The “issues” of Monthly Notices of the Royal Astronomical Society (MNRAS) for October are up:
volume 542, #4
–
volume 543, #1
Li, Z. Qiao, D. Li, X. Spatial temporary capture in the Sun–planet three-body system Pgs 625 staf1430
volume 543, #2
Ahuja, G. Aravind, K. Ganesh, S. et al. Long-term monitoring of a dynamically new comet C/2020 V2 (ZTF) Pgs 1178 staf1528
Lund, K. Johansen, A. Agertz, O. The cosmic journey of dust grains – from nucleation to planetary system Pgs 1288 staf1562
Earth certainly captures its share of passing small bodies- we call these “mini-moons” (formally, Temporarily-Captured Objects (TCOs) or Temporarily-Captured Flybys (TCFs)). The general case is a matter of physics and math- time for serious computer crunching! Li et al. specifically use Jupiter as their test case, capturing nearby asteroids and comets. Of note, the authors identify more bodies that might be (temporarily) captured by Jupiter in the future.
The Sun, per se, has a “weakly captured” population, the Oort Cloud. Now here’s C/2020 V2, a dynamically-new comet (perhaps from the Oort Cloud), as it appears to be making its first run through the inner Solar System. These ‘fresh’ comets are of interest both due to their lack of volatile depletion, and because (unlike, say, Halley) they won’t return for eons and this is our only chance. As an aside, the authors point out that their discovery and characterization chain makes a logical stand-in for discovering and characterizing some future target for the Comet Interceptor mission.
Speaking of capture, all stars, star systems, and their members form by eating gas and dust (“accretion”). Gas is a simple matter of physics, but dust is more complicated. Lund et al. hypothesize a life process of dust, mainly using our two known endpoints: astronomical observation of dust in the interstellar medium, and our samples embodied as meteorites. In between, that dust forms asteroids and comets, in turn stars and planets, and oh… everything else. “From dust thou came”, indeed.