View source for Scott S. Sheppard

{{Short description|American astronomer (born 1977)}}
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'''Scott Sander Sheppard''' (born 1977) is an American [[astronomer]] and a discoverer of numerous [[moons]], [[comets]] and [[minor planet]]s in the [[outer Solar System]].<ref name="springer" /><ref name="circ8962" /><ref name="jpl-Satellite-Discovery-Circumstances" />

He is an astronomer in the Department of Terrestrial Magnetism at the [[Carnegie Institution for Science]] in Washington, DC. He attended [[Oberlin College]] as an undergraduate, and received his bachelor in physics with honors in 1998.<ref name="CV" />{{Better source needed|date=August 2021}} Starting as a graduate student at the [[Institute for Astronomy (Hawaii)|Institute for Astronomy]] at the [[University of Hawaiʻi at Mānoa]], he was credited with the discovery of many [[irregular moon|small moons]] of [[Jupiter]], [[Saturn]], [[Uranus]], and [[Neptune]]. He has also discovered the first known trailing [[Neptune trojan]], {{mpl|2008 LC|18}}, the first named leading Neptune trojan, [[385571&nbsp;Otrera]], and the first high inclination Neptune trojan, {{mpl|2005 TN|53}}. These discoveries showed that the Neptune trojan objects are mostly on highly inclined orbits and thus likely captured small bodies from elsewhere in the [[Solar System]].

The [[main-belt]] asteroid [[17898 Scottsheppard]], discovered by [[Lowell Observatory Near-Earth-Object Search|LONEOS]] at [[Anderson Mesa Station]] in 1999, was named in his honor.<ref name="springer" />

