WISE completes first all-sky survey

Posted by Emma Woollacott

NASA's Wide-field Infrared Survey Explorer, WISE, completed its first survey of the entire sky over the weekend.

"Like a globe-trotting shutterbug, WISE has completed a world tour with 1.3 million slides covering the whole sky," said Edward Wright, principal investigator of the mission at the University of California, Los Angeles.

To honor the occasion, NASA has processed and stitched together some of these images to create a new image of  the Pleiades cluster of stars, also known as the Seven Sisters.

The picture was taken in February, and shows infrared light from WISE's four detectors in a range of wavelengths. This highlights the dust cloud through which the Seven Sisters and other stars in the cluster are passing.

The WISE all-sky survey is helping us sift through the immense and diverse population of celestial objects," said Hashima Hasan, WISE program scientist at NASA Headquarters in Washington. "It's a great example of the high impact science that's possible from NASA's Explorer Program."

The first release of WISE data, covering about 80 percent of the sky, will be released to astronomers next May.

Since its launch last December, the mission has scanned strips of the sky as it orbited around the Earth's poles. WISE always stays over the Earth's day-night line, and it has taken six months to complete one full scan of the entire sky. It released its first pictures in February.

For the next three months, the mission will map half the sky again to enhance the telescope's data and reveal more hidden asteroids, stars and galaxies. It will give astronomers a look at what's changed in the sky.

The mission will end when the instrument's block of solid hydrogen coolant, needed to chill its infrared detectors, runs out.

"The eyes of WISE have not blinked since launch," said William Irace, the mission's project manager at NASA. "Both our telescope and spacecraft have performed flawlessly and have imaged every corner of our universe, just as we planned."

So far, WISE has observed more than 100,000 asteroids, both known and previously unseen. Most are in the main belt between Mars and Jupiter, but some are near-Earth objects. The infrared telescope has also spotted more than a dozen distant comets.

WISE's infrared vision also allows it to pick up the glow of cool brown dwarfs, as well as distant galaxies.

"WISE is filling in the blanks on the infrared properties of

everything in the universe from nearby asteroids to distant quasars," said Peter Eisenhardt of JPL, project scientist for WISE. "But the most exciting discoveries may well be objects we haven't yet imagined exist."