Trojan asteroids

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Trojan asteroids,

or minor planet,
small body orbiting the sun. More than 300,000 asteroids have been identified and cataloged; more than a million are believed to exist in the main belt between Mars and Jupiter, with many more in the Kuiper belt
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 that revolve about the sun in the same orbit as a planet, occupying stable positions (known as Lagrangian points) either about 60° ahead of the planet in the orbit or about 60° behind it. Such asteroids were first discovered (1906) in Jupiter's orbit. In 1990, a similar asteroid, Eureka, was found in the orbit of Mars, and several others have since been discovered. Similar asteroids also have been found in Neptune's orbit since 2001, and a Trojan asteroid in earth's orbit was confirmed in 2011.

The Trojan asteroids represent one possible special solution to the famous three-body problem (see also celestial mechanicscelestial mechanics,
the study of the motions of astronomical bodies as they move under the influence of their mutual gravitation. Celestial mechanics analyzes the orbital motions of planets, dwarf planets, comets, asteroids, and natural and artificial satellites within the
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), with each group forming an equilateral triangle with the planet whose orbit they share and the sun. Some Trojan asteroids are composed of ice and dirt, rather than rock, making it possible that they are captured comets. The first Trojan asteroid discovered was Achilles, observed by the German astronomer Max Wolf; all of Jupiter's Trojan asteroids are named for heroes of the Trojan WarTrojan War,
in Greek mythology, war between the Greeks and the people of Troy. The strife began after the Trojan prince Paris abducted Helen, wife of Menelaus of Sparta. When Menelaus demanded her return, the Trojans refused.
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References in periodicals archive ?
These Trojan asteroids consist of two groups of thousands of asteroids that reside at the same distance from the Sun as Jupiter, but orbiting in front of and behind Jupiter, respectively.
Trojan asteroids are considered remnants of the primordial material from which the solar system also evolved.
28 ( ANI ): Researchers have said that exotic orbit for the largest Trojan asteroid, (624) Hektor-the only one known to possess a moon, may be products of the collision of two icy asteroids.
Trojan asteroids are dark with albedos typically less than 0.05, which implies a broad opposition effect, but they may be icy and have a bright surface component (similar to carbonaceous chondrite meteorites) both of which imply a sharp opposition effect.
They are the only large binary known in the population of ancient bodies referred to as the Trojan asteroids. The two swarms of Trojans orbit at roughly the same distance from the Sun as Jupiter, one swarm orbiting ahead of, and the other trailing, the gas giant.
"Later, Jupiter re-captured the Trojan asteroids, but we don't know where they came from.
The sun, Jupiter, and the so-called Trojan asteroids, for instance, form such a triangle, which rotates about the system's center of mass.
Could the distribution of Trojan asteroids at the Sun-Jupiter Lagrange points be made any more obvious?
Jupiter's 4,000-plus Trojan asteroids - so called because each is named for a hero of the Trojan wars - have the same orbit as Jupiter and are contained in comma-shaped clouds that look remarkably similar to the localized wave packets created in the Rice experiments.
Alternatively, notes Jewitt, the four bodies may rank as the first Trojan asteroids found near Neptune.
NASA has also planned to fund a space mission called Lucy, which will explore Jupiter's Trojan asteroids as part of the undertaking to understand the history of the solar system.