==Discoveries==
{{See also|Category:Discoveries by Scott S. Sheppard}}

{| class="wikitable floatright" style="font-size: 90%;"
|-
|+ [[Minor planet]]s discovered: 23<ref name="MPC-Discoverers" />{{needs update|date=November 2022}}
|-
| {{mpl|(79978) 1999 CC|158}} || 15 February 1999 || {{small|{{LoMP|79978|list}}}}{{ref label|codisc|A}}{{ref label|codisc|B}}{{ref label|codisc|C}}
|-
| {{mp|(131695) 2001 XS|254}} || 9 December 2001 || {{small|{{LoMP|131695|list}}}}{{ref label|codisc|B}}{{ref label|codisc|D}}
|-
| {{mpl|(131696) 2001 XT|254}} || 9 December 2001 || {{small|{{LoMP|131696|list}}}}{{ref label|codisc|B}}{{ref label|codisc|D}}
|-
| {{mpl|(131697) 2001 XH|255}} || 11 December 2001 || {{small|{{LoMP|131697|list}}}}{{ref label|codisc|B}}{{ref label|codisc|D}}
|-
| {{mpl|(148975) 2001 XA|255}} || 9 December 2001 || {{small|{{LoMP|148975|list}}}}{{ref label|codisc|B}}{{ref label|codisc|D}}
|-
| {{mp|(168700) 2000 GE|147}} || 2 April 2000 || {{small|{{LoMP|168700|list}}}}{{ref label|codisc|B}}{{ref label|codisc|C}}
|-
| {{mp|(200840) 2001 XN|254}} || 9 December 2001 || {{small|{{LoMP|200840|list}}}}
|-
| [[341520 Mors–Somnus]] || 14 October 2007 || {{small|{{LoMP|341520|list}}}}{{ref label|codisc|C}}
|-
| [[385571 Otrera]] || 16 October 2004 || {{small|{{LoMP|385571|list}}}}{{ref label|codisc|C}}
|-
| [[385695 Clete]] || 8 October 2005 || {{small|{{LoMP|385695|list}}}}{{ref label|codisc|C}}
|-
| {{mp|(469420) 2001 XP|254}} || 10 December 2001 || {{small|{{LoMP|469420|list}}}}{{ref label|codisc|B}}{{ref label|codisc|D}}
|-
| {{mp|(469421) 2001 XD|255}} || 9 December 2001 || {{small|{{LoMP|469421|list}}}}{{ref label|codisc|B}}{{ref label|codisc|D}}
|-
| [[471143 Dziewanna]] || 13 March 2010 || {{small|{{LoMP|471143|list}}}}{{ref label|codisc|C}}{{ref label|codisc|E}}{{ref label|codisc|F}}
|-
| {{mp|(471165) 2010 HE|79}} || 21 April 2010 || {{small|{{LoMP|471165|list}}}}{{ref label|codisc|C}}{{ref label|codisc|E}}{{ref label|codisc|G}}
|-
| {{mp|(471921) 2013 FC|28}} || 17 March 2013 || {{small|{{LoMP|471921|list}}}}{{ref label|codisc|C}}
|-
| {{mp|(508792) 2000 FX|53}} || 31 March 2000 || {{small|{{LoMP|503858|list}}}}{{ref label|codisc|B|}}{{ref label|codisc|C|}}
|-
| {{mp|(523671) 2013 FZ|27}} || 16 March 2013 || {{small|{{LoMP|523671|list}}}}
|-
| {{mp|(523672) 2013 FJ|28}} || 16 March 2013 || {{small|{{LoMP|523672|list}}}}
|-
| {{mp|(523693) 2014 FT|71}} || 24 March 2014 || {{small|{{LoMP|523693|list}}}}
|-
| {{mp|(524365) 2001 XQ|254}} || 10 December 2001 || {{small|{{LoMP|524365|list}}}}{{ref label|codisc|B|}}{{ref label|codisc|D|}}
|-
| {{mp|(524366) 2001 XR|254}} || 10 December 2001 || {{small|{{LoMP|524366|list}}}}{{ref label|codisc|B|}}{{ref label|codisc|D|}}
|-
| [[532037 Chiminigagua]]|| 17 March 2013 || {{small|{{LoMP|532037|list}}}}{{ref label|codisc|C|}}
|-
| {{mp|(532038) 2013 FB|28}} || 17 March 2013 || {{small|{{LoMP|532038|list}}}}{{ref label|codisc|C|}}
|-
| [[541132 Leleākūhonua]] || 13 October 2015 || {{small|{{LoMP|503858|list}}}}{{ref label|codisc|C|}}{{ref label|codisc|H|}}
|-
|{{mpl|2021 PH|27}} || 13 August 2021 || {{MPC|2021+PH27}}
|-
|{{mpl|2022 AP|7}} || 13 January 2022 || {{MPC|2022+AP7}}<ref name="MPEC2022-B21">{{cite web
  |title=MPEC 2022-B21 : 2022 AP7
  |publisher=IAU Minor Planet Center
  |date=2022-01-23
  |url=https://minorplanetcenter.net/mpec/K22/K22B21.html
  |access-date=2022-11-01}}</ref>
|-
| colspan=3 style="font-size: smaller;" |
:{{note label|codisc|A}} with [[Jane X. Luu|J. X. Luu]]
:{{note label|codisc|B}} with [[David C. Jewitt|D. C. Jewitt]]
:{{note label|codisc|C}} with [[Chadwick Trujillo]]
:{{note label|codisc|D}} with [[Jan T. Kleyna|J. T. Kleyna]]
:{{note label|codisc|E}} with [[Andrzej Udalski|A. Udalski]]
:{{note label|codisc|F}} with [[Marcin Kubiak|M. Kubiak]]
:{{note label|codisc|G}} with [[Radosław Poleski|R. Poleski]]
:{{note label|codisc|H}} with [[David J. Tholen|D. J. Tholen]]
|}

