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arXiv · 1303.5774

A Uranian Trojan and the frequency of temporary giant-planet co-orbitals

Mike Alexandersen·Brett Gladman·Sarah Greenstreet·JJ Kavelaars·Jean-Marc Petit·Stephen Gwyn
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Abstract

Trojan objects share a planet's orbit, never straying far from the triangular Lagrangian points, 60 degrees ahead of (L4) or behind (L5) the planet. We report the detection of a Uranian Trojan; in our numerical integrations, 2011 QF99 oscillates around the Uranian L4 Lagrange point for >70 kyr and remains co-orbital for ~1 Myr before becoming a Centaur. We constructed a Centaur model, supplied from the transneptunian region, to estimate temporary co-orbital capture frequency and duration (to factor of two accuracy), finding that at any time 0.4% and 2.8% of the population will be Uranian and Neptunian co-orbitals, respectively. The co-orbital fraction (~2.4%) among Centaurs in the IAU Minor Planet Centre database is thus as expected under transneptunian supply.

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Mike Alexandersen, Brett Gladman, Sarah Greenstreet, JJ Kavelaars, Jean-Marc Petit, Stephen Gwyn. 2013-08-29. A Uranian Trojan and the frequency of temporary giant-planet co-orbitals. https://doi.org/10.1126/science.1238072

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