Word is leaking out about NASA’s plans to catch an asteroid with a robotic spacecraft and tow it back toward Earth, where it would then be placed in a stable orbit around the Moon. There it can be a nearby destination for NASA’s human exploration program, and serve as an initial facility to help the development of asteroid mining technology.
As U.S. Senator Bill Nelson noted “The plan combines the science of mining an asteroid, along with developing ways to deflect one, along with providing a place to develop ways we can go to Mars.”
While the plan sounds out of far left field, it’s based upon a recent study led by the Keck Institute for Space Studies. The study sought to find ways to retrieve an entire, small asteroid, within reach of NASA’s heritage technology. I participated in this study, along with Planetary Resources’ advisor, veteran astronaut and planetary scientist Dr. Tom Jones.
It is very exciting that NASA is considering this bold step. Our ability to combine human and robotic endeavors, as well as public and private ventures, will ultimately expand our economic sphere of influence into the Solar System. In the words of Dr. Jones, “It’s a great destination for humans to use their talents and skills.” Such a mission would have a variety of roles, from offering a stepping-stone for later human exploration missions to testing techniques for planetary defense.
A 7-meter (23 ft) asteroid may not seem like an impressive target, but the mass of the asteroid is proportional to the cube of its diameter, and it could be as much as 500 tons – roughly equivalent to the mass of the entire International Space Station. It could have as much as 100 tons of water and 200 tons of metals contained within it.
Return of a near-Earth-asteroid of this size would require today’s largest launch vehicles, and today’s most efficient propulsion systems in order to achieve the mission. Even so, capturing and transporting a small asteroid should be a fairly straightforward affair. Mission cost and complexity are likely on par with missions like the Curiosity Mars rover. The greater challenge of such an endeavor may be selecting an asteroid to retrieve.
The Keck study recommended targeting a carbonaceous (C-type) asteroid – one with important volatile resources like water. Carbonaceous asteroids can be very dark – as dark as charcoal. This makes finding them in the black of space more difficult, especially when they are small and reflect very little of the Sun’s light. Furthermore, most asteroids are merely “discovered” for their orbit but not characterized for their “type.”
Determining a mission target requires finding more of these small objects, and ALSO confirming that they are the type of interest. This is precisely why Planetary Resources is deploying our Arkyd-100 space telescopes – not only to detect asteroids, but also to characterize those that are of interest for further prospecting. NASA’s goal will increase our collective knowledge of the asteroid population, for both scientific, planet-protecting and resource-development purposes.
It’s important to mention that a 7-meter carbonaceous asteroid poses no risk to Earth. An asteroid like this would simply burn up in our atmosphere (part of the reason why there are relatively few C-type meteorite samples). As part of the mission, the asteroid would be placed in a stable Lunar orbit, a safe place for long-term access and management. An asteroid in the Earth-Moon system allows for frequent and lower-risk visits by crewed vehicles. With the help of government (or perhaps even commercial) astronauts, technologies to process and extract resources from asteroids could be quickly developed and iterated.
Planetary Resources aims to prospect its own asteroid targets in parallel with NASA’s activity to locate and return an asteroid. Public/private partnerships with NASA would allow for industry to assist in this mission, by identifying, characterizing and helping to select final targets – either through remote sensing, or precursor missions to candidate asteroids. There are certainly many opportunities for innovation to better enable this mission, and to make use of the great resource it will bring near Earth.
What do you think? How can NASA’s new mission protect the planet, further our reach into space, and help open the Solar System for business?