14 DAY TRIAL // Officials with the American space agency have announced recently that they are making progress towards identifying a target space rock for an asteroid-capture mission. Such a flight is currently scheduled to take place around 2025, but it may be conducted as early as 2021. A dozen or so candidates are currently being considered as potential targets.
The overarching goal of the mission is to capture a medium asteroid or a piece of a larger one and inject it into an orbit close to the Moon. This would later enable NASA astronauts to land on the space rock and study it directly. Such a mission could also return much-coveted material samples from the asteroid, potentially allowing geologists a new insight into how the solar system formed.
This goal of landing astronauts on asteroids by 2025 was outlined by US President Barack Obama's National Space Policy. The same document also calls for a manned mission to Mars to be conducted by the early 2030s, which will also include a sample-return segment. Both these objectives have to be achieved with the Space Launch System rocket and the Orion Multipurpose Crew Vehicle capsule.
For the asteroid-capture-centered part of the policy, NASA will use a robotic spacecraft to first trap the asteroid, most likely via some type of inflatable net or bag. The robot would then fire its thrusters to alter the space rock's heading just enough for it to enter the desired orbit. What NASA is currently doing is trying to find the most promising asteroid that requires the least amount of maneuvering.
The two main factors that need to be balanced are mission complexity and the potential scientific return associated with visiting whatever asteroid ends up getting selected. The NASA executive for the Near-Earth Object (NEO) Observations Program, Lindley Johnson, told reporters on March 21 that two different mission concepts are being considered, Space reports.
“For either concept that's being looked at right now – either the capture of a small asteroid less than 10 meters in size, or going after a boulder, large boulder, on a larger asteroid – we have a list of about six or so candidates each,” Johnson said last Friday.
“We continue to look for additional candidates, [as NEO researchers] will continue to do that over the next two to three years, until the time comes to actually determine which will be the best object for the mission,” the official went on to say. The major goal of the NEO program is not to trap asteroids, but to determine which space rocks flying close to Earth may pose a threat to our planet.
One of the most important aspects of the asteroid-capture mission will be the demonstration of multiple new technologies that have been incorporated both on the SLS heavy-lift delivery system and the Orion MPCV capsule design. In effect, this flight would represent a dress rehearsal for a manned mission to Mars.