Apollo asteroid
An Apollo asteroid is a near-Earth asteroid whose orbit crosses Earth's and is larger than Earth's orbit.
An Apollo asteroid is a near-Earth asteroid with a semi-major axis greater than 1 astronomical unit and a closest distance to the Sun of less than about 1.017 astronomical units, Earth's farthest distance from the Sun. In other words, its orbit is larger than Earth's but dips inside it, crossing our path.
The group is named after 1862 Apollo, discovered in 1932 by the German astronomer Karl Reinmuth. Apollos are the largest group of near-Earth asteroids, making up more than half of those known. Bennu, Ryugu and Itokawa are all Apollos, and so are the meteoroids of most observed meteorite falls.
Because their orbits cross ours, Apollos are the main group from which an impact could come. Most potentially hazardous asteroids are Apollos. However, crossing orbits do not mean a collision is likely: both bodies must reach the crossing point at the same time, which is extremely rare.
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