[X] Intercept the visiting planetesimal: 56.3%
[X] Collect more dust: 12.5%
[X] Move to a higher orbit: 12.5%
[X] Look around in more detail (The Planetesimal, and ice comets): 6.3%
[X] Collect more gas: 6.3%
[X] Collapse: 6.3%
Concordance: 75.6%
Looking around at the Planetesimal, it indeed seems to be a rather ice-rich visitor from farther up in that lofty domain ice comets languidly hang out in and occasionally descend from. The Planetesimal itself seems less massive than you by about an order of magnitude, but that's not to say absorbing it won't have significant effects. Everyone judges astronomical bodies by their covers, after all.
Going back to ice comets, there's still an incredible abundance of them high up where the weak rays of the young sun aren't quite enough to melt them! You could try grabbing them, or you could just wait for whatever's forming up there to toss down a few.
You adjust your orbit again to arrange a close encounter with the Planetesimal, and you manage a narrow closest approach that sees you tugging at and decelerating it. You manage to nab a lot of its momentum and a fair amount of its unincorporated material pretty close to perihelion with the result that it won't be traveling all the way up to its home any time soon. Of course, this does boost you upward and outward slightly, but given the significant mass difference, it's barely noticeable. Although this isn't quite enough to capture it directly just yet, the Planetesimal is now confined to your neighborhood where another close encounter might be enough to capture it.
Another encounter with the planetesimal seems inevitable, and aside from just focusing on raising or lowering your own orbit, you could make another capture attempt. Doing it carefully will reduce the chance of a miss or a collision and will make future capture attempts easier, but it'll need to be the majority choice. Setting up the capture more hastily, on the other hand, only needs a plurality but virtually guarantees a miss or a violent encounter. Of course, if you're tired of the interloper stealing your lunch, you could always just give it an assist and hope the intersections with your orbit will go away eventually somehow. Unlike attempts at setting up another rendezvous, this would have a synergistic effect with the corresponding option to move into a higher/lower orbit.
[ ] Move to a higher orbit
[ ] Move to a lower orbit
[ ] Attempt to capture the visiting planetesimal...
-[ ] ...boldly!
-[ ] ...carefully
[ ] Fling the visiting planetesimal away...
-[ ] ...into a lower orbit, slightly raising yours
-[ ] ...into a higher orbit, slightly lowering yours
Of course, it could take a while to arrange the encounter, so you may as well do something while waiting too:
[ ] Collect more gas
[ ] Collect more dust
[ ] Collapse
[ ] Look around in more detail (Specify target(s))
(I hope I'm doing the block/category voting thing correctly!
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