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Title: On the Capture of Interstellar Objects by Our Solar System
Abstract

Motivated by recent visits from interstellar comets, along with continuing discoveries of minor bodies in orbit of the Sun, this paper studies the capture of objects on initially hyperbolic orbits by our solar system. Using an ensemble of ∼500 million numerical experiments, this work generalizes previous treatments by calculating the capture cross section as a function of asymptotic speed. The resulting velocity-dependent cross section can then be convolved with any distribution of relative speeds to determine the capture rate for incoming bodies. This convolution is carried out for the usual Maxwellian distribution, as well as the velocity distribution expected for rocky debris ejected from planetary systems. We also construct an analytic description of the capture process that provides an explanation for the functional form of the capture cross section in both the high- and low-velocity limits.

 
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Award ID(s):
2009096
NSF-PAR ID:
10361510
Author(s) / Creator(s):
; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Planetary Science Journal
Volume:
2
Issue:
2
ISSN:
2632-3338
Format(s):
Medium: X Size: Article No. 53
Size(s):
["Article No. 53"]
Sponsoring Org:
National Science Foundation
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