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Detection of a Satellite of the Trojan Asteroid (3548) Eurybates—A Lucy Mission Target

Noll, K. S. and Brown, M. E. and Weaver, H. A. and Grundy, W. M. and Porter, S. B. and Buie, M. W. and Levison, H. F. and Olkin, C. and Spencer, J. R. and Marchi, S. and Statler, T. S. (2020) Detection of a Satellite of the Trojan Asteroid (3548) Eurybates—A Lucy Mission Target. Planetary Science Journal, 1 (2). Art. No. 44. ISSN 2632-3338. doi:10.3847/psj/abac54.

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We describe the discovery of a satellite of the Trojan asteroid (3548) Eurybates in images obtained with the Hubble Space Telescope. The satellite was detected on three separate epochs, two in 2018 September and one in 2020 January. The satellite has a brightness in all three epochs consistent with an effective diameter of d₂ = 1.2 ± 0.4 km. The projected separation from Eurybates was s ~ 1700–2300 km and varied in position, consistent with a large range of possible orbits. Eurybates is a target of the Lucy Discovery mission and the early detection of a satellite provides an opportunity for a significant expansion of the scientific return from this encounter.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Noll, K. S.0000-0002-6013-9384
Brown, M. E.0000-0002-8255-0545
Weaver, H. A.0000-0003-0951-7762
Grundy, W. M.0000-0002-8296-6540
Porter, S. B.0000-0003-0333-6055
Buie, M. W.0000-0003-0854-745X
Levison, H. F.0000-0001-5847-8099
Olkin, C.0000-0002-5846-716X
Spencer, J. R.0000-0003-4452-8109
Marchi, S.0000-0003-2548-3291
Statler, T. S.0000-0003-4909-9542
Additional Information:© 2020. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Received 2020 June 12; revised 2020 July 17; accepted 2020 August 2; published 2020 September 4. This research is based on observations made with the NASA/ESA Hubble Space Telescope obtained from the Space Telescope Science Institute, which is operated by AURA under NASA contract NAS 5-26555. These observations are associated with programs GO-15144 and GO-16056. Note added in proof. The Eurybates satellite was detected for a fourth time in observations with HST on 2020 July 19 and was not detected in observations obtained on August 3. The data are still insufficient to determine an orbit. Additional observations are planned.
Funding AgencyGrant Number
Subject Keywords:Trojan asteroids ; Natural satellites Solar system
Issue or Number:2
Classification Code:Unified Astronomy Thesaurus concepts: Trojan asteroids (1715); Natural satellites (Solar system) (1089)
Record Number:CaltechAUTHORS:20200911-133133971
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Official Citation:K. S. Noll et al 2020 Planet. Sci. J. 1 44
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:105332
Deposited By: George Porter
Deposited On:15 Sep 2020 20:25
Last Modified:16 Nov 2021 18:42

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