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January 25, 2013

The human eye is finely tuned to see a narrow range of wavelengths — a range of colors from deep red to deep blue. Yet there’s an entire universe beyond those extremes — from wavelengths that are just a thousandth as long as the eye can see, to wavelengths that are a million times longer.

The longer side begins with the infrared. It’s produced by some of the coolest objects in the universe — objects like clouds of gas and dust that are giving birth to new stars. But they’re difficult to study from Earth’s surface because the atmosphere absorbs most infrared energy.

The first major attempt to extend our view into the infrared began 30 years ago today, with the launch of IRAS — the Infrared Astronomy Satellite.

When it was launched, astronomers had discovered about 250,000 objects in the infrared. During its 10 months of operation, IRAS doubled that number. It also provided details on those objects that were impossible to see from the ground — details like temperature and composition. And it provided the most detailed pictures of these objects, allowing us to see their structure.

IRAS studied newborn stars, disks of gas and dust that are giving birth to planets, dusty galaxies, and icy comets. Those observations helped astronomers learn more about how stars and planets are born, and how galaxies evolve — new knowledge made possible by extending our vision into a new realm.


Script by Damond Benningfield, Copyright 2012

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