The NASA/Goddard Space Flight Center (GSFC) Astrophysics Data Facility (ADF) has released a World Wide Web (WWW)-based service to facilitate access to the InfraRed Astronomical Satellite (IRAS) data held in the NSSDC Data Archive and Distribution Service (NDADS) near-line mass storage system. The IRAS mission was completed in 1983, but the data continue to be widely used and are of current interest, for example, in planning observations for the upcoming Infrared Space Observatory (ISO) mission.
IRAS mapped the sky in four infrared bands (12, 25, 60, and 100 microns) with three nearly complete coverages. In addition to the detectors used for the sky survey, the focal plane included a low-resolution infrared (IR) spectrometer, used to obtain spectra of several thousand bright point sources observed in the sky surveys and a two-band IR photometer used to make small maps of selected regions at 50 and 100 microns.
IRAS captured this 1984 image of the Orion Constellation. (NASA press release image number P26296.)
This IRAS allsky image represents the galactic anti-center. (Image processed November 1984. NASA data set image number ZH00189.)
All 23 IRAS data products, ranging from sky survey images to catalogs of point sources, with a total volume of approximately 80 GBs, are accessible through the new ADF/IRAS Web pages. These pages represent a collection of basic documentation about the data products. Two data products, the Point Source Catalog of some 250,000 sources and the IRAS Sky Survey Atlas of images are well known, but several others have not been widely distributed or conveniently accessible before. Among these are the Pointed Observations Catalog of about 7,000 sensitive, non survey-mode maps of selected sources and the Point Source Reject Catalog, which contains candidate sources that failed one or more of the selection tests for inclusion in the Point Source Catalog. For all of the data products the on-line documentation includes descriptions of the formats and citations to the published documentation. The ADF/IRAS pages may be accessed at URL http://bolero.gsfc.nasa.gov/astro/iras/iras_home.html.
A forms-compatible browser is required to identify images of interest and to request data. Those who lack such a browser may follow the instructions provided at URL http://nssdca.gsfc.nasa.gov/ndads/archives_homepage.html. to submit an E-mail request for data from NDADS. User comments and suggestions about the service are solicited, and a feedback form is provided.