1221 Amor

Minor planets, or planetoids are minor bodies of the Solar system orbiting the Sun (or of other planetary systems orbiting other stars) that are larger than meteoroids (the largest of which might be taken to be around 10 meters or so across) but smaller than major planets (Mercury having a diameter of about 4880 km). The term minor planet is sometimes used as a synonym for asteroid though this is technically incorrect; asteroids are one group of minor planets, a category which also includes Trans-Neptunian objects and ot ...

Including:

• Minor planet - Groups out to the orbit of Earth
• Minor planet - Groups out to the orbit of Mars
• Minor planet - The main asteroid belt
• Minor planet - Families within the main asteroid belt
• Minor planet - Other groups out to the orbit of Jupiter
• Minor planet - Groups beyond the orbit of Jupiter
• Minor planet - Quasi-satellites and horseshoe objects

Read more here: » Minor planet: Encyclopedia - Minor planet

An asteroid is a small, solid object in our Solar System, orbiting the Sun. An asteroid is an example of a minor planet (or planetoid), which are much smaller than planets. Most asteroids are believed to be remnants of the protoplanetary disc which were not incorporated into planets during the system's formation. Some asteroids have moons. The vast majority of the asteroids are within the main asteroid belt, with elliptical orbits between those of Mars and Jupiter. Asteroid - Definition. The term "as ...

Including:

• Asteroid - Definition
• Asteroid - Asteroids in the solar system
• Asteroid - Asteroid classification
• Asteroid - Orbit groups and families
• Asteroid - Spectral classification
• Asteroid - Asteroid discovery
• Asteroid - Historical discovery methods
• Asteroid - Modern discovery methods
• Asteroid - Latest technology: detecting hazardous asteroids
• Asteroid - Naming asteroids
• Asteroid - The naming format
• Asteroid - Unnamed asteroids
• Asteroid - Sources for names
• Asteroid - Special naming rules
• Asteroid - Asteroid symbols
• Asteroid - Asteroid exploration
• Asteroid - Asteroids in fiction and film

Read more here: » Asteroid: Encyclopedia - Asteroid

Amor has several meanings: Amor ("love") was also an alternate name for Cupid, the Roman god of love. He was equivalent to Eros in Greek mythology. The Amor asteroids are a group of near-Earth asteroids named after the asteroid 1221 Amor, the first such asteroid to be discovered. The Amor was a German car. Other related archives1221 Amor, Amor, Amor asteroids, Cupid, Eros, German, Greek mythology, Roman, car, near-Earth asteroids

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The overwhelming majority of asteroids have orbits lying between the orbits of Mars and Jupiter, roughly between 2 to 4 AU. These couldn't form a planet due to the gravitational influence of Jupiter. Jupiter's gravitational influence, through orbital resonance, clears Kirkwood gaps in the asteroid belt, first recognised by Daniel Kirkwood in 1874. The region with the densest concentration (lying between the Kirkwood gaps at 2.06 and 3.27 AU, with eccentricities below about 0.3, and inclinations smaller than 30°) is often called the M ...

See also:

Minor planet, Minor planet - Groups out to the orbit of Earth, Minor planet - Groups out to the orbit of Mars, Minor planet - The main asteroid belt, Minor planet - Families within the main asteroid belt, Minor planet - Other groups out to the orbit of Jupiter, Minor planet - Groups beyond the orbit of Jupiter, Minor planet - Quasi-satellites and horseshoe objects

Read more here: » Minor planet: Encyclopedia II - Minor planet - The main asteroid belt

Asteroid - Historical discovery methods. Asteroid discovery methods have drastically improved over the past two centuries. In the last years of the 18th century, Baron Franz Xaver von Zach organized a group of 24 astronomers to search the sky for the "missing planet" predicted at about 2.8 AU from the Sun by the Titius-Bode law, partly as a consequence of the discovery, by Sir William Herschel in 1781, of the planet Uranus at the distance "predicted" by the law. This task required that hand-drawn sky chart ...

See also:

Asteroid, Asteroid - Definition, Asteroid - Asteroids in the solar system, Asteroid - Asteroid classification, Asteroid - Orbit groups and families, Asteroid - Spectral classification, Asteroid - Asteroid discovery, Asteroid - Historical discovery methods, Asteroid - Modern discovery methods, Asteroid - Latest technology: detecting hazardous asteroids, Asteroid - Naming asteroids, Asteroid - The naming format, Asteroid - Unnamed asteroids, Asteroid - Sources for names, Asteroid - Special naming rules, Asteroid - Asteroid symbols, Asteroid - Asteroid exploration, Asteroid - Asteroids in fiction and film

Read more here: » Asteroid: Encyclopedia II - Asteroid - Asteroid discovery

There are over 1200 Amor asteroids known today. Under 200 of them are numbered, and over 50 of them are named. Amor asteroid - Subdivisions by semi-major axis. Amor asteroids can be partitioned into four sub-groups, depending on their average distance from the Sun. The Amor I subgroup consists of Amor asteroids whose semi-major axes are in between Earth and Mars. That is, they have a semi-major axis between 1.000 and 1.523 au. Less than one fifth of Amor asteroids belong to this subgroup. Amor I asteroids have lower ecce ...

