NASA’s Wide-Field Infrared Survey Explorer, or WISE, lifted off Monday morning aboard a Delta 2 rocket from Vandenberg Air Force Base in California.

Like NASA’s Spitzer telescope, WISE will peer out in the infrared. But where Spitzer had a narrow field of view tuned for specific point objects, WISE will conduct wide-field surveys. It will be a major improvement over a previous mission, the Infrared Astronomical Satellite (IRAS), which ended in 1983. The IRAS camera had just 64 pixels in its detectors, whereas WISE has 4 million.

But like both Spitzer and IRAS, WISE will be limited by the coolant it carries to squelch the interfering infrared heat of the spacecraft itself. In 10 months, WISE will make about 1.5 sweeps of the sky before its cryogens run out.

In that time, WISE should pick out hundreds of millions of objects: asteroids, comet debris trails and luminous distant galaxies. It should be particularly adept at finding brown dwarfs and determining their frequency and distribution. These objects, not quite massive enough to ignite the fusion of stars but bigger and hotter than Jupiters, smolder in the infrared. WISE will pick out the coolest of them. The mission could determine not only that brown dwarfs are as common as stars, but it could also spot one lurking closer to the Solar System than Proxima Centauri, a star 4.2 light years away.

Image: NASA/JPL