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Title: A Possible Dynamically Cold Classical Contact Binary: (126719) 2002 CC249
Images of the Kuiper Belt object (126719) 2002CC249 obtained in 2016 and 2017 using the 6.5 m Magellan-Baade Telescope and the 4.3 m Discovery Channel Telescope are presented. A light curve with a periodicity of 11.87±0.01 hr and a peak-to-peak amplitude of 0.79±0.04 mag is reported. This high amplitude double-peaked light curve can be due to a single elongated body, but it is best explained by a contact binary system from its U-/V-shaped light curve. We present a simple full-width-at-half-maximum test that can be used to determine if an object is likely a contact binary or an elongated object based on its light curve. Considering that 2002CC249 is in hydrostatic equilibrium, a system with a mass ratio qmin=0.6, and a density ρmin=1 g cm−3, or less plausible a system with qmax=1, and ρmax=5 g cm−3 can interpret the light curve. Assuming a single Jacobi ellipsoid in hydrostatic equilibrium and an equatorial view, we estimate ρ>0.34 g cm−3, and a/b=2.07. Finally, we report a new color study showing that 2002CC249 displays an ultra red surface characteristic of a dynamically Cold Classical trans-Neptunian object.  more » « less
Award ID(s):
1734484
PAR ID:
10046859
Author(s) / Creator(s):
;
Date Published:
Journal Name:
The Astronomical journal
Volume:
154
Issue:
241
ISSN:
0004-6256
Page Range / eLocation ID:
8pp.
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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