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Title: Characterizing the Manx Candidate A/2018 V3
Abstract

Manx objects approach the inner solar system on long-period comet (LPC) orbits with the consequent high inbound velocities, but unlike comets, Manxes display very little to no activity even near perihelion. This suggests that they may have formed in circumstances different from typical LPCs; moreover, this lack of significant activity also renders them difficult to detect at large distances. Thus, analyzing their physical properties can help constrain models of solar system formation as well as sharpen detection methods for those classified as NEOs. Here, we focus on the Manx candidate A/2018 V3 as part of a larger effort to characterize Manxes as a whole. This particular object was observed to be inactive even at its perihelion atq= 1.34 au in 2019 September. Its spectral reflectivity is consistent with typical organic-rich comet surfaces with colors ofgr=0.67±0.02,ri=0.26±0.02, andrz=0.45±0.02, corresponding to a spectral reflectivity slope of 10.6 ± 0.9%/100 nm. A least-squares fit of our constructed light curve to the observational data yields an average nucleus radius of ≈2 km assuming an albedo of 0.04. This is consistent with the value measured from NEOWISE. A surface brightness more » analysis for data taken 2020 July 13 indicated possible low activity (≲0.68 g s−1), but not enough to lift optically significant amounts of dust. Finally, we discuss Manxes as a constraint on solar system dynamical models as well as their implications for planetary defense.

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Authors:
; ; ; ; ; ; ; ; ; ; ; ;
Publication Date:
NSF-PAR ID:
10361774
Journal Name:
The Planetary Science Journal
Volume:
2
Issue:
1
Page Range or eLocation-ID:
Article No. 33
ISSN:
2632-3338
Publisher:
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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