Gamma-ray Large Space Telescope

GLAST (Gamma-ray Large Area Space Telescope) is a next generation gamma-ray observatory designed to probe for black hole particle jets, gamma-ray bursts, dark matter and other energetic objects and phenomena in the Universe in a range of energies by detecting gamma rays. It will be launched in September 2007.

GLAST will make observations of celestial gamma-ray sources in the energy band extending from 10 keV to more than 300 GeV, the broadest energy coverage ever provided by a single spacecraft for gamma-ray studies. It follows in the footsteps of the Compton Gamma Ray Observatory and the Swift Gamma-Ray Observatory.

The Gamma Ray Large Area Space Telescope is a flagship mission in NASA’s Science Mission Directorate. NASA has teamed up with the U.S. Department of Energy and academic institutions in the United States, France, Germany, Japan, Italy, and Sweden. GLAST will conduct a one-year all sky survey to higher resolution and better sensitivity than previous surveys.

Mission Objectives

GLAST will detect gamma-rays up to hundreds of billions of times more energetic than the light visible to the human eye. These gamma-rays stream out from the hottest objects, most energetic astronomical objects. The observatory should spot gamma-ray burst coming from the edge of the visible Universe. Many of these bursts are thought to signal the violent deaths of enormous stars in supernova explosions.

GLAST will also observe giant black holes. Although black holes are very dark, their gravity makes nearby material swirl towards them and become very hot and bright. Black holes can accelerate jets of particles nearly up to the speed of light. GLAST data may help explain how this happens. GLAST satellite may also reveal exotic new astronomical objects never seen before.

History

* Selected as mission concept in 1994 (Principal Investigator: Peter Michelson, Stanford University)

* Chosen as top priority (with Constellation-X) by Structure and Evolution of the Universe Subcommittee (SEUS)

* Candidate GLAST primary instruments selected for technology development, April 1998.

* GLAST Council meets to give guidance to NASA and DOE on instrument selection process, January 1999.

* Science Requirements Document, drafted by Facility Science Team, signed in July 1999.

* NASA AO issued for primary and secondary instruments: August 1999. Selections: February-March 2000.

*GLAST Mission management assigned to GSFC, 2000

* GLAST approved in July 2001 for the phase B.

*The Large Area Telescope, the satellite’s main instrument built in California was in May 2006 was transported to the US Naval Research Laboratory in Washington DC where it will undergo testing to ensure it will survive the intense vibrations during launch and the extreme temperatures of space.

Info

Launch Mass: 4,277kg (9,429lb)
Orbit: Circular, altitude 550km (340 miles)
Solar Array: Two, 3-panel, deployed, 3-jct GaAs/Ge; 3122 W EOL
Battery: 125 amp-hr NiH2 IPV
Lifetime: The mission is being designed for a lifetime of 5 years, with a goal of 10 years of operations.
Launch Vehicle: Delta 2920H
Instruments:
Used to make observations of gamma-ray sources in the energy band extending from 10 keV to more than 300 GeV.

1. Large Area Telescope: energy range 20Mev to 300GeV.
The primary instrument is the Large Area Telescope (LAT), an imaging gamma-ray telescope employing detectors that convert incoming gamma rays into electrons and their antimatter partners, called positrons. This technique, called pair conversion, enables scientists to track the direction of gamma rays and measure their energy.

2.  Burst Module: energy range 10eV to 30eV.
The secondary instrument is the GLAST Burst Monitor (GBM) that augments the study of gamma-ray bursts. It will detect rays with up to 150 billion times the energy of light detected by the human eye.

Did you know?

* Gamma-ray bursts are the most luminous phenomenon in the known Universe. They remain mysterious. At present the Swift Gamma-Ray Burst Explorer is in operation.

* Traditional telescope mirrors can’t focus gamma-rays like visible light so detectors on GLAST will convert incoming gamma-rays into electrons and their antimatter partners, positrons. Capturing these particles will allow scientists to re-construct the directions of the gamma-rays and measure their energy.

Very High Energy Cosmic Gamma Radiation (Hardcover) by Felix A. Aharonian from Amazon.com, Amazon.co.uk

Gamma-ray Large Area Space Telescope Links

• GLAST Program Data Sheet: from General Dynamics C4 Systems in pdf format.
• General Dynamics C4 Systems
:
• The Gamma Ray Large Area Space Telescope: by Stanford.edu
• The Global Telescope Network: an informal association of scientists, students, individuals and observatories
• Glast User Committee: Info on committee and history in pdf format
• NASA Constellation-X: Official  Home Page
• The Pair Telescope: Info and Picture source.

Goto Space Projects and Info Home Page

Copyright © 2000-2008 Vic Stathopoulos. All rights reserved.
Updated: Saturday 5th, July, 2008