Themisto (moon): Difference between revisions

Themisto
Discovery
Discovered by	Charles Kowal (1975); Elizabeth Roemer (1975); Scott S. Sheppard (2000); David C. Jewitt (2000); Yanga R. Fernández (2000); Eugene A. Magnier (2000)
Discovery date	September 30, 1975; November 21, 2000 rediscovered
Designations
Pronunciation	/θɪˈmɪstoʊ/
Named after	Θεμιστώ Themistō
Alternative names	S/2000 J 1
Adjectives	Themistoan /θɛmɪˈstoʊ.ən/ or Themistoian /θɛmɪˈstoʊ.iən/
Orbital characteristics
Semi-major axis	7507000 km
Eccentricity	0.242
Orbital period (sidereal)	+130.0 days
Mean anomaly	134.2°
Inclination	43.08°
Longitude of ascending node	201.5°
Argument of perihelion	240.7°
Satellite of	Jupiter
Group	(own group)
Physical characteristics
Mean diameter	9 km
Mass	6.89×1014 kg[citation needed]
Mean density	2.6 g/cm3 (assumed)
Albedo	0.04 (assumed)
Temperature	~124 K
Apparent magnitude	21.0

Browse history interactively

← Previous edit Next edit →

Content deleted Content added

VisualWikitext

Inline

Revision as of 07:59, 14 March 2020

Themisto /θɪˈmɪstoʊ/, also known as Jupiter XVIII, is a small prograde irregular satellite of Jupiter. It was discovered in 1975, subsequently lost, and rediscovered in 2000.

Discovery and naming

Themisto was first discovered by Charles T. Kowal and Elizabeth Roemer on September 30, 1975, reported on October 3, 1975,^[6] and designated S/1975 J 1. However, not enough observations were made to establish an orbit and it was subsequently lost. (See also lost minor planet.)

Themisto appeared as a footnote in astronomy textbooks into the 1980s. Then, in 2000, a seemingly new satellite was discovered by Scott S. Sheppard, David C. Jewitt, Yanga R. Fernández and Eugene A. Magnier, and was designated S/2000 J 1. It was soon confirmed that this was the same as the one observed in 1975.^[7] This observation was immediately correlated with an observation on August 6, 2000, by the team of Brett J. Gladman, John J. Kavelaars, Jean-Marc Petit, Hans Scholl, Matthew J. Holman, Brian G. Marsden, Philip D. Nicholson and Joseph A. Burns, which was reported to the Minor Planet Center but not published as an IAU Circular (IAUC).^[8]

In October 2002 it was officially named after Themisto,^[9] daughter of the river god Inachus and lover of Zeus (Jupiter) in Greek mythology.

Characteristics

Themisto's orbit is unusual: unlike most of Jupiter's moons, which orbit in distinct groups, Themisto orbits alone. The moon is located midway between the Galilean moons and the first group of prograde irregular moons, called the Himalia group.

Themisto is about 8 kilometers (5 miles) in diameter (assuming an albedo of 0.04).^[5] That figure can be used to find a surface area of between 200 and 380 square kilometers.

References

^ Cf. 'Themista' in Noah Webster (1884) A Practical Dictionary of the English Language
^ 'Themis[t]oan' in James Hall (2015) Moons of the Solar System, p. 82.
^ S.S. Sheppard (2019), Moons of Jupiter, Carnegie Science, on line
^ "Planetary Satellite Physical Parameters". JPL.
^ ^a ^b Sheppard, S. S.; Jewitt, D. C.; An abundant population of small irregular satellites around Jupiter, Nature, 423 (May 15, 2003), pp. 261–263
^ Brian G. Marsden (October 3, 1975). "IAUC 2845: Probable New Satellite of Jupiter". International Astronomical Union Central Bureau for Astronomical Telegrams.
^ Brian G. Marsden (November 25, 2000). "IAUC 7525: S/1975 J 1 = S/2000 J 1". International Astronomical Union Central Bureau for Astronomical Telegrams.
^ "MPEC 2000-Y16: S/1975 J 1 = S/2000 J 1, S/1999 J 1". International Astronomical Union Minor Planet Center. December 19, 2000.
^ Daniel W. E. Green (October 22, 2002). "IAUC 7998: Satellites of Jupiter". International Astronomical Union.

