IRAS - The Infrared Astronomical Satellite


IRAS was launched on January 25, 1983. During its ten months of operation, IRAS scanned more than 96 percent of the sky four times at four infrared bands centered at 12, 25, 60 and 100 microns, increasing the number of cataloged astronomical sources by almost 70%. The IRAS mission has had a major impact on almost every area of astronomy.

GENERAL

Detected about 500,000 infrared sources, doubling the number of cataloged astronomical sources.

SOLAR SYSTEM

Discovered 6 new comets

Found that comets are dustier than previously thought and that dust from comets fills the Solar System

Detected useful infrared data for 2004 asteroids

Detected the zodiacal dust bands - bands of infrared emission that girdle our solar system which are likely to be debris from asteroid collisions

STARS AND STAR FORMATION

Found evidence of zodiacal dust bands around other stars

Discovered a disk of dust grains around the star Vega

Detected disks of material around several other stars.

Detected several probable protostars embedded in clouds of gas and dust

Found that some Bok globules contain protostars

Cataloged thousands of hot, dense cores within clouds of gas and dust which could be newly forming stars

Cataloged over 12,000 variable stars, the largest collection known to date

OUR GALAXY

Revealed for the first time the core of our galaxy

Found infrared cirrus (wisps of warm dust) in almost every direction of space

Data from IRAS was used to show that our galaxy is a barred spiral galaxy - a galaxy which has an elongated central bar-like bulge from which its spiral arms unwind.

GALAXIES

Detected ~75,000 starburst galaxies - galaxies which are extremely bright in the infrared due to intense star formation. It was found that many of these starburst galaxies have "superwinds" emerging from their centers due to the large number of supernova explosions which occur in these galaxies.

Detected strong infrared emission from interacting galaxies

First identified IRAS F10214+4724 - at the time,the most luminous object known in the Universe by a factor of 2. This object may be the best candidate for a forming spiral galaxy yet discovered.