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Possible Signs of Water and Differentiation in a Rocky Exoplanetary Body

Farihi, J. and Brinkworth, C. S. and Gäensicke, B. T. and Marsh, T. R. and Girven, J. and Hoard, D. W. and Klein, B. and Koester, D. (2011) Possible Signs of Water and Differentiation in a Rocky Exoplanetary Body. Astrophysical Journal Letters, 728 (1). Art. No. L8. ISSN 2041-8205.

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Spitzer observations reveal the presence of warm debris from a tidally destroyed rocky and possibly icy planetary body orbiting the white dwarf GD 61. Ultraviolet and optical spectroscopy of the metal-contaminated stellar photosphere reveal traces of hydrogen, oxygen, magnesium, silicon, iron, and calcium. The nominal ratios of these elements indicate an excess of oxygen relative to that expected from rock-forming metal oxides, and thus it is possible that water was accreted together with the terrestrial-like debris. Iron is found to be deficient relative to magnesium and silicon, suggesting the material may have originated as the outer layers of a differentiated parent body, as is widely accepted for the Moon.

Item Type:Article
Related URLs:
URLURL TypeDescription
Farihi, J.0000-0003-1748-602X
Gäensicke, B. T.0000-0002-2761-3005
Marsh, T. R.0000-0002-2498-7589
Hoard, D. W.0000-0002-6800-6519
Additional Information:© 2011 The American Astronomical Society. Received 2010 December 8; accepted 2010 December 30; published 2011 January 18. The authors thank the anonymous referee for a careful reading and a report that improved the manuscript. This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA. This publication makes use of data products from the Two Micron All Sky Survey. Facility: Spitzer (IRAC); Keck:I (HIRES)
Funding AgencyGrant Number
Subject Keywords:circumstellar matter; minor planets, asteroids: general; planetary systems; stars: abundances; white dwarfs
Issue or Number:1
Classification Code:PACS: 97.20.Rp; 97.30.Sw; 98.58.Ay; 97.10.Fy; 97.10.Ex
Record Number:CaltechAUTHORS:20110301-113229371
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Official Citation:J. Farihi et al. 2011 ApJ 728 L8 doi: 10.1088/2041-8205/728/1/L8
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:22586
Deposited By: Ruth Sustaita
Deposited On:03 Mar 2011 16:04
Last Modified:17 Nov 2019 02:01

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