A Caltech Library Service

Photometry of Active Centaurs: Colors of Dormant Active Centaur Nuclei

Wong, Ian and Mishra, Aakash and Brown, Michael E. (2019) Photometry of Active Centaurs: Colors of Dormant Active Centaur Nuclei. Astronomical Journal, 157 (6). Art. No. 225. ISSN 1538-3881. doi:10.3847/1538-3881/ab1b22.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Accepted Version
See Usage Policy.

[img] PDF - Erratum
See Usage Policy.


Use this Persistent URL to link to this item:


We present multiband photometric observations of nine Centaurs. Five of the targets are known active Centaurs (167P/CINEOS, 174P/Echeclus, P/2008 CL94, P/2011 S1, and C/2012 Q1), and the other four are inactive Centaurs belonging to the redder of the two known color subpopulations (83982 Crantor, 121725 Aphidas, 250112 2002 KY14, and 281371 2008 FC76). We measure the optical colors of eight targets and carry out a search for cometary activity. In addition to the four inactive Centaurs, three of the five active Centaurs showed no signs of activity at the time of observation, yielding the first published color measurements of the bare nuclei of 167P and P/2008 CL94 without possible coma contamination. Activity was detected on P/2011 S1 and C/2012 Q1, yielding relatively high estimated mass loss rates of 140 ± 20 and 250 ± 40 kg s^(−1), respectively. The colors of the dormant nuclei are consistent with the previously published colors, indicating that any effect of non-geometric scattering from Centaur dust or blanketing debris on the measured colors is minimal. The results of our observations are discussed in the context of the cause of Centaur activity and the color distributions of active and inactive Centaurs. We suggest that the relative paucity of red Centaurs with low-perihelion orbits may not be directly due to the blanketing of the surface by unweathered particulates, but could instead be a result of the higher levels of thermal processing on low-perihelion Centaurs in general.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Wong, Ian0000-0001-9665-8429
Brown, Michael E.0000-0002-8255-0545
Additional Information:© 2019 The American Astronomical Society. Received 2019 March 11; revised 2019 April 17; accepted 2019 April 18; published 2019 May 13. I.W. is supported by a Heising-Simons Foundation 51 Pegasi b postdoctoral fellowship. A.M. thanks the Research Internship in Science and Engineering program organized by Boston University for the summer research opportunity that contributed substantially to this work. This work made use of the JPL Solar System Dynamics high-precision ephemerides through the HORIZONS system.
Errata:Ian Wong et al 2022 AJ 163 142
Funding AgencyGrant Number
Heising-Simons Foundation51 Pegasi b Fellowship
Boston UniversityUNSPECIFIED
Subject Keywords:minor planets, asteroids: general – planets and satellites: surfaces – techniques: photometric
Issue or Number:6
Record Number:CaltechAUTHORS:20190513-111503173
Persistent URL:
Official Citation:Ian Wong et al 2019 AJ 157 225
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:95434
Deposited By: Tony Diaz
Deposited On:13 May 2019 18:28
Last Modified:03 Mar 2022 22:04

Repository Staff Only: item control page