Editing Ophelia (moon)

{{Short description|Moon of Uranus}}
{{Infobox planet
| name             = Ophelia
| image            = Opheliamoon.png
| caption          = Ophelia (image taken 21 January 1986)
| mpc_name         = Uranus VII
| pronounced       = {{IPAc-en|oʊ|ˈ|f|iː|l|i|ə}}<ref>{{cite book|author=Benjamin Smith|year=1903|title=The Century Dictionary and Cyclopedia}}</ref>
| adjective        = Ophelian {{IPAc-en|ɒ|ˈ|f|iː|l|i|ə|n}}<ref>{{OED|Ophelian}}</ref>
| discovery_ref    = <ref name="IAUC 4168" />
| discoverer       = [[Richard J. Terrile]] / ''[[Voyager 2]]''
| discovered       = January 20, 1986
| orbit_ref        = <ref name="Jacobson 1998"/>
| semimajor        = {{val|53763.390|0.847|u=km}}
| eccentricity     = {{val|0.00992|0.000107}}
| period           = {{val|0.37640039|0.00000357|u=d}}
| avg_speed        = 10.39 km/s{{efn|name=calculated}}
| inclination      = {{val|0.10362|0.055|u=°}} (to Uranus's equator)<ref name="Jacobson 1998" />
| satellite_of     = [[Uranus]]
| group            = [[ring shepherd]]
| dimensions       = 54 × 38 × 38 km<ref name="Karkoschka, Voyager 2001" />{{refn|group=note|Only two dimensions are known; the third dimension has been assumed to equal the smaller known dimension.}}
| surface_area     = ~5900 km<sup>2</sup>{{efn|name=calculated}}
| volume           = {{val|40800|50.4|u=km3|errend=%}}<ref name = "FrenchEtAl2024"/>
| mass             = {{val|3.57|0.32|u=kg|e=16}}<ref name = "FrenchEtAl2024"/>
| density          = {{val|0.87|0.89|0.30|u=g/cm3}}<ref name = "FrenchEtAl2024"/>
| surface_grav     = ~{{Gr|3.57e-5|27}}–{{Gr|3.57e-5|19}} [[Acceleration|m/s<sup>2</sup>]]{{efn|name=calculated}}
| escape_velocity  = ~{{V2|3.57e-5|27}}–{{V2|3.57e-5|19}} km/s{{efn|name=calculated}}
| rotation         = synchronous<ref name="Karkoschka, Voyager 2001" />
| axial_tilt       = zero<ref name="Karkoschka, Voyager 2001" />
| albedo           = {{val|0.065|0.01}}<ref name="Karkoschka, Hubble 2001" /><br>0.07<ref name="Williams 2007 nssdc" />
| single_temperature = ~65 [[Kelvin|K]]{{efn|name=calculated}}
}}

'''Ophelia''' is a moon of [[Uranus]]. It was discovered from the images taken by ''[[Voyager 2]]'' on January 20, 1986, and was given the temporary designation '''S/1986&nbsp;U&nbsp;8'''.<ref name="IAUC 4168" /> It was not seen again until the [[Hubble Space Telescope]] recovered it in 2003.<ref name="Karkoschka, Hubble 2001" /><ref name="IAUC 8194" /> Ophelia was named after the daughter of [[Polonius]], [[Ophelia (character)|Ophelia]], in [[William Shakespeare]]'s play ''[[Hamlet]]''. It is also designated '''Uranus&nbsp;VII'''.<ref name="Gazetteer" />

Other than its orbit,<ref name="Jacobson 1998" /> size of 54 × 38 km,<ref name="Karkoschka, Voyager 2001" /> and geometric albedo of 0.065,<ref name="Karkoschka, Hubble 2001" /> virtually nothing is known about it. In ''[[Voyager 2]]'', images Ophelia appears as an elongated object, with its major axis pointing towards Uranus. The ratio of axes of the Ophelia's prolate spheroid is 0.7 ± 0.3.<ref name="Karkoschka, Voyager 2001" />

Ophelia acts as the outer [[shepherd satellite]] for Uranus's [[Rings_of_Uranus#ε_(epsilon)_ring|ε ring]].<ref name="Esposito 2002" /> The orbit of Ophelia is within the synchronous orbit radius of Uranus, and is therefore slowly decaying due to [[tidal force]]s.<ref name="Karkoschka, Voyager 2001" />

== See also ==

* [[Moons of Uranus]]

== Notes ==
{{notes
| notes =

{{efn
| name = calculated
| Calculated on the basis of other parameters.
}}

}}

== References ==
{{reflist
| refs =

<ref name="Jacobson 1998">
{{cite journal| doi = 10.1086/300263| last1 = Jacobson| first1 = R. A.| year = 1998| title = The Orbits of the Inner Uranian Satellites From Hubble Space Telescope and Voyager 2 Observations| journal = The Astronomical Journal| volume = 115| issue = 3| pages = 1195–1199| bibcode = 1998AJ....115.1195J| s2cid = 118616209| doi-access = free}}
</ref>

