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Lists of astronomical objects. Selection of astronomical bodies and objects: Moon Mimas and Ida, an asteroid with its own moon, Dactyl. Comet Lovejoy and Jupiter, a giant gas planet. The Sun; Sirius A with Sirius B, a white dwarf; the Crab Nebula, a remnant supernova. A black hole (artist concept); Vela Pulsar, a rotating neutron star.
The branch of astronomy that studies objects and phenomena outside of the Milky Way galaxy, i.e. all objects not covered by galactic astronomy. extrasolar object Any astronomical object that exists outside the Solar System. The term is generally not applied to stars or any objects larger than a star or the Solar System itself, such as galaxies.
Astronomical object. An astronomical object, celestial object, stellar object or heavenly body is a naturally occurring physical entity, association, or structure that exists within the observable universe. [1] In astronomy, the terms object and body are often used interchangeably. However, an astronomical body or celestial body is a single ...
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. Mercury-crossing minor planets. Venus. Venus-crossing minor planets.
Astronomical naming conventions. In ancient times, only the Sun and Moon, a few stars, and the most easily visible planets had names. Over the last few hundred years, the number of identified astronomical objects has risen from hundreds to over a billion, and more are discovered every year. Astronomers need to be able to assign systematic ...
The New General Catalogue of Nebulae and Clusters of Stars (abbreviated NGC) is an astronomical catalogue of deep-sky objects compiled by John Louis Emil Dreyer in 1888. The NGC contains 7,840 objects, including galaxies, star clusters and emission nebulae. Dreyer published two supplements to the NGC in 1895 and 1908, known as the Index ...
The ecliptic or ecliptic plane is the orbital plane of Earth around the Sun. [1][2][a] 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. [3] The ecliptic is an important reference plane and is the basis of ...
Only a tiny minority of known stars have proper names; all others have only designations from various catalogues or lists, or no identifier at all. Hipparchus in the 2nd century BC enumerated about 850 naked-eye stars. Johann Bayer in 1603 listed about twice this number. Only in the 19th century did star catalogues list the naked-eye stars ...