Meteoroid

3D-billede af meteoriden 2008 TC3; et 80 tons tungt objekt, ca. 4 meter i diameter, der i 2008 kom ind i Jordens atmosfære, hvor den eksploderede over den Nubiske ørken.

En meteoroid (også kaldet en meteoroide) er et lille stenobjekt i kredsløb om Solen. En meteoroid er mindre end en småplanet (asteroide). Nogle definerer, at et objekt, som er en sten, og mindre end ca. 100 meter i diameter kaldes en meteoroid.


Terminologi

Hvis en meteoroid træder ind i atmosfæren, bliver den kaldt en meteor og hvis den når jordoverfladen, kaldes den en meteorit. Strengt taget rammes Månen og andre atmosfæreløse himmellegemer derfor af meteoroider, selvom nedslagene kaldes for meteorkratere.

Rumdragter og rumfartøjer skal fungere i et miljø uden en beskyttende atmosfære, så de designes til at kunne tåle at blive ramt af mikrometeoroider.

Se også

Kilder/referencer

  1. ↑ Asteroids, Comets, Meteoroids. Near Earth Objects. A Nature's threat from the sky Citat: "...Meteoroids are defined as being solid particles in space larger than 100 µm in size..and smaller than about 10 meters..' [Steel,D.,1997, in 'Near Earth Objects. Annals of New York Academy of Sciences, vol. 822, p.31]..."
  2. ↑ RASC Asteroids FAQ Citat: "...As a general rule an object needs to be one kilometer or larger in diameter to be called an asteroid, although there is no formal agreement on that size. Some astronomers feel that we should include all objects 20 meters or larger in size since an object just 20 meters across travelling at cosmic speeds can invoke serious damage on the earth...Objects smaller than asteroids are called meteoroids..."
  3. ↑ Meteoroids, Asteroids, Comets Citat: "...Meteoroids are rocky bodies about 50 meters across or smaller whose impact with Earth is likely to deliver meteorite samples to the surface, but produce no impact crater...Asteroids, or minor planets, are rocky bodies larger than 50 meters across..."
  4. ↑ The Solar System Citat: "...Our new book contains, for the first time I have found it, some definition of the size break; under 100 meters is a meteoroid and over it is an asteroid..."
  5. ↑ Module 5: Comets, Meteors and Asteroids Arkiveret 13. marts 2007 hos Wayback Machine Citat: "...A meteoroid is much like an asteroid, its only distinction being size. Rocky objects smaller than about 100 metres are generally termed meteoroids..."
  6. ↑ Max. meteoroidestørrelse 1000km?: Asteroids Citat: "...Asteroids on a collision course with Earth are called meteoroids..." og lidt nede i denne side: The Solar System: Minor Bodies Arkiveret 1. september 2006 hos Wayback Machine Citat: "...All known asteroids have diameters less than 1,000 km..."
  7. ↑ Max. meteoroidestørrelse 1000km?: Asteroids, Comets, and Meteoroids Citat: "...A meteoroid is a small object (below 1 km in diameter) in an independent orbit in the solar system..."

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