SWAS Mission

Collage of SWAS images and Data. Plus a Optical image of the sky showing where the data came from.

SWAS, the Submillimeter Wave Astronomy Satellite, was launched on December 5, 1998 and made observations until July 21, 2004. SWAS measured the amount of water and molecular oxygen in interstellar clouds, and also the amounts of carbon monoxide and atomic carbon, which are believed to be major reservoirs of carbon in these clouds.

SWAS was one of NASA's SmallExplorer Program (SMEX) missions. The overall goal of the mission has beento gain a greater understanding of star formation by determining the compositionof interstellar clouds and establishing the means by which these clouds coolas they collapse to form stars and planets.

SWAS focused on the following spectral lines:

  1. Water (H2O) at 556.936 GHz
  2. Molecular oxygen (O2) at 487.249 GHz
  3. Neutral carbon (CI) at 492.161 GHz
  4. Isotopic carbon monoxide (13CO) at 550.927 GHz
  5. Isotopic water (H218O) at 548.676 GHz

The spacecraft has made detailed 1 degree x 1 degree maps of many giant molecular and dark cloud cores during the first five years of the mission.

In June 2005, the spacecraft was reactivated for a 3 month period (after a year of stand-by operation) in order to observe the effects of the Deep Impact probe's collision with Comet P/Tempel 1.

SWAS made new data public every six months. The final release was made in mid-2005. The on-line data constitutes the tenth SWAS public data release. This consists of a complete set of SWAS data from mission day 0049 (the first day of usable science data) to mission day 2089. 96 sources were observed during this release period, with 40 of them being new sources observed for the first time by SWAS. The previous releases - 5th through 9th are available upon request.

See the Release notes for more details.

SWAS sectral Water signature for the pre-impact Comet 9P-Tempel-1_Impact mission

Collage background image above: Corona Australis Molecular Cloud, Photo by David Malin

A service of the HEASARC and of the Astrophysics Science Division at NASA/GSFC
Goddard Space Flight Center, National Aeronautics and Space Administration
HEASARC Director: Dr. Andrew F. Ptak
LAMBDA Director: Dr. Thomas M. Essinger-Hileman
NASA Official: Dr. Thomas M. Essinger-Hileman
Web Curator: Mr. Michael R. Greason