Planetary Defense By the Numbers: May 2021

Planetary Defense By the Numbers: May 2021

How many near-Earth objects have been found thus far? How big are they? Are there any left to discover? Find out the answers to these questions and more in this month's Planetary Defense: By the Numbers video.

Near-Earth objects (NEOs) are asteroids and comets that orbit the Sun and come within 30 million miles of Earth’s orbit. While many NEOs have been found and closely studied, NASA’s Planetary Defense Coordination Office was established to manage the agency’s ongoing efforts to find, track, study, and if necessary, lead efforts to mitigate a potentially hazardous NEO that could pose a potential impact threat to Earth.