Comet Churyumov–Gerasimenko, officially designated
67P/Churyumov–Gerasimenko, is a
cometA comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...
with a current
orbital periodThe orbital period is the time taken for a given object to make one complete orbit about another object.When mentioned without further qualification in astronomy this refers to the sidereal period of an astronomical object, which is calculated with respect to the stars.There are several kinds of...
of 6.6 years. It is the destination of the
European Space AgencyThe European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...
's
RosettaRosetta is a robotic spacecraft of the European Space Agency on a mission to study the comet 67P/Churyumov–Gerasimenko. Rosetta consists of two main elements: the Rosetta space probe and the Philae lander. The spacecraft was launched on 2 March 2004 on an Ariane 5 rocket and will reach the comet by...
spacecraft mission, launched on March 2, 2004.
Discovery
The comet was discovered by Klim Ivanovich Churyumov, who examined a photograph that had been exposed for periodic comet
32P/Comas Solá32P/Comas Solà is the name of a periodic comet with a current orbital period of 8.8 years.The comet nucleus is estimated to be 8.4 kilometers in diameter.-Discovery:...
by Svetlana Gerasimenko on September 11, 1969 at the Alma-Ata Astrophysical Institute. Churyumov found a cometary object near the edge of the plate, but assumed that this was Comas Solá.
After returning to his home institute in
KievKiev or Kyiv is the capital and the largest city of Ukraine, located in the north central part of the country on the Dnieper River. The population as of the 2001 census was 2,611,300. However, higher numbers have been cited in the press....
, Churyumov examined all the photographic plates more closely. About a month after the photograph was taken (October 22), he discovered that the object could not be Comas Solá, because it was about 1.8 degrees off the expected position. Further scrutiny produced a faint image of Comas Solá at its expected position on the plate, thus proving that the other object was a newly discovered comet.
Observations
As preparation for the Rosetta mission,
Hubble Space TelescopeThe Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation. A 2.4 meter aperture telescope in low Earth orbit, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared...
pictures taken on March 12, 2003, were closely analyzed. An overall 3-D model was constructed and computer generated images created.
Orbital history
Comets are regularly nudged from one orbit to another when they encounter
JupiterJupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
or
SaturnSaturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn is named after the Roman god Saturn, equated to the Greek Cronus , the Babylonian Ninurta and the Hindu Shani. Saturn's astronomical symbol represents the Roman god's sickle.Saturn,...
in close proximity. It has been calculated that before the year 1959 Churyumov–Gerasimenko had perihelion distance of about 2.7
AUAn astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
. In 1959 a close encounter with Jupiter pushed its perihelion distance to about 1.3 AU, where it remains today.
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