Sheppard was the lead discoverer of the object with the most distant orbit known in the Solar System, {{mpl|2012 VP|113}} (nicknamed Biden). In 2014, the similarity of the orbit of {{mp|2012 VP|113}} to other extreme Kuiper belt object orbits led Sheppard and [[Chadwick Trujillo|Trujillo]] to propose that an unknown [[Super-Earth]] mass planet (2–15 Earth masses) in the outermost Solar System beyond 200&nbsp;[[Astronomical Unit|AU]] and up to 1500&nbsp;AU is shepherding these smaller bodies into similar orbits (see [[Planet X]] or [[Planet Nine]]). The extreme trans-Neptunian objects {{mpl|2013 FT|28}} and {{mpl|2014 SR|349}}, announced in 2016 and co-discovered by Sheppard, further show a likely unknown massive planet exists beyond a few hundred AU in the Solar System, with {{mp|2013 FT|28}} being the first known high semi-major axis and high perihelion object anti-aligned with the other known extreme objects. In 2018, the announcement of the high perihelion inner Oort cloud object [[541132 Leleākūhonua]] (nicknamed "The Goblin") by Sheppard et al., being only the third known after {{mp|2012 VP|113}} and Sedna, further demonstrated that a super-Earth planet in the distant Solar System likely exists as Leleākūhonua has many orbital similarities as the two other known inner Oort cloud objects.

===Most notable discoveries===
Sheppard has been involved in the discovery of many [[small Solar System bodies]] such as [[trans-Neptunian object]]s, [[centaur (minor planet)|centaurs]], [[comet]]s and [[near-Earth objects]].
*Three comets are named after him which are [[List of Halley-type comets|Sheppard-Trujillo]] (C/2014 F3), [[List of Halley-type comets|Sheppard-Tholen]] (C/2015 T5) and comet Trujillo-Sheppard (P/2018 V5).
*The [[List of possible dwarf planets|possible dwarf planets]] discovered by Sheppard are [[471143&nbsp;Dziewanna]], {{mpl|2010 KZ|39}}, {{mpl|2010 FX|86}}, [[532037 Chiminigagua]], {{mpl|(523671) 2013 FZ|27}} and {{mpl|2015 KH|162}}.
*In 2018, Sheppard was the lead discoverer of the most distant observed object in the Solar System and first object observed beyond 100 AU, dwarf planet {{mpl|2018 VG|18}} (nicknamed Farout), which is around 120 AU from the Sun.
*He discovered a [[minor-planet moon]] around likely dwarf planet [[532037 Chiminigagua|Chiminigagua]].
*He is also a co-discoverer of a minor-planet moon orbiting the binary trans-Neptunian object [[341520&nbsp;Mors–Somnus]].<ref name="circ8962" />
*Among the numerous [[irregular moon]]s of the major planets in whose discovery he has been involved are:<ref name="jpl-Satellite-Discovery-Circumstances" />

