Discovery of a New Retrograde Trans-Neptunian Object: Hint of a Common Orbital Plane for Low Semimajor Axis, High-inclination TNOs and Centaurs
Abstract
Although the majority of Centaurs are thought to have originated in the scattered disk, with the high-inclination members coming from the Oort cloud, the origin of the high-inclination component of trans-Neptunian objects (TNOs) remains uncertain. We report the discovery of a retrograde TNO, which we nickname “Niku,” detected by the Pan-STARRS 1 Outer Solar System Survey. Our numerical integrations show that the orbital dynamics of Niku are very similar to that of 2008 KV42 (Drac), with a half-life of ∼500 Myr. Comparing similar high-inclination TNOs and Centaurs (q > 10 au, a < 100 au, and I > 60°), we find that these objects exhibit a surprising clustering of ascending node, and occupy a common orbital plane. This orbital configuration has high statistical significance: 3.8-σ. An unknown mechanism is required to explain the observed clustering. This discovery may provide a pathway to investigating a possible reservoir of high-inclination objects.
- Publication:
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The Astrophysical Journal
- Pub Date:
- August 2016
- DOI:
- 10.3847/2041-8205/827/2/L24
- arXiv:
- arXiv:1608.01808
- Bibcode:
- 2016ApJ...827L..24C
- Keywords:
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- Kuiper belt: general;
- Oort Cloud;
- surveys;
- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- 18 pages, 4 figures, 1 table, accepted for publication in ApJ Letters