Near-Earth Object

A Near-Earth Object (NEO) is an asteroid or comet whose orbit brings it close to Earth. Specifically, NEOs are classified as those that come within 1.3 astronomical units (AU) of the Sun, where 1 AU is the average distance between the Earth and the Sun, approximately 93 million miles (150 million kilometers). NEOs are further categorized into two main types:

1. **Near-Earth Asteroids (NEAs)** – These are asteroids that approach Earth’s orbit and can be further divided based on their orbital characteristics into Atens, Apollos, and Amors.

2. **Near-Earth Comets (NECs)** – These are comets with orbits that bring them close to Earth.

The study of NEOs is significant due to the potential risk they pose to Earth, as some may have the trajectory necessary to impact it. Monitoring and tracking NEOs helps in planetary defense strategies aimed at preventing possible catastrophic events resulting from such collisions. Furthermore, NEOs can provide scientific insights into the early solar system’s conditions, as they are often considered remnants of original material that formed the planets.