The small satellites of Pluto as observed by New Horizons

H A Weaver; M W Buie; B J Buratti; W M Grundy; T R Lauer; C B Olkin; A H Parker; S B Porter; M R Showalter; J R Spencer; S A Stern; A J Verbiscer; W B McKinnon; J M Moore; S J Robbins; P Schenk; K N Singer; O S Barnouin; A F Cheng; C M Ernst; C M Lisse; D E Jennings; A W Lunsford; D C Reuter; D P Hamilton; D E Kaufmann; K Ennico; L A Young; R A Beyer; R P Binzel; V J Bray; A L Chaikin; J C Cook; D P Cruikshank; C M Dalle Ore; A M Earle; G R Gladstone; C J A Howett; I R Linscott; F Nimmo; J Wm Parker; S Philippe; S Protopapa; H J Reitsema; B Schmitt; T Stryk; M E Summers; C C C Tsang; H H B Throop; O L White; A M Zangari

doi:10.1126/science.aae0030

The small satellites of Pluto as observed by New Horizons

Science. 2016 Mar 18;351(6279):aae0030. doi: 10.1126/science.aae0030.

Authors

H A Weaver¹, M W Buie², B J Buratti³, W M Grundy⁴, T R Lauer⁵, C B Olkin², A H Parker², S B Porter², M R Showalter⁶, J R Spencer², S A Stern², A J Verbiscer⁷, W B McKinnon⁸, J M Moore⁹, S J Robbins², P Schenk¹⁰, K N Singer², O S Barnouin¹¹, A F Cheng¹¹, C M Ernst¹¹, C M Lisse¹¹, D E Jennings¹², A W Lunsford¹², D C Reuter¹², D P Hamilton¹³, D E Kaufmann², K Ennico⁹, L A Young², R A Beyer¹⁴, R P Binzel¹⁵, V J Bray¹⁶, A L Chaikin¹⁷, J C Cook², D P Cruikshank⁹, C M Dalle Ore⁹, A M Earle¹⁶, G R Gladstone¹⁸, C J A Howett², I R Linscott¹⁹, F Nimmo²⁰, J Wm Parker², S Philippe²¹, S Protopapa¹³, H J Reitsema², B Schmitt²¹, T Stryk²², M E Summers²³, C C C Tsang², H H B Throop²⁴, O L White⁹, A M Zangari²

Affiliations

¹ Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA. [email protected].
² Southwest Research Institute, Boulder, CO 80302, USA.
³ NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
⁴ Lowell Observatory, Flagstaff, AZ 86001, USA.
⁵ National Optical Astronomy Observatory, Tucson, AZ 26732, USA.
⁶ SETI Institute, Mountain View, CA 94043, USA.
⁷ Department of Astronomy, University of Virginia, Charlottesville, VA 22904, USA.
⁸ Department of Earth and Planetary Sciences, Washington University, St. Louis, MO 63130, USA.
⁹ Space Science Division, NASA Ames Research Center, Moffett Field, CA 94035, USA.
¹⁰ Lunar and Planetary Institute, Houston, TX 77058, USA.
¹¹ Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
¹² NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
¹³ Department of Astronomy, University of Maryland, College Park, MD 20742, USA.
¹⁴ SETI Institute, Mountain View, CA 94043, USA. Space Science Division, NASA Ames Research Center, Moffett Field, CA 94035, USA.
¹⁵ Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
¹⁶ University of Arizona, Tucson, AZ 85721, USA.
¹⁷ Independent science writer, Arlington, VT, USA.
¹⁸ Southwest Research Institute, San Antonio, TX 78238, USA.
¹⁹ Stanford University, Stanford, CA 94305, USA.
²⁰ University of California, Santa Cruz, CA 95064, USA.
²¹ Université Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France.
²² Roane State Community College, Oak Ridge, TN 37830, USA.
²³ George Mason University, Fairfax, VA 22030, USA.
²⁴ Planetary Science Institute, Tucson, AZ 85719, USA.

PMID: 26989256
DOI: 10.1126/science.aae0030

Abstract

The New Horizons mission has provided resolved measurements of Pluto's moons Styx, Nix, Kerberos, and Hydra. All four are small, with equivalent spherical diameters of ~40 kilometers for Nix and Hydra and ~10 kilometers for Styx and Kerberos. They are also highly elongated, with maximum to minimum axis ratios of ~2. All four moons have high albedos (~50 to 90%) suggestive of a water-ice surface composition. Crater densities on Nix and Hydra imply surface ages of at least 4 billion years. The small moons rotate much faster than synchronous, with rotational poles clustered nearly orthogonal to the common pole directions of Pluto and Charon. These results reinforce the hypothesis that the small moons formed in the aftermath of a collision that produced the Pluto-Charon binary.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.