NASA-funded asteroid tracking sensor passes key test
16 April 2013
An infrared sensor that could improve NASA's future detection and tracking of asteroids and comets has passed a critical design test.
The test assessed performance of the Near Earth Object Camera (NEOCam) in an environment that mimicked the temperatures and pressures of deep space. NEOCam is the cornerstone instrument for a proposed new space-based asteroid-hunting telescope.
The sensor could be a vital component to inform plans for the agency's recently announced initiative to develop the first-ever mission to identify, capture and relocate an asteroid closer to Earth for future exploration by astronauts.
Near-Earth objects are asteroids and comets with orbits that come within 28 million miles of Earth's path around the sun. Asteroids do not emit visible light, they reflect it. Depending on how reflective an object is, a small, light-coloured space rock can look the same as a big, dark one. As a result, data collected with optical telescopes using visible light can be deceiving.
"Infrared sensors are a powerful tool for discovering, cataloguising and understanding the asteroid population," said Amy Mainzer, principal investigator for NASA's NEOWISE (Near-Earth Object Wide-Field Infrared Survey Explorer) mission at the agency's Jet Propulsion Laboratory (JPL) in Pasadena, California. "When you observe a space rock with infrared, you are seeing its thermal emissions, which can better define it's size, as well as tell you something about composition."
The NEOCam sensor is designed to be more reliable and significantly lighter in weight for launching aboard space-based telescopes. Once launched, the proposed telescope would be located about four times the distance between Earth and the moon where NEOCam could observe the comings and goings of NEOs every day without the impediments of cloud cover and daylight.
The sensor is the culmination of almost ten years of scientific collaboration between JPL; the University of Rochester, which facilitated the test, and Teledyne Imaging Sensors of Camarillo, California, which developed the sensor.
NASA's NEOWISE is an enhancement of the Wide-field Infrared Survey Explorer, or WISE, mission that launched in December 2009. WISE scanned the entire celestial sky in infrared light twice. It captured more than 2.7 million images of objects in space, ranging from faraway galaxies to asteroids and comets close to Earth. The mission's discoveries of previously unknown objects include 21 comets, more than 34,000 asteroids in the main belt between Mars and Jupiter, and 134 near-NEOs.