Cryostat
For WISE to function properly, the science instrument needs to avoid having the spacecraft's own heat interfere with the infrared glow given off by the space objects that it's viewing. That chill--as low as 8 Kelvin, or minus 447 degrees Fahrenheit--is achieved through this vacuum-sealed device, the cryostat (which is filled with frozen hydrogen), and now also through the vacuum of space. The coolant is expected to last about nine months before evaporating, NASA says, during which time WISE will have surveyed the sky one-and-a-half times.
Discuss: NASA trains WISE eye on the sky (photos)
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