The High Energy Transient Explorer is an American astronomical satellite. The prime objective of HETE is to carry out the first multiwavelength study of gamma-ray bursts with UV, X-ray, and gamma-ray instruments mounted on a single, compact spacecraft. A unique feature of the HETE mission is its capability to localize GRBs with ~10 arc second accuracy in near real time aboard the spacecraft, and to transmit these positions directly to a network of receivers at existing ground-based observatories enabling rapid, sensitive follow-up studies in the radio, IR, and optical bands.

A second HETE satellite, HETE-2, was launched on October 9, 2000 in a followup mission. It was similar to the first HETE, but replaced the UV camera with an additional X-ray camera.