;Jupiter
Discovered [[moons of Jupiter]] ([[Moons of Jupiter#List|full list]]):<ref name="jpl-Satellite-Discovery-Circumstances" />
{{Div col|colwidth=16em}}
*[[Themisto (moon)|Themisto]] (2000), first seen but lost in 1975 by [[Charles T. Kowal|Charles Kowal]]
*[[Harpalyke (moon)|Harpalyke]] (2000)
*[[Praxidike (moon)|Praxidike]] (2000)
*[[Chaldene (moon)|Chaldene]] (2000)
*[[Isonoe (moon)|Isonoe]] (2000)
*[[Erinome (moon)|Erinome]] (2000)
*[[Taygete (moon)|Taygete]] (2000)
*[[Kalyke (moon)|Kalyke]] (2000)
*[[Megaclite (moon)|Megaclite]] (2000)
*[[Iocaste (moon)|Iocaste]] (2000)
*[[Dia (moon)|Dia]] (2000)
*[[Euporie (moon)|Euporie]] (2001)
*[[Orthosie (moon)|Orthosie]] (2001)
*[[Euanthe (moon)|Euanthe]] (2001)
*[[Thyone (moon)|Thyone]] (2001)
*[[Hermippe (moon)|Hermippe]] (2001)
*[[Pasithee (moon)|Pasithee]] (2001)
*[[Aitne (moon)|Aitne]] (2001)
*[[Eurydome (moon)|Eurydome]] (2001)
*[[Autonoe (moon)|Autonoe]] (2001)
*[[Sponde (moon)|Sponde]] (2001)
*[[Kale (moon)|Kale]] (2001)
*[[Arche (moon)|Arche]] (2002)
*[[Eukelade (moon)|Eukelade]] (2003)
*[[Helike (moon)|Helike]] (2003)
*[[Aoede (moon)|Aoede]] (2003)
*[[Hegemone (moon)|Hegemone]] (2003)
*[[Kallichore (moon)|Kallichore]] (2003)
*[[Cyllene (moon)|Cyllene]] (2003)
*[[Mneme (moon)|Mneme]] (2003)
*[[Thelxinoe (moon)|Thelxinoe]] (2003)
*[[Carpo (moon)|Carpo]] (2003)
*[[Kore (moon)|Kore]] (2003)
*[[Herse (moon)|Herse]] (2003)
*[[S/2003 J 2]] (2003)
*[[Eupheme (moon)|Eupheme]] (2003)
*[[S/2003 J 4]] (2003)
*[[Eirene (moon)|Eirene]] (2003)
*[[S/2003 J 9]] (2003)
*[[S/2003 J 10]] (2003)
*[[S/2003 J 12]] (2003)
*[[Philophrosyne (moon)|Philophrosyne]] (2003)
*[[S/2003 J 16]] (2003)
*[[Jupiter LV]] (2003)
*[[Jupiter LXI]] (2003)
*[[S/2003 J 23]] (2003)
*[[S/2003 J 24]] (2003)
*[[Jupiter LXXII]] (2011)
*[[Jupiter LVI]] (2011)
*[[S/2011 J 3]] (2011)
*[[Jupiter LIV]] (2016)
*[[Valetudo (moon)|Valetudo]] (2016)
*[[S/2016 J 3]] (2016)
*[[S/2016 J 4]] (2016)
*[[Jupiter LIX]] (2017)
*[[Jupiter LXIII]] (2017)
*[[Jupiter LXIV]] (2017)
*[[Pandia (moon)|Pandia]] (2017)
*[[Jupiter LXVI]] (2017)
*[[Jupiter LXVII]] (2017)
*[[Jupiter LXVIII]] (2017)
*[[Jupiter LXIX]] (2017)
*[[Jupiter LXX]] (2017)
*[[S/2017 J 10]] (2017)
*[[S/2017 J 11]] (2017)
*[[Ersa (moon)|Ersa]] (2018)
*[[S/2018 J 2]] (2018)
*[[S/2018 J 3]] (2018)
*[[S/2018 J 4]] (2018)
*[[S/2021 J 1]] (2021)
*[[S/2021 J 2]] (2021)
*[[S/2021 J 3]] (2021)
*[[S/2021 J 4]] (2021)
*[[S/2021 J 5]] (2021)
*[[S/2021 J 6]] (2021)
*[[S/2022 J 1]] (2022)
*[[S/2022 J 2]] (2022)
*[[S/2022 J 3]] (2022)
{{Div col end}}

