Amor asteroid
An Amor asteroid is a near-Earth asteroid that approaches Earth's orbit from outside without crossing it.
An Amor asteroid comes closer to the Sun than 1.3 astronomical units but stays outside Earth's orbit, with a closest approach between about 1.017 and 1.3 astronomical units. Most Amors cross the orbit of Mars.
The group is named after 1221 Amor, discovered in 1932 by the Belgian astronomer Eugène Delporte. The best-known Amor is 433 Eros, visited by NEAR Shoemaker, and another is 1036 Ganymed, the largest near-Earth asteroid, about 35 kilometres across.
Amors cannot currently hit Earth, but their orbits change over time because of the gravity of the planets. An Amor today may become an Apollo in the future. That is why astronomers keep monitoring them. Mars-crossing Amors are also possible sources of material that ends up as meteorites after further changes in their orbits.
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