Ophelia (moon)

Ophelia
	Ophelia (image taken 21 January 1986)
Discovery
Discovered by	Richard J. Terrile / Voyager 2
Discovery date	January 20, 1986
Designations
Designation	Uranus VII
Pronunciation	/oʊˈfiːliə/
Adjectives	Ophelian /ɒˈfiːliən/
Orbital characteristics
Semi-major axis	53763.390±0.847 km
Eccentricity	0.00992±0.000107
Orbital period (sidereal)	0.37640039±0.00000357 d
Average orbital speed	10.39 km/s
Inclination	0.10362°±0.055° (to Uranus' equator)
Satellite of	Uranus
Group	ring shepherd
Physical characteristics
Dimensions	54 × 38 × 38 km
Surface area	~5900 km2
Volume	40800±50.4% km3
Mass	(3.57±0.32)×1016 kg
Mean density	0.87+0.89; −0.30 g/cm3
Surface gravity	~0.003–0.007 m/s2
Escape velocity	~0.013–0.016 km/s
Synodic rotation period	synchronous
Axial tilt	zero
Albedo	0.065±0.01; 0.07
Temperature	~65 K
	^ Only two dimensions are known; the third dimension has been assumed to equal the smaller known dimension. ;

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 U 8.^[1] It was not seen again until the Hubble Space Telescope recovered it in 2003.^[7]^[9] Ophelia was named after the daughter of Polonius, Ophelia, in William Shakespeare's play Hamlet. It is also designated Uranus VII.^[10]

Other than its orbit,^[4] size of 54 × 38 km,^[5] and geometric albedo of 0.065,^[7] 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.^[5]

Ophelia acts as the outer shepherd satellite for Uranus's ε ring.^[11] The orbit of Ophelia is within the synchronous orbit radius of Uranus, and is therefore slowly decaying due to tidal forces.^[5]

^ ^a ^b Cite error: The named reference IAUC 4168 was invoked but never defined (see the help page).
^ Benjamin Smith (1903). The Century Dictionary and Cyclopedia.
^ "Ophelian". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
^ ^a ^b ^c Cite error: The named reference Jacobson 1998 was invoked but never defined (see the help page).
^ ^a ^b ^c ^d ^e ^f Cite error: The named reference Karkoschka, Voyager 2001 was invoked but never defined (see the help page).
^ ^a ^b ^c Cite error: The named reference FrenchEtAl2024 was invoked but never defined (see the help page).
^ ^a ^b ^c Cite error: The named reference Karkoschka, Hubble 2001 was invoked but never defined (see the help page).
^ Cite error: The named reference Williams 2007 nssdc was invoked but never defined (see the help page).
^ Cite error: The named reference IAUC 8194 was invoked but never defined (see the help page).
^ Cite error: The named reference Gazetteer was invoked but never defined (see the help page).
^ Cite error: The named reference Esposito 2002 was invoked but never defined (see the help page).

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[7] Only two dimensions are known; the third dimension has been assumed to equal the smaller known dimension.

[IAUC_4168-1] Cite error: The named reference IAUC 4168 was invoked but never defined (see the help page).

[2] Benjamin Smith (1903). The Century Dictionary and Cyclopedia.

[3] "Ophelian". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)

[Jacobson_1998-4] Cite error: The named reference Jacobson 1998 was invoked but never defined (see the help page).

[Karkoschka,_Voyager_2001-6] ^ ^a ^b ^c ^d ^e ^f Cite error: The named reference Karkoschka, Voyager 2001 was invoked but never defined (see the help page).

[FrenchEtAl2024-8] Cite error: The named reference FrenchEtAl2024 was invoked but never defined (see the help page).

[Karkoschka,_Hubble_2001-9] Cite error: The named reference Karkoschka, Hubble 2001 was invoked but never defined (see the help page).

[Williams_2007_nssdc-10] Cite error: The named reference Williams 2007 nssdc was invoked but never defined (see the help page).

[IAUC_8194-11] Cite error: The named reference IAUC 8194 was invoked but never defined (see the help page).

[Gazetteer-12] Cite error: The named reference Gazetteer was invoked but never defined (see the help page).

[Esposito_2002-13] Cite error: The named reference Esposito 2002 was invoked but never defined (see the help page).

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[note 1]

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Discovery^[1]
Ophelia (image taken 21 January 1986)
Discovered by	Richard J. Terrile / Voyager 2
Discovery date	January 20, 1986
Designations
Designation	Uranus VII
Pronunciation	/oʊˈfiːliə/^[2]
Adjectives	Ophelian /ɒˈfiːliən/^[3]
Orbital characteristics^[4]
Semi-major axis	53763.390±0.847 km
Eccentricity	0.00992±0.000107
Orbital period (sidereal)	0.37640039±0.00000357 d
Average orbital speed	10.39 km/s^[a]
Inclination	0.10362°±0.055° (to Uranus' equator)^[4]
Satellite of	Uranus
Group	ring shepherd
Physical characteristics
Dimensions	54 × 38 × 38 km^[5]^{[note 1]}
Surface area	~5900 km²^[a]
Volume	40800±50.4% km³^[6]
Mass	(3.57±0.32)×10¹⁶ kg^[6]
Mean density	0.87+0.89 −0.30 g/cm³^[6]
Surface gravity	~0.003–0.007 m/s²^[a]
Escape velocity	~0.013–0.016 km/s^[a]
Synodic rotation period	synchronous^[5]
Axial tilt	zero^[5]
Albedo	0.065±0.01^[7] 0.07^[8]
Temperature	~65 K^[a]
^ Only two dimensions are known; the third dimension has been assumed to equal the smaller known dimension.