;Saturn
Discovered [[moons of Saturn]] ([[Moons of Saturn#List|full list]]):<ref name="jpl-Satellite-Discovery-Circumstances" />
{{Div col|colwidth=16em}}
*[[Narvi (moon)|Narvi]] (2003)
*[[Fornjot (moon)|Fornjot]] (2004)
*[[Farbauti (moon)|Farbauti]] (2004)
*[[Aegir (moon)|Aegir]] (2004)
*[[Bebhionn (moon)|Bebhionn]] (2004)
*[[Hati (moon)|Hati]] (2004)
*[[Bergelmir (moon)|Bergelmir]] (2004)
*[[Fenrir (moon)|Fenrir]] (2004)
*[[Bestla (moon)|Bestla]] (2004)
*[[S/2004 S 7]] (2004)
*[[S/2004 S 12]] (2004)
*[[S/2004 S 13]] (2004)
*[[S/2004 S 17]] (2004)
*[[Hyrrokkin (moon)|Hyrrokkin]] (2004)
*[[Gridr (moon)|Gridr]] (2004)
*[[S/2004 S 21]] (2004)
*[[Angrboda (moon)|Angrboda]] (2004)
*[[Skrymir (moon)|Skrymir]] (2004)
*[[S/2004 S 24]] (2004)
*[[Gerd (moon)|Gerd]] (2004)
*[[Saturn LVIII]] (2004)
*[[Eggther (moon)|Eggther]] (2004)
*[[S/2004 S 28]] (2004)
*[[Saturn LX]] (2004)
*[[Beli (moon)|Beli]] (2004)
*[[S/2004 S 31]] (2004)
*[[Gunnlod (moon)|Gunnlod]] (2004)
*[[Thiazzi (moon)|Thiazzi]] (2004)
*[[Saturn LXIV]] (2004)
*[[Alvaldi (moon)|Alvaldi]] (2004)
*[[S/2004 S 36]] (2004)
*[[S/2004 S 37]] (2004)
*[[Geirrod (moon)|Geirrod]] (2004)
*[[S/2004 S 39]] (2004)
*[[S/2004 S 40]] (2004)
*[[S/2004 S 41]] (2004)
*[[S/2004 S 42]] (2004)
*[[S/2004 S 43]] (2004)
*[[S/2004 S 44]] (2004)
*[[S/2004 S 45]] (2004)
*[[S/2004 S 46]] (2004)
*[[S/2004 S 47]] (2004)
*[[S/2004 S 48]] (2004)
*[[S/2004 S 49]] (2004)
*[[S/2004 S 50]] (2004)
*[[S/2004 S 51]] (2004)
*[[S/2004 S 52]] (2004)
*[[S/2004 S 53]] (2004)
*[[S/2004 S 54]] (2004)
*[[S/2004 S 55]] (2004)
*[[S/2004 S 56]] (2004)
*[[S/2004 S 57]] (2004)
*[[S/2004 S 58]] (2004)
*[[S/2004 S 59]] (2004)
*[[S/2004 S 60]] (2004)
*[[S/2004 S 61]] (2004)
*[[S/2005 S 4]] (2005)
*[[S/2005 S 5]] (2005)
*[[S/2005 S 6]] (2005)
*[[S/2005 S 7]] (2005)
*[[Kari (moon)|Kari]] (2006)
*[[Loge (moon)|Loge]] (2006)
*[[Surtur (moon)|Surtur]] (2006)
*[[Skoll (moon)|Skoll]] (2006)
*[[Greip (moon)|Greip]] (2006)
*[[Jarnsaxa (moon)|Jarnsaxa]] (2006)
*[[S/2006 S 1]] (2006)
*[[S/2006 S 3]] (2006)
*[[S/2006 S 9]] (2006)
*[[S/2006 S 10]] (2006)
*[[S/2006 S 11]] (2006)
*[[S/2006 S 12]] (2006)
*[[S/2006 S 13]] (2006)
*[[S/2006 S 14]] (2006)
*[[S/2006 S 15]] (2006)
*[[S/2006 S 16]] (2006)
*[[S/2006 S 17]] (2006)
*[[S/2006 S 18]] (2006)
*[[S/2006 S 19]] (2006)
*[[S/2006 S 20]] (2006)
*[[S/2006 S 21]] (2006)
*[[S/2006 S 22]] (2006)
*[[S/2006 S 23]] (2006)
*[[S/2006 S 24]] (2006)
*[[S/2006 S 25]] (2006)
*[[S/2006 S 26]] (2006)
*[[S/2006 S 27]] (2006)
*[[S/2006 S 28]] (2006)
*[[S/2006 S 29]] (2006)
*[[Tarqeq]] (2007)
*[[S/2007 S 2]] (2007)
*[[S/2007 S 3]] (2007)
*[[S/2007 S 5]] (2007)
*[[S/2007 S 6]] (2007)
*[[S/2007 S 7]] (2007)
*[[S/2007 S 8]] (2007)
*[[S/2007 S 9]] (2007)
*[[S/2007 S 10]] (2007)
*[[S/2007 S 11]] (2007)
*[[S/2019 S 3]] (2019)
*[[S/2019 S 9]] (2019)
*[[S/2019 S 11]] (2019)
*[[S/2019 S 17]] (2019)
*[[S/2019 S 18]] (2019)
*[[S/2019 S 21]] (2019)
*[[S/2019 S 24]] (2019)
*[[S/2019 S 25]] (2019)
*[[S/2019 S 27]] (2019)
*[[S/2019 S 29]] (2019)
*[[S/2019 S 31]] (2019)
*[[S/2019 S 33]] (2019)
*[[S/2019 S 34]] (2019)
*[[S/2019 S 40]] (2019)
*[[S/2019 S 42]] (2019)
*[[S/2019 S 43]] (2019)
*[[S/2020 S 1]] (2020)
*[[S/2020 S 8]] (2020)
*[[S/2020 S 26]] (2020)
*[[S/2020 S 27]] (2020)
{{Div col end}}

