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Reactivated asteroid hunter returns first images

Charles Black, Founder and CEO of Sen
Dec 23, 2013, 8:00 UTC

Sen—NASA's NEOWISE spacecraft (Near-Earth Object Wide-field Infrared Survey Explorer) has taken its first images since being reactivated after more than two and a half years of hibernation.

The probe's mission is to identify the population of potentially hazardous near-Earth objects (NEOs) and to help find candidates for NASA's proposed mission to capture an asteroid and relocate it to a lunar orbit.

NEOWISE began life as the Wide-field Infrared Survey Explorer (WISE) which launched in December 2009 with a primary mission to scan the sky in infrared light. During its primary mission WISE catalogued more than 747 million objects including galaxies, asteroids and comets. Its primary mission ended in February 2011 when the spacecraft was put into hibernation. 

The space probe was woken up in September this year and renamed NEOSWISE for its new mission which will focus on discovering and characterising space rocks orbiting within 28 million miles (45 million km) from Earth's orbit of the Sun. 

"NEOWISE not only gives us a better understanding of the asteroids and comets we study directly, but it will help us refine our concepts and mission operation plans for future, space-based near-Earth object cataloging missions," said Amy Mainzer, principal investigator for NEOWISE at NASA's Jet Propulsion Laboratory.

"The spacecraft is in excellent health, and the new images look just as good as they were before hibernation. Over the next weeks and months we will be gearing up our ground-based data processing and expect to get back into the asteroid hunting business, and acquire our first previously undiscovered space rock, in the next few months."

The main picture shows one of NEOWISE's first images since being reactivated. The dotted red line shows asteroid (872) Holda. With a diameter of 26 miles (42 kilometers), Holda orbits the Sun in the main asteroid belt found between Mars and Jupiter.

Asteroids do not emit visible light, though they do reflect light, so using optical telescopes can give misleading data about an asteroid's size. NEOWISE uses a 16-inch (40-centimeter) telescope and infrared cameras to characterize their size, reflectivity and thermal properties. 

NASA considers NEOWISE to be an important tool to find candidates for its asteroid capture and relocation initiative announced earlier this year. Once relocated to within the Moon's orbit NASA would use its Orion spacecraft to transport four astronauts to land on and explore the space rock. President Obama has set of goal of sending humans on an asteroid by 2025.

"It is important that we accumulate as much of this type of data as possible while the spacecraft remains a viable asset," said Lindley Johnson, NASA's NEOWISE program executive. "NEOWISE is an important element to enhance our ability to support the initiative."

The NEOWISE mission is managed by NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. NASA has released this video of its asteroid mission concept: