29 November 2011 stellar occultation by 2060 Chiron: Symmetric jet-like features
On 29 November 2011 UT, 2060 Chiron occulted a R = 14.9-mag star; data were successfully obtained at the 3-m NASA Infrared Telescope Facility (IRTF) on Mauna Kea and 2-m Las Cumbres Observatory Global Telescope Network (LCOGT) Faulkes Telescope North (FTN) at Haleakala. The MORIS lightcurve shows a solid-body detection of Chiron's nucleus with a chord duration of 16.0±1.4 s, corresponding to a chord length of 158±14 km. Symmetric, dual extinction features in the FTN light curve indicate the presence of optically thick material roughly 300 km from the body midpoint. The duration of the features indicates a 3±2 km feature separated by 10–14 km from a second 7±2 km feature. The symmetry, optical thickness, and narrow size of these features allow for the intriguing possibility of a near-circular arc or shell of material.
© 2015 Elsevier Inc. Received 2 July 2014, Revised 9 January 2015, Accepted 19 January 2015, Available online 4 February 2015. Thanks go to Rick Binzel, Dave Schleicher, Matthew Knight, and an anonymous reviewer for their helpful suggestions and discussion of the results, as well as to the observers A.A.S.G., M.J.P., A.S.B., and A.M.Z, whose efforts made this work possible. A.S.B., M.J.P, and A.A.S.G. were visiting observers at the Infrared Telescope Facility, which is operated by the University of Hawaii under Cooperative Agreement No. NNX-08AE38A with the National Aeronautics and Space Administration, Science Mission Directorate, Planetary Astronomy Program. This work was supported in part by a NASA Planetary Astronomy Grant to MIT (NNX10AB27G). This work was partially supported by the National Research Foundation (NRF) of South Africa. This work makes use of observations from the LCOGT network.