NASA's 'Planetary Defenders' Meeting This Week

Congress held its third hearing earlier this week on the potential threat asteroids pose to Earth. The hearings come in the wake of the asteroid explosion over Chelyabinsk, Russia, last February, which injured about 1,500 people and left the region scrambling to repair damaged buildings.

The Planetary Defense Conference will meet for the week-long Planetary Defense Conference beginning Monday in Flagstaff, Ariz to debate what may be one of the biggest planetary threats civilization faces today.

NASA has not detected any space rocks that pose a threat to civilization any time this century. Nevertheless, there may still be many potentially dangerous Near Earth Objects (NEOs) on a collision course with Earth, according to Ed Lu, a former astronaut, who testified before the House Space, Science, and Technology Committee.

Lu's B612 Foundation, which is trying to raise funds primarily from philanthropists to build a space-based infrared telescope, has announced plans to place the telescope in a special orbit around the Sun to get a better view of NEOs.

"NASA has not even come close to finding and tracking the 1 million smaller asteroids that might only wipe out a city," Lu said. "We can protect the Earth from asteroid impacts, but we can't do it if we don't know where the asteroids are."

NEOCam is the cornerstone instrument for a proposed new space-based asteroid-hunting telescope in the first-ever mission to identify, capture and relocate an asteroid closer to Earth for future exploration by astronauts, according to NASA.

"This sensor represents one of many investments ... in innovative technologies to significantly improve future missions designed to protect Earth from potentially hazardous asteroids," said Lindley Johnson, program executive for NASA's Near-Earth Object Program Office in Washington.

Asteroids do not emit visible light, but reflect it. As a result, data collected with optical telescopes using visible light can be deceiving.

"Infrared sensors are a powerful tool for discovering, cataloging and understanding the asteroid population," said Amy Mainzer, co-author of the research to be published in an upcoming edition of the Journal of Optical Engineering.

"When you observe a space rock with infrared, you are seeing its thermal emissions, which can better define the asteroid's size, as well as tell you something about composition."