NASA Logo, National Aeronautics and Space Administration
NASA Space Science Data Coordinated Archive Header




The Wide-field Infrared Explorer (WIRE) was a two-color, solid hydrogen-cooled, infrared imaging telescope designed to study starburst galaxies and to search for protogalaxies. The science goals of WIRE were to: (1) determine what fraction of the luminosity of the universe at a redshift of >0.5 is due to starburst galaxies; (2) assess how fast and in what ways starburst galaxies evolve; and, (3) examine whether luminous protogalaxies are common at redshifts <3. In order to accomplish these goals, WIRE was to conduct a four month survey at 12 and 25 micrometers over an area of between ten and several hundred square degrees of the sky.

The WIRE telescope itself had an entrace aperture of 30 cm and a 32 x 32 arc-minute field of view. It was of a Ritchey-Chretien design with no moving parts and no reimaging optics.

Shortly after launch, while the spacecraft was still tumbling early after orbit insertion, the telescope cover came off prematurely. This resulted in the exposure of the cryogenic materials to light, warming them at a high rate causing outgassing and increasing the rate of spin of the spacecraft beyond the ability of the reaction wheels to slow it. Although ground controllers began work to decrease the excess spin of the spacecraft, they were not able to do so in time to prevent the total loss of the frozen hydrogen used to cool the primary science instrument. Attempts to recover control of the spacecraft were successful, though as a result of the coolant loss no science data were obtainable.

Alternate Names

  • 25646
  • Explorer 75
  • Small Explorer/WIRE
  • Wide-Field Infrared Explorer

Facts in Brief

Launch Date: 1999-03-05
Launch Vehicle: Pegasus XL
Launch Site: Vandenberg AFB, United States
Mass: 250 kg
Nominal Power: 160 W

Funding Agency

  • NASA-Office of Space Science (United States)


  • Astronomy

Additional Information

Questions and comments about this spacecraft can be directed to: Dr. David T. Leisawitz



NameRoleOriginal AffiliationE-mail
Mr. James G. WatzinProject ManagerNASA Goddard Space Flight
Dr. Samuel H. MoseleyMission ScientistNASA Goddard Space Flight
Mr. Bryan A. FafaulMission ManagerNASA Goddard Space Flight
Mr. Perry HackingMission Principal InvestigatorNASA Jet Propulsion Laboratory
[] NASA Logo -