4 Vesta

4 Vesta
True color image of Vesta taken by Dawn. The massive Rheasilvia Crater dominates Vesta's south pole.
Discovery
Discovered byHeinrich Wilhelm Olbers
Discovery date29 March 1807
Designations
(4) Vesta
Pronunciation/ˈvɛstə/[1]
Named after
Vesta
Minor planet category
Main belt (Vesta family)
Adjectives
  • Vestan
  • Vestian[a]
Symbol (historically astronomical, now astrological)
Orbital characteristics[6]
Epoch 13 September 2023
(JD 2453300.5)
Aphelion2.57 AU (384 million km)
Perihelion2.15 AU (322 million km)
2.36 AU (353 million km)
Eccentricity0.0894
3.63 yr (1325.86 d)
Average orbital speed
19.34 km/s
169.4°
Inclination7.1422° to ecliptic
5.58° to invariable plane[7]
103.71°
26 December 2021[8]
Argument of perihelion
151.66°
SatellitesNone
Earth MOID1.14 AU (171 million km)
Proper orbital elements[9]
2.36151 AU
0.098758
6.39234°
Proper mean motion
99.1888 deg / yr
3.62944 yr
(1325.654 d)
Precession of perihelion
36.8729 (2343 years) arcsec / yr
Precession of the ascending node
−39.5979 (2182 years) arcsec / yr
Physical characteristics
Dimensions572.6 km × 557.2 km × 446.4 km[10]
Mean diameter
525.4±0.2 km[10]
Flattening0.2204
(8.66±0.2)×105 km2[b][11]
Volume7.4970×107 km3[10]
Mass(2.590271±0.000058)×1020 kg[12]
Mean density
3.456±0.035 g/cm3[10]
Equatorial surface gravity
0.22 m/s2 (0.022 g0)
Equatorial escape velocity
0.36 km/s
Synodic rotation period
0.2226 d (5.342 h)[6][13]
Equatorial rotation velocity
93.1 m/s[c]
29°
North pole right ascension
20h 32m[d]
North pole declination
48°[d]
Geometric albedo
0.423[15]
Temperaturemin: 75 K (−198 °C)
max: 250 K (−23 °C)[16]
V[6][17]
5.1[18] to 8.48
3.20[6][15]
Angular diameter
0.70″ to 0.22″

Vesta (minor-planet designation: 4 Vesta) is one of the largest objects in the asteroid belt, with a mean diameter of 525 kilometres (326 mi).[10] It was discovered by the German astronomer Heinrich Wilhelm Matthias Olbers on 29 March 1807[6] and is named after Vesta, the virgin goddess of home and hearth from Roman mythology.[19]

Vesta is thought to be the second-largest asteroid, both by mass and by volume, after the dwarf planet Ceres.[20][21][22] Measurements give it a nominal volume only slightly larger than that of Pallas (about 5% greater), but it is 25% to 30% more massive. It constitutes an estimated 9% of the mass of the asteroid belt.[23] Vesta is the only known remaining rocky protoplanet of the kind that formed the terrestrial planets.[24] Numerous fragments of Vesta were ejected by collisions one and two billion years ago that left two enormous craters occupying much of Vesta's southern hemisphere.[25][26] Debris from these events has fallen to Earth as howardite–eucrite–diogenite (HED) meteorites, which have been a rich source of information about Vesta.[27][28][29]

Vesta is the brightest asteroid visible from Earth. It is regularly as bright as magnitude 5.1,[18] at which times it is faintly visible to the naked eye. Its maximum distance from the Sun is slightly greater than the minimum distance of Ceres from the Sun,[e] although its orbit lies entirely within that of Ceres.[30]

NASA's Dawn spacecraft entered orbit around Vesta on 16 July 2011 for a one-year exploration and left the orbit of Vesta on 5 September 2012[31] en route to its final destination, Ceres. Researchers continue to examine data collected by Dawn for additional insights into the formation and history of Vesta.[32][33]

  1. ^ "Vesta". Dictionary.com Unabridged (Online). n.d.
  2. ^ Cite error: The named reference PlanetarySociety was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference DawnMissionSearch was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference MPS was invoked but never defined (see the help page).
  5. ^ E.g in Meteoritics & planetary science (volume 42, issues 6–8, 2007) and Origin and evolution of Earth (National Research Council et al., 2008).
  6. ^ a b c d e f Cite error: The named reference jpldata was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Souami_Souchay_2012 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Horizons2021 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Vesta-POE was invoked but never defined (see the help page).
  10. ^ a b c d e f Cite error: The named reference Russell2012 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference surfacecalc was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Konopliv2014103 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference lc was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference SkyLive4Vesta was invoked but never defined (see the help page).
  15. ^ a b Cite error: The named reference iras was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference Mueller01 was invoked but never defined (see the help page).
  17. ^ Cite error: The named reference tax was invoked but never defined (see the help page).
  18. ^ a b Cite error: The named reference Pasachoff1983 was invoked but never defined (see the help page).
  19. ^ "In Depth - 4 Vesta". NASA Solar System Exploration. 10 November 2017. Retrieved 13 December 2022.
  20. ^ Cite error: The named reference NASADawnMission was invoked but never defined (see the help page).
  21. ^ Cite error: The named reference CambridgeSS was invoked but never defined (see the help page).
  22. ^ Cite error: The named reference Russell2011 was invoked but never defined (see the help page).
  23. ^ Cite error: The named reference Pitjeva05 was invoked but never defined (see the help page).
  24. ^ Cite error: The named reference lastofkind was invoked but never defined (see the help page).
  25. ^ Cite error: The named reference Jutzi2013 was invoked but never defined (see the help page).
  26. ^ Cite error: The named reference Cook2014a was invoked but never defined (see the help page).
  27. ^ Cite error: The named reference McSween2013 was invoked but never defined (see the help page).
  28. ^ Cite error: The named reference Kelley2003 was invoked but never defined (see the help page).
  29. ^ Cite error: The named reference nasa2011-vesta was invoked but never defined (see the help page).
  30. ^ Cite error: The named reference GravitySim was invoked but never defined (see the help page).
  31. ^ Cite error: The named reference Dawnstatus was invoked but never defined (see the help page).
  32. ^ Cite error: The named reference Ammannito2013 was invoked but never defined (see the help page).
  33. ^ Cite error: The named reference Cook2014b was invoked but never defined (see the help page).


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