Earth-crossing asteroid
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An Earth-Crossing Asteroid (ECA), is an asteroid that is capable of coming very near to the Earth at any point in the future. This is not to be confused with an Earth-crosser asteroid, which has an aphelion greater than Earth's aphelion, and a perihelion less than the Earth's perihelion. A more precise definition of an Earth-Crossing Asteroid is one "whose orbit cross section can intersect the capture cross section of the Earth as a result of secular gravitational perturbations".
| The minor planetsedit |
| Vulcanoids | Near-Earth asteroids | Main belt | Jupiter Trojans | Centaurs | Damocloids | Comets | Trans-Neptunians (Kuiper belt · Scattered disc · Oort cloud) |
| For other objects and regions, see: asteroid groups and families, binary asteroids, asteroid moons and the Solar system For a complete listing, see: List of asteroids. See also Pronunciation of asteroid names and Meanings of asteroid names. |