Astronomical object

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Astronomical objects are significant physical entities, associations or structures which current science has confirmed to exist in space. This does not necessarily mean that more current science will not disprove their existence. Some astronomical objects, such as Themis and Neith are, in light of more recent findings, considered not to exist at all. Others, like Pluto and Ceres, prove to be of an entirely different nature than first expected. In these cases, the scientific community must come to a consensus as to the new status of these objects. Obviously, not all scientists will agree; this gives birth to fringe science. However, fringe science is not always bad science. Some of our most fundamental scientific theories, such as the superstring theory and plate tectonics, were once considered fringe. Even in the mainstream community, new ideas are constantly changing the way we view the universe at large. Astronomical objects thought to exist based on scientific evidence are considered hypothetical.

Astronomical objects can be easily confused with "astronomical bodies." The term "body" indicates a simple object, such as a planet. These terms differ from "celestial objects" and "celestial bodies" only in that the latter terms do not include the Earth. The table below lists the general categories of objects by their location or structure.

Solar system	Extrasolar objects
	Simple objects	Compound objects	Extended objects
Sun Planetary system Planets Mercury Venus Earth Moon Mars satellites Jupiter satellites Saturn satellites Uranus satellites Neptune satellites Dwarf planets Pluto satellites Eris Dysnomia Ceres Asteroids "Vulcanoids" "Apoheles" Near-Earth asteroids "Arjunas" Atens Apollos Amors Mars-crossers Asteroid belt Hungarias Phocaeas Nysas Alindas Hildas Pallas Marias Koronis Eos Themis Griquas Cybeles Thule Trojan asteroids Mars trojans Jupiter trojans Neptune trojans Outer planet crossers Damocloids Centaurs Trans-Neptunian objects Kuiper Belt Plutinos Cubewanos Twotinos Scattered Disk Objects Sedna Comets Oort cloud Meteoroids Meteors Meteor showers	Exoplanets Hot Jupiters Eccentric Jupiters Pulsar planets Hot Neptunes / Super-Earths Transiting planets Rogue / Interstellar planets Hypothetical planet types Chthonian planets Oceanic planets Trojan planets Brown dwarfs Lithium dwarfs Methane dwarfs Sub-brown dwarfs Stars by spectral type Blue stars Blue-white stars White stars Yellow-white stars Yellow stars Orange stars Red stars Peculiar stars Carbon stars C-type stars S-type stars Shell stars Wolf-Rayet stars Peculiar A-type stars Metallic A-type stars Barium stars P Cygni stars Blue stragglers Stars by luminosity class Subdwarf stars Dwarf (Main sequence) stars Subgiant stars Giant stars Bright giant stars Supergiant stars Hypergiant stars Stars by population Population III stars Population II stars Halo stars Thick disk stars Population I stars Stars by stellar evolution Protostars Young stellar objects Main sequence stars Red giant stars Red supergiant stars Blue supergiant stars Wolf-Rayet stars White dwarf stars Neutron stars Variable stars Intrinsic variables Pulsating variables Cepheid variables W Virginis variables Delta Scuti variables RR Lyrae variables Mira variables Semiregular variables Irregular variables Beta Cephei variables Alpha Cygni variables RV Tauri variables Eruptive variables Flare stars T Tauri variables FU Orionis variables R Coronae Borealis variables Luminous blue variables Cataclysmic variables Symbiotic variables Dwarf novae Novae Supernovae Type I supernovae Type II supernovae Hypothetical Collapsars or Hypernovae Extrinsic variables Rotating variables Alpha2 CVn stars Rotating ellipsoidal variables Eclipsing binaries Algol stars, Algol Beta Lyrae stars W Ursae Majoris stars Compact stars White dwarfs Black dwarfs Neutron stars Magnetars Pulsars Hypothetical stars Quark stars Preon stars Black holes Intermediate-mass black holes Supermassive black holes Gamma ray bursts	Planetary systems Star systems Single star systems Solar system Multiple star systems Binary stars Optical binaries Visual binaries Astrometric binaries Spectroscopic binaries Eclipsing binaries Close binaries Detached binaries Semidetached binaries Contact binaries Unresolved binaries X-ray bursters Triple star systems Stellar groupings Star clusters Stellar associations Open clusters Globular clusters Constellations Asterisms Galaxy components Galactic bulges Galactic bars Galactic rings Spiral arms Thin disks Thick disks Galactic halos Galactic coronae Galaxies Galaxies by morphology Spiral galaxies Barred spiral galaxies Lenticular galaxies Elliptical galaxies Ring galaxies Irregular galaxies Galaxies by size Giant diffuse galaxies Giant ellipticals Dwarf galaxies Active galaxies Quasars Blazars Radio galaxies Seyfert galaxies Starburst galaxies Dark galaxies Galaxy clusters Galaxy cluster clouds Superclusters Filaments / Voids	Circumstellar matter Debris disks Interplanetary medium Protoplanetary disks Interstellar medium Nebulae Emission nebulae Planetary nebulae Supernova remnants Plerions H II regions Reflection nebulae Dark nebulae Molecular clouds Bok globules Proplyds H I regions Intergalactic medium Cosmic microwave background radiation Dark matter MACHOs WIMPs Hypothetical Cosmic string Domain wall

[edit] See also

• List of solar system objects
• Lists of astronomical objects
• List of light sources