December 20, 2013
NEOWISE Returns To Service After Reactivation
April Flowers for redOrbit.com - Your Universe Online
NASA's Near-Earth Orbit Wide-field Infrared Survey Explorer spacecraft, or NEOWISE for short, made the most comprehensive survey to date of asteroids and comets during its first tour of service. Now, NEOWISE has returned to service, and has sent its first set of test images back to Earth in preparation for a renewed mission.
More than 34,000 asteroids were discovered, and 158,000 were characterized throughout the solar system during NEOWISE's prime mission in 2010 and early 2011. The spacecraft was reactivated in September, following a 31 month hibernation, in order to assist in NASA's efforts to identify the population of potentially hazardous near-Earth objects (NEOs). NASA scientists also expect to use NEOWISE in characterizing previously detected asteroids that could be considered potential targets for future exploration missions.
"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 (JPL). "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 new deep-space images returned by the spacecraft include a previously detected asteroid named (872) Holda. Holda, with a diameter of 26 miles, orbits the sun between Mars and Jupiter in a region astronomers call the asteroid belt. These images allow the research team to compare the quality of the spacecraft's current observations against those of its primary mission.
NEOWISE's 16-inch telescope and infrared cameras are used to seek out and discover unknown NEOs and characterize their size, albedo or reflectivity, and thermal properties. Data collected from asteroids using optical telescopes can be deceiving because asteroids reflect, but do not emit, visible light.
Similar to the cameras aboard NEOWISE, infrared sensors are powerful tools for discovering, cataloging and understanding the asteroid population. The scientists expect that some of the objects that NEOWISE will collect data from will become candidates for NASA's announced asteroid initiative.
The first mission to identify, capture and relocate an asteroid, the initiative represents an unprecedented technological feat that will lead to new scientific discoveries and technological capabilities that will help protect our home planet. To complete President Obama's goal of sending humans to an asteroid by 2025, the initiative brings together the best of NASA's science, technology and human exploration efforts.
"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 in Washington. "NEOWISE is an important element to enhance our ability to support the initiative."
NEOWISE was originally the WISE (Wide-field Infrared Survey Explorer) mission. WISE was launched in December 2009 to scan the entire celestial sky in infrared light—capturing more than 2.7 million images in multiple infrared wavelengths and cataloging more than 747 million objects in space, ranging from galaxies faraway to asteroids and comets much closer to Earth. Most of WISE's electronics were turned off by NASA when it completed its primary mission in February 2011.
The spacecraft was renamed NEOWISE upon reactivation. The new goal is discovering and characterizing asteroids and comets whose orbits approach within 28 million miles (45 million kilometers) from Earth's path around the sun.