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30942 Helicaon
30942 Helicaon is a Jupiter trojan from the Trojan camp, approximately in diameter. It was discovered on 8 February 1994, by Belgian astronomer Eric Elst at ESO's La Silla Observatory in northern Chile. The dark Jovian asteroid has a long rotation period of 44.8 hours. It was named after the Trojan warrior Helicaon from Greek mythology. Orbit and classification As all Jupiter trojan, ''Helicaon'' is in a 1:1 orbital resonance with Jupiter. It is located in the trailering Trojan camp at the Gas Giant's Lagrangian point, 60 ° behind its orbit . It is also a non- family asteroid of the Jovian background population. It orbits the Sun at a distance of 4.8–5.5 AU once every 11 years and 10 months (4,314 days; semi-major axis of 5.19 AU). Its orbit has an eccentricity of 0.07 and an inclination of 23 ° with respect to the ecliptic. The body's observation arc begins with its official discovery observation at La Silla in February 1994. Naming This mino ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eric Elst
Eric Walter Elst (30 November 1936 – 2 January 2022) was a Belgian astronomer at the Royal Observatory of Belgium in Uccle and a prolific discoverer of asteroids. The Minor Planet Center ranks him among the top 10 discoverers of minor planets with thousands of discoveries made at ESO's La Silla Observatory in northern Chile and at the Rozhen Observatory in Bulgaria during 1986–2009. The minor planet 3936 Elst, a stony Vestian asteroid from the inner regions of the asteroid belt, roughly 6 kilometers in diameter, was named in his honour. Discoveries Elst is credited by the Minor Planet Center with the discovery of 3866 numbered minor planets made between 1986 and 2009. Notable discoveries include 4486 Mithra, a near-Earth and Apollo asteroid, 7968 Elst-Pizarro, which is classified as both asteroid and comet, and more than 25 Jupiter trojans. His discoveries also include: * binary asteroids such as 4492 Debussy and 15268 Wendelinefroger, * Amor asteroids such as 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trojans In Astronomy
In astronomy, a trojan is a small celestial body (mostly asteroids) that shares the orbit of a larger body, remaining in a stable orbit approximately 60° ahead of or behind the main body near one of its Lagrangian points and . Trojans can share the orbits of planets or of large moons. Trojans are one type of co-orbital object. In this arrangement, a star and a planet orbit about their common barycenter, which is close to the center of the star because it is usually much more massive than the orbiting planet. In turn, a much smaller mass than both the star and the planet, located at one of the Lagrangian points of the star–planet system, is subject to a combined gravitational force that acts through this barycenter. Hence the smallest object orbits around the barycenter with the same orbital period as the planet, and the arrangement can remain stable over time. In the Solar System, most known trojans share the orbit of Jupiter. They are divided into the Greek camp at (ah ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minor Planet Center
The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory. Function The Minor Planet Center is the official worldwide organization in charge of collecting observational data for minor planets (such as asteroids), calculating their orbits and publishing this information via the '' Minor Planet Circulars''. Under the auspices of the International Astronomical Union (IAU), it operates at the Smithsonian Astrophysical Observatory, which is part of the Center for Astrophysics along with the Harvard College Observatory. The MPC runs a number of free online services for observers to assist them in observing minor planets and comets. The complete catalogue of minor planet orbits (sometimes referred to as the "Minor Planet Catalogue") may also be freely downloaded. In addition to astrometric data, the MPC collect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laodice (daughter Of Priam)
In Greek mythology, Laodice (; grc, Λαοδίκη, ; "people-justice") was the daughter of Priam of Troy and Hecuba. She was described as the most beautiful of Priam's daughters.Homer, ''Iliad'' 3.123 The ''Iliad'' mentions Laodice as the wife of Helicaon, son of Antenor, although according to Hyginus she was the wife of Telephus, king of Mysia and son of Heracles. Mythology Before the outbreak of the Trojan War, Laodice fell in love with Acamas, son of Theseus, who had come to Troy to try to recover Helen through diplomatic means. She became pregnant and bore him the son Munitus. The later was given to Acamas' grandmother Aethra, who was then a slave to Helen. After the war had ended, Acamas took his son with him. Much later, Munitus was bitten by a snake while hunting with his father in Thrace and died. According to the '' Bibliotheca'' and several other sources, in the night of the fall of Troy Laodice feared she might become one of the captive women and prayed to the god ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Priam
In Greek mythology, Priam (; grc-gre, Πρίαμος, ) was the legendary and last king of Troy during the Trojan War. He was the son of Laomedon. His many children included notable characters such as Hector, Paris, and Cassandra. Etymology Most scholars take the etymology of the name from the Luwian 𒉺𒊑𒀀𒈬𒀀 (Pa-ri-a-mu-a-, or “exceptionally courageous”), attested as the name of a man from Zazlippa, in Kizzuwatna. A similar form is attested transcribed in Greek as ''Paramoas'' near Kaisareia in Cappadocia. Some have identified Priam with the historical figure of Piyama-Radu, a warlord active in the vicinity of Wilusa. However, this identification is disputed, and is highly unlikely, given that he was known in Hittite records as being an ally of the Ahhiyawa against Wilusa. A popular folk etymology derives the name from the Greek verb , meaning 'to buy'. This in turn gives rise to a story of Priam's sister Hesione ransoming his freedom, with a golden veil that A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenor (mythology)
