asteroid

See also: Asteroid

English

Wikipedia

An asteroid.

Etymology

Borrowing from Ancient Greek ἀστεροειδής (asteroeidēs), from ἀστήρ (astēr, “star”) + εἶδος (eidos, “form”).

Pronunciation

• enPR: ăs'tə-roid", IPA^(key): /ˈæstəroɪd/

Noun

asteroid (plural asteroids)

1. (astronomy) A naturally occurring solid object, which is smaller than a planet and is not a comet, that orbits a star
2. (astronomy) In the Solar system, such a body that orbits within the orbit of Jupiter
   • 2007, Hannu Karttunen et al. editor, Fundamental Astronomy, edition 5, page 131:

     The orbital planes of asteroids, minor bodies that circle the Sun mainly between the orbits of Mars and Jupiter, are often more tilted ...

3. (zoology) Any member of the taxonomic class Asteroidea; a starfish

Usage notes

The term "asteroid" has never been precisely defined. It was coined for objects which looked like stars in a telescope but moved like planets. These were known from the asteroid belt between Mars and Jupiter, and were later found co-orbiting with Jupiter (Trojan asteroids) and within the orbit of Mars. They were naturally distinguished from comets, which did not look at all starlike. Starting in the 1970s, small non-cometary bodies were found outside the orbit of Jupiter, and usage became divided as to whether to call these "asteroids" as well. Some astronomers restrict the term "asteroid" to rocky or rocky-icy bodies with orbits up to Jupiter. They may retain the term planetoid for all small bodies, and thus tend to use it for icy or rocky-icy bodies beyond Jupiter, or may use dedicated words such as centaurs, Kuiper belt objects, transneptunian objects, etc. for the latter. Other astronomers use "asteroid" for all non-cometary bodies smaller than a planet, even large ones such as Sedna and (occasionally) Pluto. However, the distinction between asteroid and comet is an artificial one; many outer "asteroids" would become comets if they ventured nearer the Sun. The official terminology since 2006 has been small Solar System body for any body that orbits the Sun directly and whose shape is not dominated by gravity.

Derived terms

asteroid belt kuiperoid

Related terms

aster asterisk asterism

Translations

astronomy

• Albanian: asteroid
• Arabic: كويكب m (kuwaykib)
• Armenian: աստղանման (astłanman)
• Asturian: asteroide m, planetoide m
• Azeri: asteroid
• Basque: asteroide (eu)
• Belarusian: астэроід m (asteroid)
• Bengali: গ্রহাণু (grôhanu)
• Bulgarian: астероид m (asteroid)
• Catalan: asteroide m, planetoide
• Chinese:

  Mandarin: 小行星 (zh) (xiǎoxíngxīng)

• Czech: asteroid m
• Danish: småplanet, asteroide (da), planetoide
• Dutch: planetoïde (nl), asteroïde (nl)
• Esperanto: asteroido
• Estonian: asteroid (et)
• Faroese: smástjørna f
• Finnish: asteroidi (fi)
• French: astéroïde (fr) m
• Galician: asteroide (gl) m, planetoide (gl) m
• Georgian: ასტეროიდი (asteroidi), მცირე ცთომილები (mc’ire c’t’omilebi)
• German: Asteroid (de) m
• Greek: αστεροειδής (el) m (asteroeidís)
• Hebrew: אסטרואיד (he) m (asteroid)
• Hindi: क्षुद्रग्रह m (kṣudragrah)
• Hungarian: kisbolygó (hu)
• Icelandic: smástirni (is)
• Indonesian: asteroid (id)
• Irish: astaróideach m, mionphláinéad m

• Italian: asteroide (it) m, pianetino (it) m, planetoide m
• Japanese: 小惑星 (ja) (しょうわくせい, shōwakusei), 星状体 (せいじょうたい, seijōtai)
• Kazakh: астероид (asteroïd)
• Khmer: តារាសណ្ឋាន (dara son tharn)
• Korean: 소행성 (ko) (sohaengseong) (小行星 (ko))
• Latvian: asteroīds m
• Lithuanian: asteroidas m
• Navajo: tsé naatʼaʼí
• Norwegian: asteroide
• Persian: ستارک (fa) (sayârak)
• Polish: asteroida (pl) f, planetoida (pl) f
• Portuguese: asteróide (pt) m, planetóide m
• Romanian: asteroid (ro) m, asteroizi pl
• Russian: астероид (ru) m (asteroid), малая планета f (malaja planeta)
• Serbo-Croatian:

  Cyrillic: астероид m

  Roman: asteroid m

• Sindhi: گِرَھِڙِي f (girahirree)
• Slovak: asteroid m
• Slovene: asteroid (sl) m
• Spanish: asteroide (es) m, planetoide m
• Swedish: asteroid (sv) c
• Tagalog: asteroyd, bulalakaw
• Tamil: நுண்கோள் (nuṇkōḷ)
• Thai: ดาวเคราะห์น้อย (daao krór nói)
• Turkish: asteroit
• Ukrainian: астероїд (uk) m (asterojid)
• Urdu: کشودرگرہ m (kṣudragrah)
• Vietnamese: tiểu hành tinh (小行星)

See also

• astroid
• comet
• planetoid

External links

• asteroid in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913
• asteroid in The Century Dictionary, The Century Co., New York, 1911

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Czech

Noun

asteroid m

1. asteroid

See also

• planetka f

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Estonian

Noun

asteroid (^??? please provide the genitive and partitive!)

1. asteroid

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Indonesian

Noun

asteroid

1. asteroid

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Romanian

Noun

asteroid

1. asteroid

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Serbo-Croatian

Noun

asteròīd m (Cyrillic spelling астеро̀ӣд)

1. asteroid

Declension

    declension of asteroid

	singular	plural
nominative	asteròīd	asteroidi
genitive	asteroída	asteroida
dative	asteroidu	asteroidima
accusative	asteroid	asteroide
vocative	asteroide	asteroidi
locative	asteroidu	asteroidima
instrumental	asteroidom	asteroidima

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Slovene

Pronunciation

• IPA^(key): /astɛrɔˈíːt/
• Tonal: asteroȋd

Noun

asteroíd m inan (genitive asteroída, nominative plural asteroídi)

1. asteroid

Declension

Declension of asteroíd (masculine inan., hard)

	singular	dual	plural
nominative	asteroíd	asteroída	asteroídi
accusative	asteroíd	asteroída	asteroíde
genitive	asteroída	asteroídov	asteroídov
dative	asteroídu	asteroídoma	asteroídom
locative	asteroídu	asteroídih	asteroídih
instrumental	asteroídom	asteroídoma	asteroídi

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Swedish

Noun

asteroid c

1. asteroid

Declension

Declension of asteroid

	singular		plural
Common	indefinite	definite	indefinite	definite
nominative
genitive