[ neer-urth ]
/ ˈnɪərˈɜrθ /
a comet or asteroid pushed by the gravitational attraction of nearby planets into an orbit that allows it to enter the earth's orbit and thereby pose a danger of collision. Abbreviation: NEO
When To Capitalize “Earth”When it comes to writing, this common English word confuses many native speakers who aren’t sure whether to use Earth or earth. Why is this an issue? Earth can be either a proper noun or a common noun. In English, proper nouns (nouns which signify a particular person, place, or thing) are capitalized. Following this rule, when Earth is discussed as a specific planet or …
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Science definitions for near-earth object
[ nîr′ûrth′ ]
A comet or asteroid with an orbit or trajectory that comes near Earth's orbit, often drawn into such a path by the gravitational effect of the Earth and other planets. While there is currently no known near-Earth object on a collision course with Earth, collisions with such objects have taken place in the past and may be associated with mass extinctions such as those that took place at the end of the Permian and Cretaceous Periods.
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