See also:

Amor asteroid, Amor asteroid - Populations, Amor asteroid - Subdivisions by semi-major axis, Amor asteroid - Cross-Populations, Amor asteroid - Well-known Amors, Amor asteroid - External link

Read more here: » Amor asteroid: Encyclopedia II - Amor asteroid - Populations

Some asteroids have unusual horseshoe orbits that are co-orbital with the Earth or some other planet. Examples are 3753 Cruithne and 2002 AA29. The first instance of this type of orbital arrangement was discovered between Saturn's moons Epimetheus and Janus. Sometimes these "horseshoe objects" temporarily become quasi-satellites for a few decades or a few hundred years, before returning to their prior status. Both Earth and Venus are known to have quasi-satellites. Such objects, if associated with Earth or Venus or even hypothetically Mercury are a special class of Aten asteroids ...

See also:

Minor planet, Minor planet - Groups out to the orbit of Earth, Minor planet - Groups out to the orbit of Mars, Minor planet - The main asteroid belt, Minor planet - Families within the main asteroid belt, Minor planet - Other groups out to the orbit of Jupiter, Minor planet - Groups beyond the orbit of Jupiter, Minor planet - Quasi-satellites and horseshoe objects

Read more here: » Minor planet: Encyclopedia II - Minor planet - Quasi-satellites and horseshoe objects

There are a number of more or less distinct asteroid groups outside of the Main Belt, distinguished either by mean distance from the Sun, or particular combinations of several orbital elements: Hungaria asteroids, with a mean orbital radius between 1.78 AU and 2 AU, an eccentricity less than 0.18, and inclination between 16° and 34°. Named after 434 Hungaria, these are just outside Mars orbit, and are possibly attracted by the 2:9 resonance. Phocaea asteroids, with a mean orbital radius between 2.25 AU and 2.5 AU, an ...

See also:

Minor planet, Minor planet - Groups out to the orbit of Earth, Minor planet - Groups out to the orbit of Mars, Minor planet - The main asteroid belt, Minor planet - Families within the main asteroid belt, Minor planet - Other groups out to the orbit of Jupiter, Minor planet - Groups beyond the orbit of Jupiter, Minor planet - Quasi-satellites and horseshoe objects

Read more here: » Minor planet: Encyclopedia II - Minor planet - Other groups out to the orbit of Jupiter

Until the age of space travel, asteroids were merely pinpricks of light in even the largest telescopes and their shapes and terrain remained a mystery. The first close-up photographs of asteroid-like objects were taken in 1971 when the Mariner 9 probe imaged Phobos and Deimos, the two small moons of Mars, which are probably captured asteroids. These images revealed the irregular, potato-like shapes of most asteroids, as did subsequent images from the Voy ...

See also:

Asteroid, Asteroid - Definition, Asteroid - Asteroids in the solar system, Asteroid - Asteroid classification, Asteroid - Orbit groups and families, Asteroid - Spectral classification, Asteroid - Asteroid discovery, Asteroid - Historical discovery methods, Asteroid - Modern discovery methods, Asteroid - Latest technology: detecting hazardous asteroids, Asteroid - Naming asteroids, Asteroid - The naming format, Asteroid - Unnamed asteroids, Asteroid - Sources for names, Asteroid - Special naming rules, Asteroid - Asteroid symbols, Asteroid - Asteroid exploration, Asteroid - Asteroids in fiction and film

Read more here: » Asteroid: Encyclopedia II - Asteroid - Asteroid exploration

Hundreds of thousands of asteroids have been discovered within the solar system, and the present rate of discovery is about 5000 per month. As of November 16, 2005, from a total of 305,224 minor planets with calculated orbits, 120,437 asteroids had been calculated well enough to be given official numbers and 12,712 of these had been officially given trivial names to go along with the numbers (at least 610 of which have names requiring diacritics). The lowest-numbered but unnamed minor planet is (3360) 1981 VA; the ...

See also:

Asteroid, Asteroid - Definition, Asteroid - Asteroids in the solar system, Asteroid - Asteroid classification, Asteroid - Orbit groups and families, Asteroid - Spectral classification, Asteroid - Asteroid discovery, Asteroid - Historical discovery methods, Asteroid - Modern discovery methods, Asteroid - Latest technology: detecting hazardous asteroids, Asteroid - Naming asteroids, Asteroid - The naming format, Asteroid - Unnamed asteroids, Asteroid - Sources for names, Asteroid - Special naming rules, Asteroid - Asteroid symbols, Asteroid - Asteroid exploration, Asteroid - Asteroids in fiction and film

Read more here: » Asteroid: Encyclopedia II - Asteroid - Asteroids in the solar system

Asteroids are commonly classified into groups based on the characteristics of their orbits and on the details of the spectrum of sunlight they reflect. Asteroid - Orbit groups and families. Many asteroids have been placed in groups and families based on their orbital characteristics. It is customary to name a group of asteroids after the first member of that group to be discovered. Groups are relatively loose dynamical associations, whereas families are much "tighter" and result from the catastrophic break ...

