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NASA 'Grand Challenge' targets threatening asteroids

Elizabeth Howell, News Writer
Jun 22, 2013, 7:00 UTC

Sen—NASA is taking aim at the large population of space rocks that could threaten Earth. While the agency says we are not in immediate danger of an Armageddon-like scenario, NASA has announced a "Grand Challenge" to widen our knowledge of threatening asteroids.

The announcement may have been timed to bolster NASA's chances of receiving support for a proposed asteroid retrieval mission that, so far, has met with opposition in Congress.

"NASA already is working to find asteroids that might be a threat to our planet, and while we have found 95 percent of the large asteroids near the Earth's orbit, we need to find all those that might be a threat to Earth," stated NASA deputy administrator Lori Garver.

"This grand challenge is focused on detecting and characterizing asteroids and learning how to deal with potential threats. We will also harness public engagement, open innovation and citizen science to help solve this global problem."


The goal is ambitious, and is also very much in its early stages. In concert with the announcement, NASA also announced a request for information (RFI) asking private industry for their proposals for "system concepts and innovative approaches".

NASA's RFI focused on two concepts: finding, moving and exploring an asteroid, and also to search for asteroid threats. Private industry will have until July 18 to respond.

The solicitation focuses on six areas: asteroid observation, asteroid redirection systems, asteroid deflection demonstration, asteroid capture systems, crew systems for asteroid exploration and partnerships/participatory engagement.

At least one space advocacy organization expressed its support for the initative, despite the limited budget that NASA and other government departments are facing in cash-strapped Congress.

NASA Asteroid Mission

One artist's conception of an asteroid retrieval mission proposed by NASA. Credit: NASA/Advanced Concepts Lab

"This directly mirrors the mission of the non-profit private B612 Foundation and our Sentinel mission," stated Ed Lu, the organization's chief executive.

B612's proposal is a telescope (in a "Venus-like orbit" around the Sun) that would probe our Solar System in infrared wavelengths. Its goal is to find 90 percent of asteroids larger than 140 metres nearby Earth, although the foundation added it expects the telescope could find asteroids that are as small as 30 metres.

"There are one million asteroids with the potential to impact Earth with energy large enough to obliterate any major city," Lu added. "We believe that the goal must be to find these one million asteroids -- anything less, in our opinion, would not meet the intent of this Grand Challenge."

The initiative comes at a time when NASA is trying to garner support for an idea to capture an asteroid and bring it closer to Earth. Since the agency introduced that proposal in its fiscal 2014 budget plan, however, representatives in Congress have been cool to the idea.

The current draft NASA authorization bill amended by the U.S. House, Science Space and Technology Committee proposes to remove funding for that idea and also to cut NASA's budget proposal by $1 billion, according to SpaceFlight Now.

Asteroids have received more attention in the popular media this year after the impact of a small asteroid over Chelyabinsk, Russia on February 15. Coincidentally, another space rock was already getting attention from the public: a 50-metre asteroid (2012 DA14) passed harmlessly within 28,000 km of Earth that same day.

Congress ordered NASA in 2005 to seek out 90 percent of asteroids that are a minimum of 140 metres in diameter (enough to destroy a city, experts say) and to compile that list by 2020. 

In 2011, observations with NASA's Wide-field Infrared Survey Explorer showed that the agency has found more than 90 percent of "mid-sized" asteroids (100 metres to 1 kilometre in diameter). There are about 19,500 bodies of this size near Earth, scientists now say; before WISE's observations, astronomers estimated there were closer to 35,000.