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High Energy Transient Explorer-1

Phase: Past

Launch Date: November 04, 1996

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Program(s):Astrophysics Explorers, Explorers

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The prime objective of the HETE spacecraft was to carry out the first multiwavelength study of gamma-ray bursts with Ultraviolet, X-ray and gamma ray instruments. A unique feature of the mission was its capability to localize bursts with several arc-second accuracy, in near real-time aboard the spacecraft.

HETE-1 had three instruments: the Omnidirectional Gamma-Ray Spectrometer, the Widefield X-ray Monitor, and the Ultraviolet Transient Camera Array. The Omnidirectional Gamma-Ray Spectrometer consisted of four wide-field gamma-ray detectors with a total effective area of 120 cm**2. It was designed to operate from 6 keV to greater than 1 MeV. The Widefield X-ray Monitor was designed to perform X-ray studies of gamma-ray bursts. The instrument consisted of coded aperture cameras, sensitive in the 2-25 keV energy range, and with location accuracy to ~ 10 arc-minutes or better. The Ultraviolet Transient Camera Array consisted of four ultraviolet CCD cameras operating in the 5 to 7 eV range. It was designed to provide accurate directional information on transient on transient events, and to assist with spacecraft attitude determination.

HETE-1 was launched with the Argentine satellite SAC-B on a Pegasus-XL launch vehicle. Due to a battery failure in the Pegasus XL third stage, HETE-1 was trapped within the Dual Payload Attachment Fitting. HETE-1 lost power several days after launch since it could not deploy its solar panels. HETE-1 and SAC-B deorbited on April 7, 2002.

Last updated: May 28, 2015