OSSOS. IV. DISCOVERY OF A DWARF PLANET CANDIDATE IN THE 9:2 RESONANCE WITH NEPTUNE

Journal Article · Thu Dec 01 04:00:00 EST 2016 · The Astronomical Journal (Online)

DOI:https://doi.org/10.3847/0004-6256/152/6/212· OSTI ID:22862828

Bannister, Michele T.; Kavelaars, J. J. ^[1]; Alexandersen, Mike; Chen, Ying-Tung; Lehner, Matthew J. ^[2]; Benecchi, Susan D. ^[3]; Delsanti, Audrey ^[4]; Fraser, Wesley C.; Lacerda, Pedro ^[5]; Gladman, Brett J. ^[6]; Granvik, Mikael ^[7]; Grundy, Will M. ^[8]; Guilbert-Lepoutre, Aurélie ^[9]; Gwyn, Stephen D. J.; Lawler, Samantha ^[10]; Ip, Wing-Huen; Lin, Hsing Wen ^[11]; Jakubik, Marian ^[12]; Jones, R. Lynne ^[13]; Kaib, Nathan ^[14] ; others, and

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1. Department of Physics and Astronomy, University of Victoria, Elliott Building, 3800 Finnerty Road, Victoria, BC V8P 5C2 (Canada)
2. Institute for Astronomy and Astrophysics, Academia Sinica, 11F AS/NTU, National Taiwan University, 1 Roosevelt Road, Sec. 4, Taipei 10617, Taiwan (China)
3. Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719 (United States)
4. Aix Marseille Université, CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326, F-13388, Marseille (France)
5. Astrophysics Research Centre, Queen’s University Belfast, Belfast BT7 1NN (United Kingdom)
6. Department of Physics and Astronomy, University of British Columbia, Vancouver, BC (Canada)
7. Department of Physics, P.O. Box 64, 00014 University of Helsinki (Finland)
8. Lowell Observatory, Flagstaff, AZ (United States)
9. Institut UTINAM UMR6213, CNRS, Univ. Bourgogne Franche-Comté, OSU Theta F-25000 Besançon (France)
10. NRC-Herzberg Astronomy and Astrophysics, National Research Council of Canada, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada)
11. Institute of Astronomy, National Central University, Taiwan (China)
12. Astronomical Institute, Slovak Academy of Science, 05960 Tatranska Lomnica (Slovakia)
13. University of Washington, Washington (United States)
14. HL Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States)

We report the discovery and orbit of a new dwarf planet candidate, 2015 RR{sub 245}, by the Outer Solar System Origins Survey (OSSOS). The orbit of 2015 RR{sub 245} is eccentric (e = 0.586), with a semimajor axis near 82 au, yielding a perihelion distance of 34 au. 2015 RR{sub 245} has g−r=0.59±0.11 and absolute magnitude H{sub r}=3.6±0.1; for an assumed albedo of p {sub V} = 12%, the object has a diameter of ∼670 km. Based on astrometric measurements from OSSOS and Pan-STARRS1, we find that 2015 RR{sub 245} is securely trapped on ten-megayear timescales in the 9:2 mean-motion resonance with Neptune. It is the first trans-Neptunian object (TNO) identified in this resonance. On hundred-megayear timescales, particles in 2015 RR{sub 245}-like orbits depart and sometimes return to the resonance, indicating that 2015 RR{sub 245} likely forms part of the long-lived metastable population of distant TNOs that drift between resonance sticking and actively scattering via gravitational encounters with Neptune. The discovery of a 9:2 TNO stresses the role of resonances in the long-term evolution of objects in the scattering disk and reinforces the view that distant resonances are heavily populated in the current solar system. This object further motivates detailed modeling of the transient sticking population.

• OSTI ID: 22862828
• Journal Information: The Astronomical Journal (Online), Journal Name: The Astronomical Journal (Online) Journal Issue: 6 Vol. 152; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ALBEDO
COMPUTERIZED SIMULATION
DISTANCE
ORBITS
RESONANCE
STAR EVOLUTION
STRESSES