See also:

Asteroid, Asteroid - Definition, Asteroid - Asteroids in the solar system, Asteroid - Asteroid classification, Asteroid - Orbit groups and families, Asteroid - Spectral classification, Asteroid - Asteroid discovery, Asteroid - Historical discovery methods, Asteroid - Modern discovery methods, Asteroid - Latest technology: detecting hazardous asteroids, Asteroid - Naming asteroids, Asteroid - The naming format, Asteroid - Unnamed asteroids, Asteroid - Sources for names, Asteroid - Special naming rules, Asteroid - Asteroid symbols, Asteroid - Asteroid exploration, Asteroid - Asteroids in fiction and film

Read more here: » Asteroid: Encyclopedia II - Asteroid - Asteroid classification

Asteroid - The naming format. Newly discovered asteroids are given a provisional designation consisting of the year of discovery and an alphanumeric code, such as 2001 FH. When its orbit is confirmed, it is given a number, and later may also be given a name (e.g. 1 Ceres). The formal naming convention uses parentheses around the number (e.g. (433) Eros), however, dropping the parentheses is quite common. Informally, especially when a name is repeated in running text, it is common to drop the number altogether, or to drop it after the first mention. < ...

See also:

Asteroid, Asteroid - Definition, Asteroid - Asteroids in the solar system, Asteroid - Asteroid classification, Asteroid - Orbit groups and families, Asteroid - Spectral classification, Asteroid - Asteroid discovery, Asteroid - Historical discovery methods, Asteroid - Modern discovery methods, Asteroid - Latest technology: detecting hazardous asteroids, Asteroid - Naming asteroids, Asteroid - The naming format, Asteroid - Unnamed asteroids, Asteroid - Sources for names, Asteroid - Special naming rules, Asteroid - Asteroid symbols, Asteroid - Asteroid exploration, Asteroid - Asteroids in fiction and film

Read more here: » Asteroid: Encyclopedia II - Asteroid - Naming asteroids

The first few asteroids discovered were assigned symbols like the ones traditionally used to designate Earth, the Moon, the Sun and planets. The symbols quickly became ungainly, hard to draw and recognise. By the end of 1851 there were 15 known asteroids, each (except one) with its own symbol. The first four's main variants are shown here: 1 Ceres 2 Pallas 3 Juno 4 Vesta Johann Franz Encke made a major change in the Berliner Astronomisches Jahrbuch (BAJ, "Berlin Astronom ...

See also:

Asteroid, Asteroid - Definition, Asteroid - Asteroids in the solar system, Asteroid - Asteroid classification, Asteroid - Orbit groups and families, Asteroid - Spectral classification, Asteroid - Asteroid discovery, Asteroid - Historical discovery methods, Asteroid - Modern discovery methods, Asteroid - Latest technology: detecting hazardous asteroids, Asteroid - Naming asteroids, Asteroid - The naming format, Asteroid - Unnamed asteroids, Asteroid - Sources for names, Asteroid - Special naming rules, Asteroid - Asteroid symbols, Asteroid - Asteroid exploration, Asteroid - Asteroids in fiction and film

Read more here: » Asteroid: Encyclopedia II - Asteroid - Asteroid symbols

The term "asteroid", meaning star-like (from the Greek asteroeides, aster "star" + -eidos "form, shape"), was coined in 1802 by Sir William Herschel shortly after Olbers discovered the second one, 2 Pallas, in late March of the same year, to describe their star-like appearance; the other then-known planets all show discs, by comparison. He also applied that term to the small moons of the giant planets. The first scientific paper to use the word in it ...

See also:

Asteroid, Asteroid - Definition, Asteroid - Asteroids in the solar system, Asteroid - Asteroid classification, Asteroid - Orbit groups and families, Asteroid - Spectral classification, Asteroid - Asteroid discovery, Asteroid - Historical discovery methods, Asteroid - Modern discovery methods, Asteroid - Latest technology: detecting hazardous asteroids, Asteroid - Naming asteroids, Asteroid - The naming format, Asteroid - Unnamed asteroids, Asteroid - Sources for names, Asteroid - Special naming rules, Asteroid - Asteroid symbols, Asteroid - Asteroid exploration, Asteroid - Asteroids in fiction and film

Read more here: » Asteroid: Encyclopedia II - Asteroid - Definition