Demonstrating planetary defense techniques.
If something similar to ARM Option B is selected, NASA is interested in using it to demonstrate the “gravity tractor” method for deflecting the parent asteroid. Learning how to deflect potentially hazardous asteroids is probably one of the more worthwhile things NASA could be spending money on right now, and providing a way of getting real hands-on experience applying those techniques would be very useful.
This is a big one to me, as it is aligns with one of the major rationale for the existence of the Outbound project. Even as a kid, I generally understood that an asteroid or comet impacting the Earth could ruin your whole day. Or your civilization. Or species. Given that seems that having the whole of humanity living on just Earth was never a good long-term plan. I’ve read my share of science-fiction, and books like Rendezvous with Rama and Lucifer’s Hammer drove the point home in good literary fashion, but real-life events in 1994 made it very clear to me that we are living on borrowed time. Comet Shoemaker-Levy 9 collided with Jupiter that July, with some spectacular results.
That comet, fragmented as it was, left multiple impact marks in the atmosphere of Jupiter, including one that was twice the diameter of the Earth. That is impressive, and frankly intimidating, to contemplate. We are fortunate in the extreme that we have Jupiter and Saturn acting as cosmic shop-vacs, clearing much of the debris of the solar system before it reaches the inner orbits such as ours. However, from impact evidence on Earth, not every object is pulled in by our gas giants. If there are rocks out there lurking around that can blot out the Earth so effectively, I can’t imagine why we’d hesitate in getting off of our home rock and leaving more than one target for the cosmos to aim at.
As noted a few days ago here and elsewhere, ARM Option B is now the mission in play, and if it does anything at all to further our ability to get off-planet or divert inbound species-killer object, that’s outstanding.