Movatterモバイル変換

S/2020 S 4

From Wikipedia, the free encyclopedia

Moon of Saturn

S/2020 S 4
Discovery
Discovered by	Edward Ashton,Brett J. Gladman
Discovery date	2020
Orbital characteristics^[1]
Semi-major axis	18,235,500 km (11,331,000 mi)
Eccentricity	0.495
Orbital period (sidereal)	2.538 yrs (926.96 d)
Inclination	40.1°(to theecliptic)
Satellite of	Saturn
Group	Gallic group
Physical characteristics
Mean diameter	3 km
Absolute magnitude (H)	17.0

S/2020 S 4 is a small and very faintnatural satellite ofSaturn. It was discovered by Edward Ashton,Brett J. Gladman,Jean-Marc Petit and Mike Alexandersen on June 24, 2020, and was announced on May 6, 2023 by theIAU Minor Planet Center after observations were collected over a long period of time to confirm the satellite's orbit that were taken between July 1, 2019 and July 9, 2021.^[2]

Orbit

[edit]

S/2020 S 4 is a highly eccentric satellite with aneccentricity of 0.495, it orbits Saturn at an average distance of 18.2 million km and has an orbital period of 2 and a half years, with an inclination of 40.1° to theecliptic, suggesting that it belongs to theGallic group.^[1] However, sometimes its moon group is disputed, and it may be included in theInuit group.^[3]^[4] It has been suggested that it was a fragment piece ofSiarnaq that broke off a long time ago in a time-span of a few thousand years.^[3]

The orbit of S/2020 S 4 is librating in accordance of thevon Zeipel–Lidov–Kozai effect.^[5]

Physical characteristics

[edit]

S/2020 S 4 is estimated to be 3 km in diameter and has anabsolute magnitude of 17, making it one of the faintest moons of Saturn.^[1]Scott S. Sheppard and Tilmann Denk on the other hand, estimated it to be 2 km and 2.25 km, respectively.^[4]^[3] If these estimates were true, it would make S/2020 S 4 one of the smallest knownirregular moons of Saturn.^[3]

References

[edit]

^^a ^b ^c"Planetary Satellite Mean Elements".Jet Propulsion Laboratory. California Institute of Technology. Retrieved6 May 2023.
^"MPEC 2023-J38 : S/2020 S 4".Minor Planet Electronic Circular. Minor Planet Center. Retrieved6 May 2023.
^^a ^b ^c ^d"S/2020 S 4".Tilmann's Website. Tilmann Denk. Retrieved23 March 2024.
^^a ^b"Saturn Moons".Carnegie Science. Earth & Planets Laboratory. Retrieved23 March 2024.
^Grishin, Evgeni (September 2024)."Irregular Fixation II: The orbits of irregular satellites".Monthly Notices of the Royal Astronomical Society.533 (1):497–509.arXiv:2407.05123.Bibcode:2024MNRAS.533..497G.doi:10.1093/mnras/stae1752.

Moons of Saturn

Listed in approximate increasing distance from Saturn

Ring moonlets

Ring shepherds

Alkyonides

Large moons
(withtrojans)

Inuit group (36)

Kiviuq subgroup (20)	S/2023 S 1 S/2019 S 1 S/2004 S 54 S/2004 S 55 S/2020 S 11 S/2019 S 22 Kiviuq S/2023 S 2 S/2019 S 23 S/2020 S 12 S/2005 S 4 S/2019 S 25 S/2020 S 1 Ijiraq S/2019 S 24 S/2007 S 10 S/2019 S 26 S/2020 S 13 S/2023 S 6 S/2023 S 7
Paaliaq	Paaliaq
Siarnaq subgroup (15)	S/2004 S 31 S/2023 S 19 S/2023 S 3 S/2020 S 19 Tarqeq S/2019 S 14 Siarnaq S/2019 S 32 S/2020 S 3 S/2005 S 6 S/2019 S 6 S/2004 S 58 S/2006 S 23 S/2020 S 5 S/2023 S 22

Gallic group (17)

Albiorix
S/2020 S 15
Bebhionn
S/2007 S 8
Saturn LX
S/2019 S 29
S/2023 S 18
S/2023 S 17
S/2007 S 11
Erriapus
S/2019 S 31
Tarvos
S/2020 S 4
S/2019 S 34
S/2005 S 7
S/2006 S 12
S/2004 S 24

Norse group (197)

