Definitions for asteroid
ˈæs təˌrɔɪdas·ter·oid

Princeton's WordNetRate this definition:3.0 / 3 votes

1. asteroidadjective

   any of numerous small celestial bodies composed of rock and metal that move around the sun (mainly between the orbits of Mars and Jupiter)

2. asteroid, star-shapedadjective

   shaped like a star

WiktionaryRate this definition:3.5 / 2 votes

1. asteroidnoun

   A naturally occurring solid object, which is smaller than a planet and is not a comet, that orbits a star

2. asteroidnoun

   In the Solar system, such a body that orbits within the orbit of Jupiter

3. asteroidnoun

   Any member of the taxonomic class Asteroidea; a starfish

4. Etymology: From ἀστεροειδής, from ἀστήρ + εἶδος.

WikipediaRate this definition:0.0 / 0 votes

1. Asteroid

   An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. Of the roughly one million known asteroids the greatest number are located between the orbits of Mars and Jupiter, approximately 2 to 4 AU from the Sun, in the main asteroid belt. Asteroids are generally classified to be of three types: C-type, M-type, and S-type. These were named after and are generally identified with carbonaceous, metallic, and silicaceous compositions, respectively. The size of asteroids varies greatly; the largest, Ceres, is almost 1,000 km (600 mi) across and qualifies as a dwarf planet. The total mass of all the asteroids combined is only 3% that of Earth's Moon. The majority of main belt asteroids follow slightly elliptical, stable orbits, revolving in the same direction as the Earth and taking from three to six years to complete a full circuit of the Sun.Asteroids have been historically observed from Earth; the Galileo spacecraft provided the first close observation of an asteroid. Several dedicated missions to asteroids were subsequently launched by NASA and JAXA, with plans for other missions in progress. NASA's NEAR Shoemaker studied Eros, and Dawn observed Vesta and Ceres. JAXA's missions Hayabusa and Hayabusa2 studied and returned samples of Itokawa and Ryugu, respectively. OSIRIS-REx studied Bennu, collecting a sample in 2020 to be delivered back to Earth in 2023. NASA's Lucy, launched in 2021, will study ten different asteroids, two from the main belt and eight Jupiter trojans. Psyche, scheduled for launch in 2023, will study a metallic asteroid of the same name. Near-Earth asteroids can threaten all life on the planet; an asteroid impact event resulted in the Cretaceous–Paleogene extinction. Different asteroid deflection strategies have been proposed; the Double Asteroid Redirection Test spacecraft, or DART, was launched in 2021 and intentionally impacted Dimorphos in September 2022, successfully altering its orbit by crashing into it.

ChatGPTRate this definition:0.0 / 0 votes

1. asteroid

   An asteroid is a small, rocky celestial body that orbits the sun. They are similar to planets but much smaller in size. Most asteroids are found in the asteroid belt, a region of space located between the orbits of Mars and Jupiter. They are made up of various types of rock and metals and are considered remnants from the early solar system.

Webster DictionaryRate this definition:0.0 / 0 votes

1. Asteroidnoun

   a starlike body; esp. one of the numerous small planets whose orbits lie between those of Mars and Jupiter; -- called also planetoids and minor planets

2. Etymology: [Gr. starlike, starry; 'asth`r star + e'i^dos form: cf. F. astrode. See Aster.]

FreebaseRate this definition:1.0 / 1 vote

1. Asteroid

   Asteroids are minor planets that are not comets, especially those of the inner Solar System. They have also been called planetoids, especially the larger ones. These terms have historically been applied to any astronomical object orbiting the Sun that did not show the disk of a planet and was not observed to have the characteristics of an active comet, but as small objects in the outer Solar System were discovered, their volatile-based surfaces were found to more closely resemble comets, and so were often distinguished from traditional asteroids. Thus the term asteroid has come increasingly to refer specifically to the small bodies of the inner Solar System out to the orbit of Jupiter. They are grouped with the outer bodies—centaurs, Neptune trojans, and trans-Neptunian objects—as minor planets, which is the term preferred in astronomical circles. In this article the term "asteroid" refers to the minor planets of the inner Solar System. There are millions of asteroids, many thought to be the shattered remnants of planetesimals, bodies within the young Sun's solar nebula that never grew large enough to become planets. The large majority of known asteroids orbit in the asteroid belt between the orbits of Mars and Jupiter or co-orbital with Jupiter. However, other orbital families exist with significant populations, including the near-Earth asteroids. Individual asteroids are classified by their characteristic spectra, with the majority falling into three main groups: C-type, S-type, and M-type. These were named after and are generally identified with carbon-rich, stony, and metallic compositions, respectively.

Chambers 20th Century DictionaryRate this definition:0.0 / 0 votes

1. Asteroid

   as′tėr-oid, n. one of the minor planetary bodies revolving between the orbits of Mars and Jupiter.—adj. Asteroid′al. [Gr. astēr, a star, eidos, form.]

Anagrams for asteroid »

1. troiades

How to pronounce asteroid?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

   Australian

   Natasha

   Australian

   Veena

   Indian

   Priya

   Indian

   Neerja

   Indian

   Zira

   US English

   Oliver

   British

   Wendy

   British

   Fred

   US English

   Tessa

   South African

How to say asteroid in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of asteroid in Chaldean Numerology is: 9

2. Pythagorean Numerology

   The numerical value of asteroid in Pythagorean Numerology is: 1

Examples of asteroid in a Sentence

1. Lindley Johnson:

   DART would be NASA's first mission to demonstrate what's known as the kinetic impactor technique -- striking the asteroid to shift its orbit -- to defend against a potential future asteroid impact, this approval step advances the project toward an historic test with a non-threatening small asteroid.

2. William Bottke:

   In a sense, the asteroid belt has been an eyewitness to multiple 'drive-by shootings' from the earliest time in solar system history, by reading the traces left behind, we can use asteroid samplesto tell us who did it, when they did it and how they did it.

3. Charles El Mir:

   It may sound like science fiction but a great deal of research considers asteroid collisions, for example, if there's an asteroid coming at earth, are we better off breaking it into small pieces, or nudging it to go a different direction ? And if the latter, how much force should we hit it with to move it away without causing it to break ?

4. Paul Chodas:

   We should be getting some great radar images of this asteroid, radar would be the key to study the asteroid's surface, give an idea of its shape, whether it has rocks and that kind of stuff on it. It'll be really exciting.

5. Dave Barry:

   What happens if a big asteroid hits Earth ? Judging from realistic simulations involving a sledge hammer and a common laboratory frog, we can assume it will be pretty bad.

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