Near-Earth objects (NEOs)

Definition

Near-Earth Objects (NEOs) are celestial bodies such as asteroids and comets with orbits that bring them close to Earth's orbit. They pose potential threats due to their proximity and size, which can cause significant impact events.

5 Must Know Facts For Your Next Test

1. NEOs include both near-Earth asteroids (NEAs) and near-Earth comets (NECs).
2. The Torino Scale is used to categorize the impact hazard of NEOs.
3. NASA's Planetary Defense Coordination Office monitors NEOs to assess potential collision risks.
4. The majority of NEOs are discovered using ground-based telescopes.
5. Strategies for planetary defense include deflection missions, such as the DART mission, to alter an NEO's course.

Review Questions

• What types of celestial bodies are classified as NEOs?
• What scale is used to categorize the impact hazard of NEOs?
• Which NASA office is responsible for monitoring and assessing the risk of NEOs?

Related terms

Asteroid:

A small rocky body orbiting the Sun, primarily found in the asteroid belt between Mars and Jupiter.

Comet:

An icy celestial object with a nucleus, coma, and tail that becomes more visible as it approaches the Sun.

Planetary Defense:

Efforts and strategies designed to detect, track, and mitigate potential hazards posed by near-Earth objects.