"MPC: Natural Satellites Ephemeris Service". International Astronomical Union Minor Planet Center.
"Planetary Satellite Mean Orbital Parameters". JPL.

External links

[1] Cf. 'Themista' in Noah Webster (1884) A Practical Dictionary of the English Language

[2] 'Themis[t]oan' in James Hall (2015) Moons of the Solar System, p. 82.

[3] S.S. Sheppard (2019), Moons of Jupiter, Carnegie Science, on line

[physpars-4] "Planetary Satellite Physical Parameters". JPL.

[SheppardJewitt2003-5] Sheppard, S. S.; Jewitt, D. C.; An abundant population of small irregular satellites around Jupiter, Nature, 423 (May 15, 2003), pp. 261–263

[6] Brian G. Marsden (October 3, 1975). "IAUC 2845: Probable New Satellite of Jupiter". International Astronomical Union Central Bureau for Astronomical Telegrams.

[7] Brian G. Marsden (November 25, 2000). "IAUC 7525: S/1975 J 1 = S/2000 J 1". International Astronomical Union Central Bureau for Astronomical Telegrams.

[8] "MPEC 2000-Y16: S/1975 J 1 = S/2000 J 1, S/1999 J 1". International Astronomical Union Minor Planet Center. December 19, 2000.

[9] Daniel W. E. Green (October 22, 2002). "IAUC 7998: Satellites of Jupiter". International Astronomical Union.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

@@ Line 5: / Line 5: @@
 | image_size = 200
 | pronounced = {{IPAc-en|θ|ᵻ|ˈ|m|ɪ|s|t|oʊ}}<ref>Cf. 'Themista' in Noah Webster (1884) ''A Practical Dictionary of the English Language''</ref>
-| adjectives = Themistoan {{IPAc-en|θ|ɛ|m|ᵻ|ˈ|s|t|oʊ|.|ə|n}} or {{nowrap|Themistoian {{IPAc-en|θ|ɛ|m|ᵻ|ˈ|s|t|oʊ|.|i|ə|n}}}}
+| adjectives = Themistoan {{IPAc-en|θ|ɛ|m|ᵻ|ˈ|s|t|oʊ|.|ə|n}}<ref>'Themis[t]oan' in James Hall (2015) ''Moons of the Solar System'', p. 82.</ref> or {{nowrap|Themistoian {{IPAc-en|θ|ɛ|m|ᵻ|ˈ|s|t|oʊ|.|i|ə|n}}}}
 | named_after = [[Themisto (nymph)|Θεμιστώ]] ''Themistō
 | alt_names = S/2000 J 1

v t e Moons of Jupiter
Listed in increasing approximate distance from Jupiter
Inner moons	Metis Adrastea Amalthea Thebe
Galilean moons	Io Europa Ganymede Callisto
Themisto	Themisto
Himalia group (9)	Leda Ersa S/2018 J 2 Himalia Pandia Lysithea Elara S/2011 J 3 Dia
Carpo group (2)	S/2018 J 4 Carpo
Valetudo	Valetudo
Ananke group (26)	Euporie Jupiter LV Eupheme S/2021 J 3 Jupiter LII Jupiter LIV Mneme Euanthe S/2003 J 16 Harpalyke Orthosie S/2022 J 3 Helike S/2021 J 2 Praxidike Jupiter LXIV S/2021 J 1 S/2003 J 12 Jupiter LXVIII Thelxinoe Thyone S/2003 J 2 Ananke Iocaste Hermippe Jupiter LXX
Carme group (30)	S/2022 J 1 S/2022 J 2 S/2016 J 3 Pasithee Jupiter LXIX S/2021 J 6 S/2003 J 24 Chaldene Jupiter LXIII Isonoe S/2021 J 4 Kallichore Erinome Kale Eirene Aitne Eukelade Arche Taygete Jupiter LXXII Carme Herse Jupiter LXI Jupiter LI S/2003 J 9 Jupiter LXVI Kalyke S/2018 J 3 S/2021 J 5 S/2003 J 10
Pasiphae group (18)	Philophrosyne Eurydome Jupiter LVI S/2003 J 4 S/2016 J 4 Jupiter LXVII Hegemone Pasiphae Sponde Megaclite Cyllene Sinope Jupiter LIX Aoede Autonoe Callirrhoe S/2003 J 23 Kore
See also	Rings of Jupiter Jupiter's moons in fiction
Category