An extrasolar object () is an
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. In astronomy, the terms ''object'' and ''body'' are of ...
that exists outside the
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...
. It is not applied to stars, or any other celestial object that is larger than a star or the Solar System, such as a
galaxy
A galaxy is a Physical system, system of stars, stellar remnants, interstellar medium, interstellar gas, cosmic dust, dust, and dark matter bound together by gravity. The word is derived from the Ancient Greek, Greek ' (), literally 'milky', ...
. The terms for extrasolar examples of Solar System bodies are:
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Extrasolar planet
An exoplanet or extrasolar planet is a planet outside the Solar System. The first confirmed detection of an exoplanet was in 1992 around a pulsar, and the first detection around a main-sequence star was in 1995. A different planet, first detect ...
, also called an "exoplanet"
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Extrasolar moon, also called an "exomoon"
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Exocomet, an extrasolar comet
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Exoasteroid, an extrasolar asteroid
Some Solar System object classes, such as
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 ...
s,
dwarf planet
A dwarf planet is a small planetary-mass object that is in direct orbit around the Sun, massive enough to be hydrostatic equilibrium, gravitationally rounded, but insufficient to achieve clearing the neighbourhood, orbital dominance like the ...
s and
Trans-Neptunian objects have not been detected outside the Solar System.
See also
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Extraterrestrial, referring to objects or phenomena existing within the Solar System, but not on Earth
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Extragalactic astronomy
Extragalactic astronomy is the branch of astronomy concerned with objects outside the Milky Way galaxy. In other words, it is the study of all astronomical objects which are not covered by galactic astronomy.
The closest objects in extragalactic ...
, the study of objects outside the Milky Way Galaxy
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Interstellar object
An interstellar object is an astronomical object in interstellar space that is not gravitationally bound to a star. Applicable objects include asteroids, comets, and rogue planets, but not a star or stellar remnant.
This term can also be appli ...
, an object that has traveled through interstellar space, such as
ʻOumuamua
Oumuamua is the first confirmed interstellar object detected passing through the Solar System. Naming of comets#Current system, Formally designated 1I/2017 U1, it was discovered by Robert Weryk using the Pan-STARRS telescope at Haleakalā O ...
, the first known example
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List of artificial objects leaving the Solar System
Several space probes and the upper stages of their launch vehicles are leaving the Solar System, all of which were launched by NASA. Three of the probes, ''Voyager 1'', ''Voyager 2'', and ''New Horizons,'' are still functioning and are regula ...
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Planetary system
A planetary system is a set of gravity, gravitationally bound non-stellar Astronomical object, bodies in or out of orbit around a star or star system. Generally speaking, systems with one or more planets constitute a planetary system, although ...
, a set of gravitationally bound non-stellar objects in orbit around a star or star system
* {{Annotated link, Substellar object
Astronomical nomenclature