NASA's newly unveiled asteroid-capture plan is still in its early stages, but some details are already emerging about how the audacious mission might work.

President Barack Obama's 2014 federal budget request, which was released Wednesday (April 10), gives NASA $105 million to jump-start a program that would snag an asteroid and park it near the moon. Astronauts would then visit the space rock using the agency's Space Launch System rocket and Orion capsule, perhaps as early as 2021.

"This mission represents an unprecedented technological feat that will lead to new scientific discoveries and technological capabilities and help protect our home planet," NASA chief Charles Bolden said in a statement. [NASA's Asteroid-Capture Mission: How It Works (Images)]

The space agency is still working out how exactly to pull off the mission, which officials are calling the "Asteroid Initiative" or "Asteroid Retrieval and Utilization Mission" at the moment. But a few things are already clear.

For starters, the probe that will chase down and capture the 25-foot (8 meters) or so asteroid will be unmanned. And it will be powered by solar electric propulsion, which generates thrust by accelerating charged particles called ions.

Ion thrusters have been used on other NASA probes, including Dawn, which recently spent a year orbiting the huge asteroid Vesta before departing for the dwarf planet Ceres. But engineers will need to develop an advanced version for the Asteroid Initiative craft, since it will be towing a 500-ton space rock over millions of miles.

"This mission accelerates our technology development activities in high-powered solar electric propulsion," Michael Gazarik, NASA Associate Administrator for Space Technology, said in a statement.

Still, it may take several years for the probe to meet up with the asteroid. The spacecraft will then envelop the space rock with a bag of sorts, as a newvideo animation of NASA's Asteroid Initiative missiondepicts, and de-spin the rock, likely using thrusters.

The asteroid will then be towed to a "stable orbit in the Earth-moon system where astronauts can visit and explore it," NASA officials wrote in a mission description Wednesday.

These visits will be made possible by Orion and the Space Launch System, which are slated to begin flying crews together by 2021. The NASA animation shows astronauts aboard Orion meeting up with the space rock, which the retrieval probe is still holding onto.

See original here:

Inside NASA's Plan to Catch an Asteroid (Bruce Willis Not Required)