An Earth trojan is an asteroid that orbits the Sun in the vicinity of the Earth–Sun Lagrange points L4 (leading 60°) or L5 (trailing 60°), thus having an orbit similar to Earth's. Only two Earth trojans have so far been discovered. The name "trojan" was first used in 1906 for the Jupiter trojans, the asteroids that were observed near the Lagrangian points of Jupiter's orbit.
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Earth trojan in the context of Minor planet
According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term minor planet, but that year's meeting reclassified minor planets and comets into dwarf planets and small Solar System bodies (SSSBs). In contrast to the eight official planets of the Solar System, all minor planets fail to clear their orbital neighborhood.
Minor planets include asteroids (near-Earth objects, Earth trojans, Mars trojans, Mars-crossers, main-belt asteroids and Jupiter trojans), as well as distant minor planets (Uranus trojans, Neptune trojans, centaurs and trans-Neptunian objects), most of which reside in the Kuiper belt and the scattered disc. As of October 2025, there are 1,472,966 known objects, divided into 875,150 numbered, with only one of them recognized as a dwarf planet (secured discoveries) and 597,816 unnumbered minor planets, with only five of those officially recognized as a dwarf planet.
View the full Wikipedia page for Minor planetEarth trojan in the context of Wide-field Infrared Survey Explorer
Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy space telescope in the Explorers Program launched in December 2009. WISE discovered thousands of minor planets and numerous star clusters. Its observations also supported the discovery of the first Y-type brown dwarf and Earth trojan asteroid.WISE performed an all-sky astronomical survey with images in 3.4, 4.6, 12 and 22 μm wavelength range bands, over ten months using a 40 cm (16 in) diameter infrared telescope in Earth orbit.
After its solid hydrogen coolant depleted, it was placed in hibernation mode in February 2011.In 2013, NASA reactivated the WISE telescope to search for near-Earth objects (NEO), such as comets and asteroids, that could collide with Earth.
View the full Wikipedia page for Wide-field Infrared Survey ExplorerEarth trojan in the context of Solar System object
The following is a list of Solar System objects by orbit, ordered by increasing distance from the Sun. Most named objects in this list have a diameter of 500 km or more.
- The Sun, a spectral class G2V main-sequence star
- The inner Solar System and the terrestrial planets
- Mercury
- Venus
- Earth
- Mars
- Asteroids in the asteroid belt, between the orbits of Mars and Jupiter
- Ceres, a dwarf planet
- Vesta
- Pallas
- Hygiea
- Europa (asteroid)
- Davida
- Sylvia
- Asteroids number in the hundreds of thousands. For longer lists, see list of exceptional asteroids, list of asteroids, or list of Solar System objects by size.
- A number of smaller groups distinct from the asteroid belt
- The outer Solar System with the giant planets, their satellites, trojan asteroids and some minor planets
- Jupiter
- Saturn
- Uranus
- Rings of Uranus
- Complete list of Uranus's natural satellites
- Uranus trojan (2011 QF99)
- Uranus-crossing minor planets
- Neptune
- Non-trojan minor planets
- Trans-Neptunian objects (beyond the orbit of Neptune)
- Kuiper-belt objects (KBOs)
- Plutinos
- Orcus, a dwarf planet
- Pluto, a dwarf planet
- Complete list of Pluto's natural satellites
- Ixion
- Achlys
- Twotinos
- Cubewanos (classical objects)
- Plutinos
- Scattered-disc objects
- Detached objects
- (612911) 2004 XR190
- 2012 VP113 (possibly inner Oort cloud)
- Sedna, a dwarf planet (possibly inner Oort cloud)
- Oort cloud (hypothetical)
- Kuiper-belt objects (KBOs)
Earth trojan in the context of Minor planets
According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term minor planet, but that year's meeting reclassified minor planets and comets into small Solar System bodies (SSSBs) and dwarf planets, including into the respective categories comets and Pluto, which were generally not considered minor planets. In contrast to the eight official planets of the Solar System, all minor planets fail to clear their orbital neighborhood.
Minor planets include asteroids (near-Earth objects, Earth trojans, Mars trojans, Mars-crossers, main-belt asteroids and Jupiter trojans), as well as distant minor planets (Uranus trojans, Neptune trojans, centaurs and trans-Neptunian objects), most of which reside in the Kuiper belt and the scattered disc. As of October 2025, there are 1,472,966 known objects, divided into 875,150 numbered, with only one of them recognized as a dwarf planet (secured discoveries) and 597,816 unnumbered minor planets, with only five of those officially recognized as a dwarf planet.
View the full Wikipedia page for Minor planetsEarth trojan in the context of 2010 TK7
(706765) 2010 TK7 (provisional designation 2010 TK7) is a sub-kilometer Near-Earth asteroid and the first Earth trojan discovered; it precedes Earth in its orbit around the Sun. Trojan objects are most easily conceived as orbiting at a Lagrangian point, a dynamically stable location (where the combined gravitational force acts through the Sun's and Earth's barycenter) 60 degrees ahead of or behind a massive orbiting body, in a type of 1:1 orbital resonance. In reality, they oscillate around such a point. Such objects had previously been observed in the orbits of Mars, Jupiter, Neptune, and the Saturnian moons Tethys and Dione.
2010 TK7 has a diameter of about 300 meters (1,000 ft). Its path oscillates about the Sun–Earth L4 Lagrangian point (60 degrees ahead of Earth), shuttling between its closest approach to Earth and its closest approach to the L3 point (180 degrees from Earth).
View the full Wikipedia page for 2010 TK7