(47171) 1999 TC36, A transneptunian triple |
| |
Authors: | SD Benecchi KS Noll HF Levison |
| |
Institution: | a Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218, USA b Lowell Observatory, 1400 W. Mars Hill Rd., Flagstaff, AZ 86001, USA c Dept. of Space Studies, Southwest Research Institute, 1050 Walnut St. #400, Boulder, CO 80302, USA |
| |
Abstract: | We present new analysis of HST images of (47171) 1999 TC36 that confirm it as a triple system. Fits to the point-spread function (PSF) consistently show that the apparent primary is itself composed of two similar-sized components. The two central components, A1 and A2, can be consistently identified in each of nine epochs spread over 7 years of time. In each instance, the component separation, ranging from 0.023 ± 0.002 to 0.031 ± 0.003 arcsec, is roughly one half of the Hubble Space Telescope’s diffraction limit at 606 nm. The orbit of the central pair has a semi-major axis of a ∼ 867 km with a period of P ∼ 1.9 days. These orbital parameters yield a system mass that is consistent with Msys = 12.75 ± 0.06 × 1018 kg derived from the orbit of the more distant secondary, component B. The diameters of the three components are . The relative sizes of these components are more similar than in any other known multiple in the Solar System. Taken together, the diameters and system mass yield a bulk density of . HST photometry shows that component B is variable with an amplitude of ?0.17 ± 0.05 magnitudes. Components A1 and A2 do not show variability larger than 0.08 ± 0.03 magnitudes approximately consistent with the orientation of the mutual orbit plane and tidally distorted equilibrium shapes. The system has high specific angular momentum of J/J′ = 0.93, comparable to most of the known transneptunian binaries. |
| |
Keywords: | Hubble Space Telescope observations Satellites Composition Kuiper belt Satellites of asteroids Photometry |
本文献已被 ScienceDirect 等数据库收录! |
|