A half-billion stars and galaxies from NASA’s WISE mission revealed — many for first time



A new atlas and catalog of the entire infrared sky with more than a half-billion stars, galaxies and other objects captured by NASA\’s Wide-field Infrared Survey Explorer (WISE) mission was unveiled by NASA last week.

\”Today WISE delivers the fruit of 14 years of effort to the astronomical community,\” said Edward L. (Ned) Wright, a UCLA professor of physics and astronomy and the mission’s principal investigator, who began working on the mission in 1998.

A 10-foot unmanned satellite weighing 1,400 pounds, WISE was launched into space on Dec. 14, 2009, and mapped the sky in 2010. Like a powerful set of night-vision goggles, WISE surveyed the cosmos with infrared detectors about 300 times more sensitive than those used in previous survey missions, said Wright, who holds UCLA’s David Saxon Presidential Chair in Physics. WISE collected 15 trillion bytes of data and more than 2.7 million images taken at four infrared wavelengths of light — invisible to the unaided human eye — capturing everything from nearby asteroids to distant galaxies.

The individual WISE exposures have been combined into an atlas of more than 18,000 images and a catalog listing the infrared properties of more than 560 million objects found in the images. Most of the objects are stars and galaxies, with roughly equal numbers of each; many of them have never been seen before.

WISE observations have already led to many discoveries, including elusive failed stars, or Y-dwarfs. Astronomers had been hunting for Y-dwarfs for more than a decade. Because they have been cooling since their formation, they do not shine in visible light and could not be spotted until WISE mapped the sky with its infrared vision. WISE has also found that there are significantly fewer mid-size near-Earth asteroids than astronomers had previously feared. With this data, now more than 90 percent of the largest of the asteroids have been identified.

One image released today shows a surprising view of an \”echo\” of infrared light surrounding an exploded star. The echo was etched in the clouds when a flash of light from the supernova explosion heated surrounding clouds. More discoveries are expected now that astronomers have access to the WISE images.

In another image, moving objects such as asteroids and comets were removed, but residuals of the planets Saturn, Jupiter, and Mars are visible as bright red spots off the plane of the galaxy at the 1 o\’clock, 2 o\’clock and 7 o\’clock positions, respectively.

\”With the release of the all-sky catalog and atlas, WISE joins the pantheon of great sky surveys that have led to so many remarkable discoveries about the universe,\” said Roc Cutri, who leads the WISE data processing and archiving effort at the Infrared and Processing Analysis Center at the California Institute of Technology.