Multiple origins of asteroid pairs. Issue Volume 10:Issue S318(2015) (1st March 2016)

• Record Type: Journal Article
• Authors: Jacobson, Seth A.
• Editors: Chesley, S. R.; Morbidelli, A.; Jedicke, R.; Farnocchia, D.
• Is Part Of: Proceedings of the International Astronomical Union. Volume 10:Issue S318(2015)
• Page Start: 55
• Page End: 65
• Publication Date: 2016-03-01
• Subjects: minor planets, -- asteroids, -- planets and satellites, -- formation, -- planets and satellites, -- individual (3749 Balam, 8306 Shoko); Astronomy -- Congresses; Astronomy -- Periodicals; 520
• DOI: 10.1017/S1743921315009655
• Languages: English
• ISSNs: 1743-9213

Abstract

Abstract: Rotationally fissioned asteroids produce unbound asteroid pairs that have very similar heliocentric orbits. Backward integration of their current heliocentric orbits provides an age of closest proximity that can be used to date the rotational fission event. Most asteroid pairs follow a predicted theoretical relationship between the primary spin period and the mass ratio of the two pair members that is a direct consequence of the YORP-induced rotational fission hypothesis. If the progenitor asteroid has strength, asteroid pairs may have higher mass ratios or faster rotating primaries. However, the process of secondary fission leaves the originally predicted trend unaltered. We also describe the characteristics of pair members produced by four alternative routes from a rotational fission event to an asteroid pair. Unlike direct formation from the event itself, the age of closest proximity of these pairs cannot generally be used to date the rotational fission event since considerable time may have passed.