Wide-field Infrared Survey Explorer (WISE) is a NASA infrared-wavelength astronomical space telescope launched in December 2009, and placed in hibernation in February 2011 when its transmitter turned off. It has discovered the first Y Dwarf and Earth trojan asteroid, as well as tens of thousands of new asteroids.
WISE performed an all-sky astronomical survey with images in 3.4, 4.6, 12 and 22 μm wavelength range bands, over ten months using a 40 cm (16 in) diameter infrared telescope in Earth orbit. After its hydrogen coolant depleted, a four-month mission extension called NEOWISE was conducted to search for small solar system bodies close to Earth's orbit (e.g. hazardous comets and asteroids) using its remaining capability.
The All-Sky data including processed images, source catalogs and raw data, was released to the public on March 14, 2012.
Recommissioning
On August 21, 2013, NASA announced it would recommission WISE with a new mission to search for asteroids with orbits that could potentially lead to a collision with Earth. Additionally, it will search for asteroids that a robotic spacecraft could potentially intercept and redirect to orbit the moon. The new mission will begin in September and is scheduled to last three years. With all coolant long used up, NASA plans to bring the temperature of the craft down from its current 200 K to the necessary 75 K by having the telescope stare into deep space for a while. This will cause most of the built up heat to radiate away. The spacecraft's instruments will then be re-calibrated and the new mission will commence.
NASA said it hopes to discover 150 previously unknown target asteroids, known as near-Earth objects. The agency hopes to also learn more about the size and shape of 2,000 known asteroids. It will cost an estimated $5 million per year. The new mission was due in part to calls for NASA to step up asteroid detection after the previously undetected Chelyabinsk meteor exploded over Russia in February 2013.
http://en.wikipedia.org/wiki/Wide-field_Infrared_Survey_Explorer
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