2867 Šteins
Encyclopedia
2867 Šteins is a small main-belt
Asteroid belt
The asteroid belt is the region of the Solar System located roughly between the orbits of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets...

 asteroid
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...

 that was discovered in 1969 by N. S. Chernykh
Nikolai Stepanovich Chernykh
Nikolay Stepanovich Chernykh was a Soviet and Russian astronomer.Chernykh was born in the city of Usman' in Voronezh Oblast...

. It is named after Kārlis Šteins
Karlis Šteins
Kārlis Šteins was a Latvian and Soviet astronomer and populariser of this science.In 1925 he finished the Riga 2nd Secondary school. In 1929 he started the studies in University of Latvia, the Faculty of Mathematics and Natural Science. In 1934 he graduated from the University of Latvia...

, a Latvia
Latvia
Latvia , officially the Republic of Latvia , is a country in the Baltic region of Northern Europe. It is bordered to the north by Estonia , to the south by Lithuania , to the east by the Russian Federation , to the southeast by Belarus and shares maritime borders to the west with Sweden...

n and Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 astronomer. Šteins was visited by the Rosetta space probe in 2008.

Physical characteristics

A study published in 2006 by astronomers at the European Southern Observatory
European Southern Observatory
The European Southern Observatory is an intergovernmental research organisation for astronomy, supported by fifteen countries...

 showed that Šteins is an E-type asteroid
E-type asteroid
E-type asteroids are asteroids thought to have enstatite achondrite surfaces. They form a large proportion of asteroids inward of the main belt known as Hungaria asteroids, but rapidly become very rare as the main belt proper is entered. There are, however, some that are quite far from the inner...

 with a diameter of approximately 4.6 km. Studying the asteroid before its flyby, the Rosetta space probe showed via a lightcurve analysis that Šteins has a rotation period
Rotation period
The rotation period of an astronomical object is the time it takes to complete one revolution around its axis of rotation relative to the background stars...

 of about six hours, is irregular in shape, and does not have any moon
Asteroid moon
A minor planet moon is an astronomical body that orbits a minor planet as its natural satellite. It is thought that many asteroids and Kuiper belt objects may possess moons, in some cases quite substantial in size...

s.

After the Rosetta flyby, the ESA described Šteins as 'a diamond in the sky', as it has a wide body that tapers into a point. The wide section is dominated by a large crater (2.1 km diameter), which surprised scientists, who were amazed the asteroid survived such an impact. The photographs of Šteins taken by Rosetta allowed scientists to determine that the asteroid has dimensions of 6.67 x 5.81 x 4.47 km, which equates to a mean diameter of 5.3 km.

Flyby

On September 5, 2008, the Rosetta space probe flew by Šteins at a distance of 800 kilometres and a relatively slow speed of 8.6 kilometres per second. Despite the short duration of this encounter (approximately 7 minutes in total), a great number of data could be obtained by the 15 scientific instruments operating on-board the Rosetta spacecraft. This was the first of two planned asteroid flybys performed by the probe, the second being to the much larger 21 Lutetia
21 Lutetia
21 Lutetia is a large main-belt asteroid of an unusual spectral type. It measures about 100 kilometers in diameter . It was discovered in 1852 by Hermann Goldschmidt, and is named after Lutetia, the Latin name for Paris....

 in 2010. The timing of the fly-by meant that the asteroid was illuminated by the sun from the perspective of the spacecraft, making the transmitted images clear and concise. European Space Operations Centre
European Space Operations Centre
The European Space Operations Centre is responsible for controlling ESA satellites and space probes. The centre is located in Darmstadt, Germany. It is Mission Control for most of the space projects of the ESA. Since its creation in 1967, the centre has operated 60 European space missions...

 streamed a press conference on Šteins later that day.

See also

  • Aubrite
    Aubrite
    Aubrites are meteorites named for Aubres, a small achondrite meteorite that fell near Nyons, France, in 1836. They are primarily composed of the orthopyroxene enstatite, and are often called enstatite achondrites...

  • Hungaria family
    Hungaria family
    The Hungaria asteroids are a group of asteroids in the asteroid belt that orbit the Sun between 1.78 and 2.00 AU. The asteroids typically have a low eccentricity and an inclination of 16 to 34 degrees....

  • (144898) 2004 VD17
    (144898) 2004 VD17
    -External links:* *...

  • 64 Angelina
    64 Angelina
    64 Angelina is a medium-sized main belt E-type asteroid discovered in 1861. It is an unusually bright form of E-type asteroid.-Discovery and naming:...

  • 3103 Eger
    3103 Eger
    3103 Eger is an Apollo and Mars-crosser asteroid that was discovered in 1982, by Miklós Lovas. It was named after the city of Eger, Hungary.It makes eight approaches to Earth less than in the 20th and 21st centuries. The last close approach was in August 2006 at...

  • 434 Hungaria
    434 Hungaria
    434 Hungaria is a relatively small inner Main belt asteroid. It is classified as an E-type asteroid. It is the namesake for Hungaria asteroids which orbit the sun on the inside of the 1:4 Kirkwood gap, standing out of the core of the main belt....

  • 44 Nysa
    44 Nysa
    44 Nysa is a large and very bright main-belt asteroid, and the brightest member of the Nysian asteroid family. It is classified as a rare class E asteroid and is probably the largest of this type .-Discovery:...

  • 55 Pandora
    55 Pandora
    55 Pandora is a fairly large and very bright main belt asteroid. Pandora was discovered by George Mary Searle on September 10, 1858 from the Dudley Observatory near Albany, NY. It was his first and only asteroid discovery....


External links




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