According to a September 12, 2013 story in Space Daily, NASA scientists have narrowed down the target asteroids for the space agency’s planned first deep space mission to about three. The asteroids would be about ten meters in diameter and presumably would be in orbits that would make them suitable targets.
NASA’s controversial plan involves sending an unmanned spacecraft propelled by ion thrusters to capture and bring into lunar orbit a small asteroid starting about 2019. Then, in the early 2020s, a crewed Orion vehicle would be sent to rendezvous with the asteroid to explore it and take geological samples to return them to Earth.
While the plan would involve the first human expedition beyond low Earth orbit in well over a generation, it is not without its critics. Those who favor an asteroid mission disagree that the plan would fulfill President Obama’s mandate to visit an Earth approaching asteroid, believing that it was understood to involve a deep space expedition to a larger asteroid lasting weeks or months. Advocates of a return to the moon maintain that the entire idea is a waste of time and money. Proponents counter that the scheme is relatively cheap, at just over $2 billion they claim.
NASA will now further characterize the candidate asteroids in the upcoming year.