V-type asteroid
Encyclopedia
The spectra of the V-type asteroids or Vestoids are similar to that of 4 Vesta
4 Vesta
Vesta, formally designated 4 Vesta, is one of the largest asteroids, with a mean diameter of about . It was discovered by Heinrich Wilhelm Olbers on March 29, 1807, and is named after the Roman virgin goddess of home and hearth, Vesta....

, by far the largest asteroid in this class (hence the name).

A large proportion have orbital elements similar to those of 4 Vesta, either close enough to be part of the Vesta family
Vesta family
The Vesta or Vestian family of asteroids is a large and prominent grouping of mostly V-type asteroids in the inner asteroid belt in the vicinity of 4 Vesta...

, or having similar eccentricities and inclination
Inclination
Inclination in general is the angle between a reference plane and another plane or axis of direction.-Orbits:The inclination is one of the six orbital parameters describing the shape and orientation of a celestial orbit...

s but with a semi-major axis
Semi-major axis
The major axis of an ellipse is its longest diameter, a line that runs through the centre and both foci, its ends being at the widest points of the shape...

 lying between about 2.18 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....

 and the 3:1 Kirkwood gap
Kirkwood gap
A Kirkwood gap is a gap or dip in the distribution of main-belt asteroids with semi-major axis , as seen in the histogram below...

 at 2.50 AU. This suggests that most or all of them originated as fragments of Vesta's crust, possibly blasted out by a single very large impact at some point in its history. The enormous southern-hemisphere crater on Vesta is the prime candidate for the impact site.

The V-type asteroids are moderately bright, and rather similar to the more common S-type
S-type asteroid
S-type asteroids are of a stony composition, hence the name. Approximately 17% of asteroids are of this type, making it the second most common after the C-type.-Characteristics:...

, which are also made up of stony
Rock (geology)
In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...

 iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

s and ordinary chondrite
Chondrite
Chondrites are stony meteorites that have not been modified due to melting or differentiation of the parent body. They formed when various types of dust and small grains that were present in the early solar system accreted to form primitive asteroids...

s. This rather rare type of asteroid contains more pyroxene
Pyroxene
The pyroxenes are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. They share a common structure consisting of single chains of silica tetrahedra and they crystallize in the monoclinic and orthorhombic systems...

 than the S-type
S-type asteroid
S-type asteroids are of a stony composition, hence the name. Approximately 17% of asteroids are of this type, making it the second most common after the C-type.-Characteristics:...

.

The electromagnetic spectrum
Electromagnetic spectrum
The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....

 has a very strong absorption feature longward of 0.75 μm, another feature around 1 μm and is very red shortwards of 0.7 µm. The visible wavelength spectrum of the V-type asteroids (including 4 Vesta itself) is similar to the spectra of basaltic achondrite HED meteorite
HED meteorite
HED meteorites are a subgroup of achondrite meteorites. HED stands for "Howardite–Eucrite–Diogenite".These achondrites came from a differentiated parent body and experienced extensive igneous processing not much different from the magmatic rocks found on Earth and for this reason they closely...

s.

A J-type has been suggested for asteroids having a particularly strong 1 μm absorption band similar to diogenite
Diogenite
Diogenites are a subgroup of the HED meteorite group, a type of achondritic stony meteorites.-Origin and composition:Diogenites originates from deep within the crust of the asteroid 4 Vesta, and as such are part of the HED meteorite group...

 meteorites, likely being derived from deeper parts of the crust of 4 Vesta.

Distribution

The vast majority of V-type asteroids are members of the Vesta family along with Vesta itself. There are some Mars-crossers
Mars-crosser asteroid
A Mars-crosser is an asteroid whose orbit crosses that of Mars. The known numbered Mars-crossers are listed here. They include the two numbered Mars trojans 5261 Eureka and ....

 such as 9969 Braille
9969 Braille
9969 Braille is a small Mars-crossing asteroid that orbits the Sun once every 3.58 years. It was discovered in 1992 by astronomers at Palomar observatory and later named after Louis Braille, the inventor of the writing system for the blind...

, and some Near-Earth objects like 3908 Nyx
3908 Nyx
3908 Nyx is an Amor and Mars-crosser asteroid. It was discovered by Hans-Emil Schuster on August 6, 1980, and is named after Nyx, the Greek goddess of the night, after which Pluto's moon Nix is also named...

.

There is also a scattered group of objects in the general vicinity of the Vesta family but not part of it. These include:
  • 809 Lundia
    809 Lundia
    809 Lundia is a small, binary, V-type asteroid orbiting within the Flora family in the Main Belt. It is named after Lund Observatory, Sweden....

     — Orbits within the Flora family
    Flora family
    The Flora family of asteroids is a large grouping of S-type asteroids in the inner main belt, whose origin and properties are relatively poorly understood at present...

     region
  • 956 Elisa
    956 Elisa
    956 Elisa is a V-type asteroid in the Main Belt, orbiting not far from the Vesta family, but not within it. It is, however, probably a fragment of 4 Vesta ejected during an impact. Its rotation period is 3.888 hours.-External links:*...

