Providing more experience with on-asteroid operations.
If the Rosetta/Philae mission should tell us anything, it’s that there’s still a lot to learn, from an engineering standpoint, about how to operate successfully on the surface of large, low-gravity objects like asteroids or comets. While we’ll continue to get some small-scale experience using other robotic missions, and while a manned mission to a “free-range” asteroid will also provide a good way to get more data, ARM will likely extend our knowledge about how to do operations like these safely with large objects, increasing the likelihood of success of future manned missions to free-range asteroids.
This topic ties back to something that I think some other commentators are missing, and that is there is nothing wrong with practicing at the Moon first for operations that take place in much more remote locations. It is eases the program into risk, while actually stretching boundaries that we haven’t expanded before. There are those that advocate living on the Moon before reaching for Mars, simply because there are a number of unknowns about how to even merely logistically address a Martian mission. I would generally be one of those advocates. The same applies for a post-ARM crewed rendezvous with the delivered asteroidal object – let the robots go far to the regions where higher risks lie, and bring a part of that environment back to us for study at the relatively nearby Moon. We still get the experience of getting to the Asteroids, we still get to stretch ourselves with a Lunar mission with high mission durations, and likely develop a permanent presence in cis-lunar space, all as bonuses to the basic goal of providing a proving ground for asteroid exploration and development. There are enough gremlins in the Earth-Moon system as it is to keep us quite busy, and as Goff points out, there are enough unknows with asteroid rendezvous punctuated by the experience of the Rosetta team. Heading directly to the asteroids isn’t necessary from the point of view of solar system expansion. Setting up an R&D location in the Lunar location is a very valuable idea.*
We have the Mercury-Gemini-Apollo model to fall back on to understand why this is a winning strategy, so why shouldn’t we use it? I see little overtly wrong with heading back to the Moon to stay, or even a dash to Mars, though the latter may be a flag-and-footprints effort as Apollo became, if there isn’t an infrastructure behind it. Pursuing ARM can be implemented to provide that infrastructure.
*I have no problem at all with a direct-to-the-Moon colony, or a sprint to Mars, or sending crews to the asteroids. I think those are ALSO very valuable ideas. Any of those missions are better than the handwringing of politicians in what passes for the so-called “leadership” demonstrated at the current time.