Low-inclination (12)	S/2023 S 38 Skathi S/2020 S 17 S/2023 S 20 S/2023 S 30 Hyrrokkin Narvi S/2019 S 37 Bestla S/2019 S 11 S/2020 S 27 S/2023 S 46
Kari subgroup (15)	S/2006 S 1 S/2004 S 45 S/2023 S 27 S/2006 S 3 S/2023 S 33 S/2020 S 30 Kari Geirrod S/2019 S 17 S/2019 S 19 S/2019 S 18 S/2004 S 21 S/2004 S 36 S/2019 S 20 S/2006 S 29
Mundilfari subgroup (143)	S/2023 S 50 S/2023 S 9 S/2004 S 56 S/2023 S 8 S/2023 S 11 S/2006 S 21 S/2006 S 22 S/2023 S 13 S/2023 S 10 S/2023 S 12 S/2007 S 5 S/2007 S 7 S/2004 S 37 S/2004 S 47 S/2004 S 40 S/2020 S 14 S/2019 S 27 S/2023 S 14 S/2020 S 16 S/2023 S 16 S/2019 S 3 S/2020 S 7 S/2019 S 28 Skoll S/2019 S 30 S/2023 S 21 S/2023 S 4 S/2020 S 18 S/2020 S 2 S/2019 S 4 S/2020 S 20 S/2004 S 41 S/2004 S 57 S/2006 S 24 S/2004 S 42 S/2023 S 15 S/2023 S 24 S/2004 S 13 S/2007 S 6 S/2019 S 35 S/2006 S 25 Mundilfari S/2006 S 26 S/2019 S 33 S/2023 S 23 S/2020 S 21 S/2004 S 43 S/2006 S 10 S/2019 S 5 S/2023 S 25 S/2004 S 59 S/2006 S 27 Gridr Bergelmir Jarnsaxa S/2023 S 44 S/2020 S 22 S/2004 S 44 Hati S/2004 S 17 S/2004 S 12 S/2020 S 23 Eggther S/2023 S 28 S/2023 S 37 S/2023 S 26 S/2019 S 36 S/2006 S 13 S/2023 S 48 S/2023 S 29 S/2007 S 9 Farbauti S/2019 S 9 S/2023 S 32 S/2020 S 24 Aegir S/2019 S 10 Beli S/2023 S 31 S/2020 S 25 S/2023 S 34 S/2023 S 39 S/2019 S 12 S/2004 S 61 S/2006 S 14 S/2023 S 40 Gunnlod S/2019 S 15 S/2020 S 6 S/2020 S 26 S/2023 S 41 S/2004 S 7 S/2005 S 5 S/2006 S 16 S/2023 S 49 S/2006 S 15 S/2023 S 42 S/2004 S 28 S/2020 S 32 S/2020 S 8 S/2020 S 28 S/2019 S 38 S/2004 S 48 S/2023 S 36 S/2023 S 35 S/2020 S 29 Fenrir S/2004 S 50 S/2006 S 17 S/2004 S 49 S/2020 S 34 S/2020 S 31 S/2023 S 43 Surtur S/2006 S 18 S/2020 S 36 Loge S/2020 S 33 S/2004 S 39 S/2019 S 16 S/2004 S 53 S/2023 S 45 Thiazzi S/2020 S 38 S/2020 S 40 S/2019 S 40 S/2019 S 42 Saturn LXIV S/2020 S 39 S/2019 S 41 Fornjot S/2023 S 47 S/2004 S 51 S/2020 S 10 S/2020 S 42 S/2020 S 9 S/2023 S 5 S/2020 S 41 S/2019 S 21 S/2004 S 52 S/2020 S 43 S/2019 S 43 S/2020 S 44
Phoebe subgroup (27)	Phoebe S/2006 S 20 S/2006 S 9 S/2007 S 2 S/2019 S 2 Greip Suttungr S/2004 S 60 S/2007 S 3 S/2006 S 11 S/2019 S 7 S/2019 S 8 Thrymr S/2004 S 46 Angrboda Gerd S/2019 S 13 Skrymir S/2006 S 28 Alvaldi Ymir S/2020 S 35 S/2020 S 37 S/2019 S 39 S/2006 S 19 Saturn LVIII S/2019 S 44

Retrieved from "https://en.wikipedia.org/w/index.php?title=S/2020_S_4&oldid=1317598910"

Categories:

Hidden categories:

[8]ページ先頭