Close-in satellite detections in the trans-Neptunian region: the special case of Varuna.
Abstract
Photometric techniques can be used to reveal the existence satellites around solar system bodies, but such methods have not been applied to Trans-neptunian objects (TNOs). Specifically, using rotational light-curves it is possible to reveal satellites much closer-in than using the direct imaging technique, and thus helping to remove biases in our current knowledge of the population of binaries in the trans-neptunian region, for which all the known satellites have been detected through high resolution imaging. In this work, we present short-term photometric measurements of the large TNO Varuna in 10 epochs. We have detected changes in the overall shape of the rotational light-curve over shorter time scales that could be due to a close-in satellite whose rotation induces an additional periodicity of 11.9819 h, detected applying the Lomb periodogram technique. Assuming that the satellite is tidally locked we estimate that the satellite orbits Varuna with a period of 11.9819 h, which would imply a distance to the primary of 1300 km, assuming a density of 1100 kg/m^3. This is well outside the Roche limit and too close for direct detection with HST.
- Publication:
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Planets 2020, Ground and Space Observatories: a Joint Venture to Planetary Science
- Pub Date:
- March 2020
- DOI:
- 10.5281/zenodo.4435581
- Bibcode:
- 2020pgso.confE..10F
- Keywords:
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- Zenodo community planets2020