Prometheus (moon)

Prometheus
	Prometheus image from Cassini (December 26, 2009)
Discovery
Discovered by	Stewart A. Collins; D. Carlson; Voyager 1
Discovery date	October, 1980
Designations
Designation	Saturn XVI
Pronunciation	/prəˈmiːθiːəs/
Named after	Προμηθεύς Promētheys
Adjectives	Promethean, -ian /prəˈmiːθiːən/
Orbital characteristics
	Epoch 31 December 2003 (JD 2453005.5)
Semi-major axis	139380±10 km
Eccentricity	0.0022
Orbital period (sidereal)	0.612990038 d
Inclination	0.008°±0.004° to Saturn's equator
Satellite of	Saturn
Group	Inner shepherd moon of the F Ring
Physical characteristics
Dimensions	137.0 × 81.0 × 56.2 km; (± 1.0 × 2.8 × 0.8 km)
Mean diameter	85.6±1.4 km
Volume	327740±1710 km3
Mass	(1.59720±0.00072)×1017 kg
Mean density	0.4873±0.0026 g/cm3
Surface gravity	0.0007–0.0056 m/s2
Escape velocity	0.018 km/s at longest axis; to 0.028 km/s at poles
Synodic rotation period	synchronous
Axial tilt	zero
Albedo	0.6
Temperature	≈ 74 K

Prometheus /prəˈmiːθiːəs/ is an inner satellite of Saturn. It was discovered on 24 October 1980 from photos taken by the Voyager 1 probe, and was provisionally designated S/1980 S 27.^[6]

In late 1985 it was officially named after Prometheus, a Titan in Greek mythology.^[7] It is also designated Saturn XVI.^[8]

Prometheus is extremely elongated, measuring approximately 137 km × 81 km × 56 km (85 mi × 50 mi × 35 mi). It has several ridges and valleys and a number of impact craters of about 20 km (12 mi) diameter are visible, but it is less cratered than nearby Pandora, Epimetheus, and Janus. From its very low density and relatively high albedo, it is likely that Prometheus is a very porous icy body. There is much uncertainty in these values, however, and so this remains to be confirmed.

^ "Prometheus". Lexico UK English Dictionary. Oxford University Press. Archived from the original on March 20, 2020.
^ "Promethean". Lexico UK English Dictionary UK English Dictionary. Oxford University Press. Archived from the original on March 20, 2020.
^ Spitale Jacobson et al. 2006.
^ ^a ^b ^c Thomas & Helfenstein 2020.
^ ^a ^b ^c Lainey et al. 2023.
^ IAUC 3532.
^ IAUC 4157.
^ USGS: Planet and Satellite Names and Discoverers.

Cite error: There are <ref group=lower-alpha> tags or {{efn}} templates on this page, but the references will not show without a {{reflist|group=lower-alpha}} template or {{notelist}} template (see the help page).

[1] "Prometheus". Lexico UK English Dictionary. Oxford University Press. Archived from the original on March 20, 2020.

[2] "Promethean". Lexico UK English Dictionary UK English Dictionary. Oxford University Press. Archived from the original on March 20, 2020.

[FOOTNOTESpitale_Jacobson_et_al.2006-3] Spitale Jacobson et al. 2006.

[FOOTNOTEThomas_&_Helfenstein2020-4] Thomas & Helfenstein 2020.

[FOOTNOTELainey_et_al.2023-5] Lainey et al. 2023.

[FOOTNOTEIAUC_3532-7] IAUC 3532.

[FOOTNOTEIAUC_4157-8] IAUC 4157.

[FOOTNOTEUSGS:_Planet_and_Satellite_Names_and_Discoverers-9] USGS: Planet and Satellite Names and Discoverers.

[1]

[2]

[3]

[4]

[5]

[a]

[6]

[7]

[8]

Discovery
Prometheus image from Cassini (December 26, 2009)
Discovered by	Stewart A. Collins D. Carlson Voyager 1
Discovery date	October, 1980
Designations
Designation	Saturn XVI
Pronunciation	/prəˈmiːθiːəs/^[1]
Named after	Προμηθεύς Promētheys
Adjectives	Promethean, -ian /prəˈmiːθiːən/^[2]
Orbital characteristics ^[3]
Epoch 31 December 2003 (JD 2453005.5)
Semi-major axis	139380±10 km
Eccentricity	0.0022
Orbital period (sidereal)	0.612990038 d
Inclination	0.008°±0.004° to Saturn's equator
Satellite of	Saturn
Group	Inner shepherd moon of the F Ring
Physical characteristics
Dimensions	137.0 × 81.0 × 56.2 km (± 1.0 × 2.8 × 0.8 km)^[4]^: 2
Mean diameter	85.6±1.4 km^[4]^: 2
Volume	327740±1710 km³^[5]^: 4
Mass	(1.59720±0.00072)×10¹⁷ kg^[a]
Mean density	0.4873±0.0026 g/cm³^[5]^: 4
Surface gravity	0.0007–0.0056 m/s²^[4]^: 3
Escape velocity	0.018 km/s at longest axis to 0.028 km/s at poles
Synodic rotation period	synchronous
Axial tilt	zero
Albedo	0.6
Temperature	≈ 74 K