had unpredictable periods of activity and inactivity
• The separation of GRBs into two time profiles: short duration GRBs that last less than 2 seconds, and long duration GRBs that last longer than this.

GRB 990123

Main article: GRB 990123

Gamma ray burst 990123 (23 January 1999) was one of the brightest bursts recorded at the time, and was the first GRB with an optical afterglow observed during the prompt gamma ray emission (a reverse shock flash). This allowed astronomers to measure a redshift of 1.6 and a distance of 3.2 Gpc (10 Gly). Combining the measured energy of the burst in gamma-rays and the distance, the total emitted energy assuming an isotropic explosion could be deduced and resulted in the direct conversion of approximately two solar masses into energy. This finally convinced the community that GRB afterglows resulted from highly collimated explosions, which strongly reduced the needed energy budget.

Miscellaneous results

• The completion of both a pulsar survey and a supernova remnant survey
• The discovery of terrestrial gamma ray sources in 1994 that came from thunderclouds

Education & Outreach

CGRO Overview Discoveries Image Gallery Posters Brochures Displays Viewing the Violent Universe Imagine the Universe! Astronomy Picture of the Day HEASARC Education & Outreach