NASA's proposed mission to snag an asteroid and bring it into lunar orbit to be visited by astronauts is beginning to take shape even as arguments over its rationale continue. NASA is asking for $100 million for the mission for FY2014.
According to NasaSpaceFlight.com, the asteroid mission is divided into three parts. They are detection and characterization, rendezvous, capture, and redirection, and finally the expedition to the asteroid by NASA astronauts. The shape of the mission was set forth in a recent presentation to the human exploration and operations committee of the NASA Advisory Council (NAC) by William Gerstenmaier, Associate Administrator for Human Exploration and Operations Mission Directorate.
Detection and characterization
First NASA has to find an asteroid that meets all of its criteria, according to NASASpaceFlight.com. It has to be the right size (about seven meters in diameter according to the original Keck Institute study), the right mass, and the right spin characteristics. The asteroid also has to be already headed toward cislunar space to make it easier to redirect it into lunar orbit. The Keck Institute study suggests that the asteroid be a carbonaceous C-type asteroid containing a mix of volatiles, organic materials, rock, and metal.
Rendezvous, capture, and redirection
Next, a robotic spacecraft, using a 40-kilowatt solar electric propulsion engine, would be sent forth to capture the asteroid and redirect it into a retrograde orbit around the moon, according to NASASpaceFlight.com. The spacecraft would have an inflatable bag or sleeve that would capture the asteroid and a hydrazine system that would help to despin it. Using the continuous thrust possible for an SEP engine, the spacecraft would then deliver it to a lunar orbit that NASA estimates will be stable for a hundred years.
Once the asteroid is safely in lunar orbit, a crew of NASA astronauts, flying in an Orion Multi-Purpose Crew Vehicle launched by the heavy lift Space Launch System, would visit the asteroid in a 20-day mission, NASASpaceFlight.com. The astronauts would use a boom of some sort to connect the Orion with the robotic spacecraft, which would remain attached to the asteroid, and use them to translate from the Orion to the asteroid with several space walks. The astronauts would explore the small asteroid and take samples that would be returned to Earth for study.
NASA: asteroid mission all that can be afforded
According to the Orlando Sentinel, NASA Administrator Charles Bolden ran into some skepticism during a House hearing on the space agency's exploration plans. Why not, the question was posed, go to the moon instead? Bolden replied that considering the meager budgets NASA has been getting, the asteroid mission is all that can be afforded.
The Senate was somewhat more favorable to the asteroid mission with the Space Subcommittee Chair Sen. Bill Nelson, D-Fla., expressing enthusiasm and the usually outspoken ranking member, Sen. Ted Cruz, R-Texas, largely silent.
Mark R. Whittington is the author of Children of Apollo, The Last Moonwalker, and Dreams of Barry's Stepfather. He has written on space subjects for a variety of periodicals, including The Houston Chronicle, The Washington Post, USA Today, the L.A. Times, and The Weekly Standard.
- Space & Astronomy