; Uranus
Discovered [[moons of Uranus]] ([[Moons of Uranus#List|full list]]):<ref name="jpl-Satellite-Discovery-Circumstances" />
*[[Margaret (moon)|Margaret]] (2003)
*[[Ferdinand (moon)|Ferdinand]] (2003), first seen but lost in 2001 by Holman et al.
*[[S/2023 U 1]] (2023)

; Neptune
Discovered [[moons of Neptune]] ([[Moons of Neptune#List|full list]]):<ref name="jpl-Satellite-Discovery-Circumstances" />
*[[Psamathe (moon)|Psamathe]] (2003)
*[[S/2002 N 5]] (2021), first seen but lost in 2002 by Holman et al.
*[[S/2021 N 1]] (2021)

==See also==
*{{section link|List of minor planet discoverers|Discovering astronomers}}

==References==
{{Reflist
| refs =

<ref name="MPC-Discoverers">{{cite web
 |title       = Minor Planet Discoverers (by number)
 |work        = Minor Planet Center
 |url         = http://www.minorplanetcenter.net/iau/lists/MPDiscsNum.html
 |date        = 24 May 2019
 |access-date = 28 May 2019}}</ref>

<ref name="springer">{{cite book
 |title     = Dictionary of Minor Planet Names – (17898) Scottsheppard, Addendum to Fifth Edition: 2003–2005
 |last      = Schmadel | first = Lutz D.
 |publisher = Springer Berlin Heidelberg
 |page      = 112
 |date      = 2006
 |isbn      = 978-3-540-34361-5
 |doi       = 10.1007/978-3-540-34361-5_1203 |chapter       = (17898) Scottsheppard &#91;2.14, 0.05, 2.8&#93;}}</ref>

<ref name="circ8962">{{cite web
 |date        = 2008-08-01
 |title       = Circular No. 8962 Central Bureau for Astronomical Telegrams
 |publisher   = CBAT
 |url         = http://www.cbat.eps.harvard.edu/iauc/08900/08962.pdf
 |access-date = 2012-01-30}}</ref>

<ref name="jpl-Satellite-Discovery-Circumstances">{{cite web
 |title       = JPL Solar System Dynamics: Planetary Satellite Discovery Circumstances
 |url         = https://ssd.jpl.nasa.gov/?sat_discovery
 |publisher   = [[Jet Propulsion Laboratory]]
 |access-date = 7 October 2018}}</ref>

<ref name="CV">{{cite web
 |title       = Scott S. Sheppard – Curriculum Vitae
 |publisher   = [[Carnegie Institution for Science]]
 |url         = http://www.dtm.ciw.edu/users/sheppard/sheppardCV.pdf
 |access-date = 7 October 2018}}</ref>
}} <!-- end of reflist -->

==External links==
*[https://sites.google.com/carnegiescience.edu/sheppard/home Scott Sheppard's web site], [[Carnegie Institution for Science]]
*[https://epl.carnegiescience.edu/sites/dtm/files/20151001sheppardCV_0.pdf Scott S. Sheppard – Curriculum Vitae], Carnegie Institution for Science

{{Authority control}}

{{DEFAULTSORT:Sheppard, Scott S.}}
[[Category:1977 births]]
[[Category:Living people]]
[[Category:20th-century American astronomers]]
[[Category:21st-century American astronomers]]
[[Category:American planetary scientists]]
[[Category:Discoveries by Scott S. Sheppard|*]]
[[Category:Discoverers of moons]]
[[Category:Discoverers of trans-Neptunian objects]]
[[Category:Oberlin College alumni]]
[[Category:University of Hawaiʻi at Mānoa alumni]]