  • 1459 Magnya
    1459 Magnya
    1459 Magnya is a main-belt asteroid discovered on November 04, 1937 by Grigory Neujmin at Simeiz Observatory. - External links :*...

     — Orbits in the outer asteroid belt, too far from Vesta to be genetically related. May be the remains of a different ancient differentiated body that was shattered long ago.
  • 2113 Ehrdni
    2113 Ehrdni
    2113 Ehrdni is a main-belt asteroid discovered on September 11, 1972 by N. S. Chernykh at the Crimean Astrophysical Observatory.- External links :*...

  • 2442 Corbett
    2442 Corbett
    2442 Corbett is a main-belt asteroid discovered on October 3, 1980 by Vavrova, Z. at Klet.- External links :*...

  • 2566 Kirghizia
    2566 Kirghizia
    2566 Kirghizia is a main-belt asteroid discovered on March 29, 1979 by N. Chernykh at Nauchnyj.- External links :*...

  • 2579 Spartacus
    2579 Spartacus
    2579 Spartacus is a main-belt asteroid discovered on August 14, 1977 by N. Chernykh at Nauchnyj.- External links :*...

     — Contains a significant portion of olivine
    Olivine
    The mineral olivine is a magnesium iron silicate with the formula 2SiO4. It is a common mineral in the Earth's subsurface but weathers quickly on the surface....

    , which may indicate origin deeper within Vesta than other V-types.
  • 2640 Hallstrom
    2640 Hällström
    2640 Hällström is a main belt asteroid with an orbital period of 1355.9467588 days .The asteroid was discovered on March 18, 1941.-References:...

  • 2653 Principia
    2653 Principia
    2653 Principia is a main-belt asteroid discovered on November 4, 1964 by Goethe Link Observatory at Brooklyn. It is named after the ground-breaking Principia Mathematica by Isaac Newton.- External links :*...

  • 2704 Julian Loewe
    2704 Julian Loewe
    2704 Julian Loewe is a main-belt asteroid discovered on June 25, 1979 by E. F. Helin and S. J. Bus at Siding Spring.- External links :*...

  • 2763 Jeans
    2763 Jeans
    2763 Jeans is a main-belt asteroid discovered on July 24, 1982 by E. Bowell at Flagstaff .- External links :*...

  • 2795 Lepage
    2795 Lepage
    2795 Lepage is a main-belt asteroid discovered on December 16, 1979 by H. Debehogne at La Silla.- External links :*...

  • 2851 Harbin
    2851 Harbin
    2851 Harbin is a main-belt asteroid discovered on October 30, 1978 by Purple Mountain Observatory at Nanking.- External links :...

  • 2912 Lapalma
    2912 Lapalma
    2912 Lapalma is a main-belt asteroid discovered on February 18, 1942 by L. Oterma at Turku.- External links :*...

  • 3849 Incidentia
    3849 Incidentia
    3849 Incidentia is a main-belt asteroid discovered on March 31, 1984 by Bowell, E. at Flagstaff .- External links :*...

  • 3850 Peltier
    3850 Peltier
    3850 Peltier is a Main belt asteroid. It was discovered on October 7, 1986 at Anderson Mesa by Ted Bowell who named it in honor of the American astronomer Leslie Peltier....

     — Orbits within the Flora family
    Flora family
    The Flora family of asteroids is a large grouping of S-type asteroids in the inner main belt, whose origin and properties are relatively poorly understood at present...

     region
  • 3869 Norton
    3869 Norton
    3869 Norton is a main-belt asteroid discovered on May 3, 1981 by E. Bowell at Flagstaff .- External links :*...

  • 4188 Kitezh
    4188 Kitezh
    4188 Kitezh is a main-belt asteroid discovered on April 25, 1979 by N. S. Chernykh at Nauchnyj.- External links :*...

  • 4278 Harvey
    4278 Harvey
    4278 Harvey is a main-belt asteroid discovered on September 22, 1982 by Ted Bowell at Flagstaff.-External links:*...

     — Member of Baptistina family
    Baptistina family
    The Baptistina family is an asteroid family that was likely produced by the breakup of an asteroid across 80 million years ago following an impact with a smaller body. The largest presumed remnant of this parent asteroid is 298 Baptistina....

    .
  • 4434 Nikulin
    4434 Nikulin
    4434 Nikulin is a main-belt asteroid discovered on September 8, 1981 by L. V. Zhuravleva at Nauchnyj.- External links :*...

  • 4796 Lewis
    4796 Lewis
    4796 Lewis is a main-belt asteroid discovered on June 3, 1989 by E. F. Helin at Palomar.- External links :*...

  • 4977 Rauthgundis
    4977 Rauthgundis
    4977 Rauthgundis is a main-belt asteroid discovered on September 24, 1960 by Cornelis Johannes van Houten, Ingrid van Houten-Groeneveld and Tom Gehrels at Palomar Observatory.- External links :...

  • 5379 Abehiroshi
    5379 Abehiroshi
    5379 Abehiroshi is a main belt asteroid discovered on April 16, 1991 by S. Otomo and O. Muramatsu at Kiyosato.-References:...

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