<ref name="Karkoschka, Voyager 2001">
{{cite journal| doi = 10.1006/icar.2001.6597| last = Karkoschka| first = Erich| author-link = Erich Karkoschka| year = 2001| title = Voyager's Eleventh Discovery of a Satellite of Uranus and Photometry and the First Size Measurements of Nine Satellites| journal = Icarus| volume = 151| issue = 1| pages = 69–77| bibcode = 2001Icar..151...69K| ref = {{sfnRef|Karkoschka, Voyager|2001}}}}
</ref>

<ref name="Williams 2007 nssdc">
{{cite web
| last = Williams
| first = Dr. David R.
| date = 23 November 2007
| title = Uranian Satellite Fact Sheet
| publisher = [[NASA]] (National Space Science Data Center)
| url = http://nssdc.gsfc.nasa.gov/planetary/factsheet/uraniansatfact.html
| access-date = 12 December 2008
}}
</ref>

<ref name="Karkoschka, Hubble 2001">
{{cite journal| doi = 10.1006/icar.2001.6596| last = Karkoschka| first = Erich| author-link = Erich Karkoschka| year = 2001| title = Comprehensive Photometry of the Rings and 16 Satellites of Uranus with the Hubble Space Telescope| journal = Icarus| volume = 151| issue = 1| pages = 51–68| bibcode = 2001Icar..151...51K| ref = {{sfnRef|Karkoschka, Hubble|2001}}}}
</ref>

<ref name="IAUC 4168">
{{cite journal
| last = Smith
| first = B. A.
| title = Satellites and Rings of Uranus
| journal = IAU Circular
| volume = 4168
| date = 1986-01-27
| url = http://www.cbat.eps.harvard.edu/iauc/04100/04168.html#item1
| access-date = 2011-10-31
}}
</ref>

<ref name="IAUC 8194">
{{cite journal
| last1 = Showalter
| first1 = M. R.
| last2 = Lissauer
| first2 = J. J.
| title = Satellites of Uranus
| journal = IAU Circular
| volume = 8194
| date = 2003-09-03
| url = http://www.cbat.eps.harvard.edu/iauc/08100/08194.html
| access-date = 2011-10-31
}}
</ref>

<ref name="Gazetteer">
{{cite web
| title = Planet and Satellite Names and Discoverers
| work = Gazetteer of Planetary Nomenclature
| publisher = USGS Astrogeology
| date = July 21, 2006
| url = http://planetarynames.wr.usgs.gov/append7.html
| access-date = 6 August 2006
| archive-url = https://web.archive.org/web/20160305150456/http://planetarynames.wr.usgs.gov/Page/Planets
| archive-date = 5 March 2016
}}
</ref>

<ref name="Esposito 2002">
{{cite journal| doi = 10.1088/0034-4885/65/12/201| last = Esposito| first = L. W.| author-link = Larry W. Esposito| year = 2002| title = Planetary rings| journal = Reports on Progress in Physics| volume = 65| issue = 12| pages = 1741–1783| bibcode = 2002RPPh...65.1741E| s2cid = 250909885}}
</ref>

<ref name = "FrenchEtAl2024">
{{Cite journal |last=French |first=Richard G. |last2=Hedman |first2=Matthew M. |last3=Nicholson |first3=Philip D. |last4=Longaretti |first4=Pierre-Yves |last5=McGhee-French |first5=Colleen A. |date=2024-03-15 |title=The Uranus system from occultation observations (1977–2006): Rings, pole direction, gravity field, and masses of Cressida, Cordelia, and Ophelia |url=https://www.sciencedirect.com/science/article/pii/S0019103524000150 |journal=Icarus |volume=411 |pages=115957 |doi=10.1016/j.icarus.2024.115957 |issn=0019-1035|arxiv=2401.04634 }}
</ref>

}}

== External links ==
* [https://web.archive.org/web/20070801203853/http://solarsystem.nasa.gov/planets/profile.cfm?Object=Ura_Ophelia Ophelia Profile] by [http://solarsystem.nasa.gov NASA's Solar System Exploration]
* [http://www.dtm.ciw.edu/users/sheppard/satellites/urasatdata.html Uranus' Known Satellites] (by [[Scott S. Sheppard]])

{{Uranus}}
{{Moons of Uranus}}
{{Solar System moons (compact)}}

{{DEFAULTSORT:Ophelia (Moon)}}
[[Category:Astronomical objects discovered in 1986|19860120]]
[[Category:Discoveries by Richard J. Terrile]]
[[Category:Ophelia]]
[[Category:Moons of Uranus]]
[[Category:Moons with a prograde orbit]]