Vanth (moon)

Vanth
Vanth (smaller object) orbiting Orcus, imaged by the Hubble Space Telescope.
Discovery[1]
Discovered by
Discovery date13 November 2005
Designations
Designation
(90482) Orcus I[3]: 350 
Pronunciation/ˈvænθ/
S/2005 (90482) 1[4]
AdjectivesVanthian
Orbital characteristics[5]: 67 
Epoch 21.5 September 2006 (JD 2454000.0)
8999.8±9.1 km
Eccentricity0.00091±0.00053
9.539154±0.000020 d
Inclination105.03°±0.18° (to celestial equator)
90.54°±0.17° (to ecliptic)[a]
53.49°±0.33°
274.51°[b]
Satellite ofOrcus
Physical characteristics
442.5±10.2 km (occultation)[6]: 663 
475±75 km (thermal)[7]: 1 [8]: 2 
Mass(8.7±0.8)×1019 kg[8]: 4 
Mean density
1.9±0.3 g/cm3 (occultation)[c]
1.5+1.0
−0.5 g/cm3 (thermal)[8]: 4 
synchronous[9]: 6 [10]
Albedo0.08±0.02[7]
Temperature<44 K[6]: 663 
Spectral type
moderately red[11]: 2702 
V–I = 1.03±0.05[11]: 2702 
21.8[12]
4.88±0.05[11]: 2702 

Vanth (formal designation (90482) Orcus I; provisional designation S/2005 (90482) 1) is a natural satellite or moon of the large trans-Neptunian dwarf planet Orcus. It was discovered by Michael Brown and Terry-Ann Suer using images taken by the Hubble Space Telescope on 13 November 2005. The moon has a diameter of 443 km (275 mi), making it about half the size of Orcus and the third-largest moon of a trans-Neptunian object. Vanth is massive enough that it shifts the barycenter of the Orcus–Vanth system outside of Orcus, forming a binary system in which the two bodies revolve around the barycenter, much like the Pluto–Charon system. It is hypothesized that both systems formed similarly, most likely by a giant impact early in the Solar System's history.[8] Compared to Orcus, Vanth has a darker and slightly redder surface that supposedly lacks exposed water ice, resembling primordial Kuiper belt objects.[11]: 2702 

  1. ^ Cite error: The named reference IAUC8812 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference Suer was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference MPC69496 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference jpldata was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference Grundy2019 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Sickafoose2019 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Brown2018 was invoked but never defined (see the help page).
  8. ^ a b c d e Cite error: The named reference Brown2023 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Ortiz2011 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Rabinowitz2014 was invoked but never defined (see the help page).
  11. ^ a b c d Cite error: The named reference Brown2010 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Grundy-tnbs was invoked but never defined (see the help page).


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).