In Greek mythology, Antenor (Ancient Greek: Ἀντήνωρ ''Antḗnōr'') was a counselor to King Priam of Troy during the events of the Trojan War. Description Antenor was described by the chronicler Malalas in his account of the ''Chronography'' as "tall, thin, white, blond, small-eyed, hook-nosed, crafty, cowardly, secure, a story-teller, eloquent". Meanwhile, in the account of Dares the Phrygian, he was illustrated as "...tall, graceful, swift, crafty, and cautious." Family Antenor was variously named as the son of the Dardanian noble Aesyetes by Cleomestra or of Hicetaon. He was the husband of Theano, daughter of Cisseus of Thrace, who bore him at least one daughter, Crino, and numerous sons, including Acamas, Agenor, Antheus, Archelochus, Coön, Demoleon, Eurymachus, Glaucus, Helicaon, Iphidamas, Laodamas, Laodocus, Medon,Virgil, ''Aeneid'' 6.484 Polybus and Thersilochus (most of whom perished during the Trojan War). He was also the father of a bastard son, Pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Mythology
A major branch of classical mythology, Greek mythology is the body of myths originally told by the Ancient Greece, ancient Greeks, and a genre of Ancient Greek folklore. These stories concern the Cosmogony, origin and Cosmology#Metaphysical cosmology, nature of the world, the lives and activities of List of Greek mythological figures, deities, Greek hero cult, heroes, and List of Greek mythological creatures, mythological creatures, and the origins and significance of the ancient Greeks' own cult (religious practice), cult and ritual practices. Modern scholars study the myths to shed light on the religious and political institutions of ancient Greece, and to better understand the nature of myth-making itself. The Greek myths were initially propagated in an oral tradition, oral-poetic tradition most likely by Minoan civilization, Minoan and Mycenaean Greece, Mycenaean singers starting in the 18th century BC; eventually the myths of the heroes of the Trojan War and its after ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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).Press release, IAU 2006 General Assembly: Result of the IAU Resolution votes International Astronomical Union, August 24, 2006. Accessed May 5, 2008. Minor planets include asteroids ( |
Observation Arc
In observational astronomy, the observation arc (or arc length) of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly used in the discovery and tracking of asteroids and comets. Arc length has the greatest influence on the accuracy of an orbit. The number and spacing of intermediate observations has a lesser effect. Short arcs A very short arc leaves a high uncertainty parameter. The object might be in one of many different orbits, at many distances from Earth. In some cases, the initial arc was too short to determine if the object was in orbit around the Earth, or orbiting out in the asteroid belt. With a 1-day observation arc, was thought to be a trans-Neptunian dwarf planet, but is now known to be a 1 km main-belt asteroid. With an observation arc of 3 days, was thought to be a Mars-crossing asteroid that could be a threat to Earth, but was later ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecliptic
The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic against the background of stars. The ecliptic is an important reference plane and is the basis of the ecliptic coordinate system. Sun's apparent motion The ecliptic is the apparent path of the Sun throughout the course of a year. Because Earth takes one year to orbit the Sun, the apparent position of the Sun takes one year to make a complete circuit of the ecliptic. With slightly more than 365 days in one year, the Sun moves a little less than 1° eastward every day. This small difference in the Sun's position against the stars causes any particular spot on Earth's surface to catch up with (and stand directly north or south of) the Sun about four minutes later each day than it would if Earth did not orbit; a day on Earth is therefore 24 hours ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Inclination
Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Earth directly above the Equator, the plane of the satellite's orbit is the same as the Earth's equatorial plane, and the satellite's orbital inclination is 0°. The general case for a circular orbit is that it is tilted, spending half an orbit over the northern hemisphere and half over the southern. If the orbit swung between 20° north latitude and 20° south latitude, then its orbital inclination would be 20°. Orbits The inclination is one of the six orbital elements describing the shape and orientation of a celestial orbit. It is the angle between the orbital plane and the plane of reference, normally stated in degrees. For a satellite orbiting a planet, the plane of reference is usually the plane containing the planet's equator. For pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Eccentricity
In astrodynamics, the orbital eccentricity of an astronomical object is a dimensionless parameter that determines the amount by which its orbit around another body deviates from a perfect circle. A value of 0 is a circular orbit, values between 0 and 1 form an elliptic orbit, 1 is a parabolic escape orbit (or capture orbit), and greater than 1 is a hyperbola. The term derives its name from the parameters of conic sections, as every Kepler orbit is a conic section. It is normally used for the isolated two-body problem, but extensions exist for objects following a rosette orbit through the Galaxy. Definition In a two-body problem with inverse-square-law force, every orbit is a Kepler orbit. The eccentricity of this Kepler orbit is a non-negative number that defines its shape. The eccentricity may take the following values: * circular orbit: ''e'' = 0 * elliptic orbit: 0 < ''e'' < 1 * [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
