Themisto (moon)

Themisto
Rediscovery images of Themisto taken by the UH88 telescope in November 2000
Discovery[1][2]
Discovered byCharles T. Kowal (1975)
Elizabeth P. Roemer (1975)
Scott S. Sheppard (2000)
David C. Jewitt (2000)
Yanga R. Fernández (2000)
Eugene A. Magnier (2000)
Discovery sitePalomar Observatory
Mauna Kea Observatory (rediscovery)
Discovery date30 September 1975
21 November 2000 (rediscovery)
Designations
Designation
Jupiter XVIII
Pronunciation/θəˈmɪstoʊ/[3]
Named after
Θεμιστώ Themistō
S/2000 J 1
S/1975 J 1
AdjectivesThemistoan /θɛməˈstoʊ.ən/[4] Themistoian /θɛməˈstoʊ.iən/
Orbital characteristics[5]
Epoch 23 March 2018 (JD 2458200.5)
Observation arc42.54 yr (15,536 days)
0.0494401 AU (7,396,130 km)
Eccentricity0.2522112
+129.95 d
2.39396°
2° 46m 13.369s / day
Inclination45.28121° (to ecliptic)
192.64162°
241.25168°
Satellite ofJupiter
Group(own group)
Physical characteristics
9 km[6]
16.4 km[7]
Albedo0.04 (assumed)
21.0[6]
12.9[5]
13.06±0.34 (V)[7]

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

  1. ^ Cite error: The named reference IAUC2845 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference IAUC7525 was invoked but never defined (see the help page).
  3. ^ Cf. 'Themista' in Noah Webster (1884). A Practical Dictionary of the English Language.
  4. ^ 'Themis[t]oan' in James Hall (2015). Moons of the Solar System. p. 82.
  5. ^ a b Cite error: The named reference MPC110499 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference SheppardMoons was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference EmelyanovEtAl2022 was invoked but never defined (see the help page).