Near-earth

NASA is developing a first-ever robotic mission to visit a large near-Earth asteroid and collect a multi-ton boulder from its surface.

Eros, named for the god of love, is a near-Earth asteroid, which often comes close to our planet.

"Phaethon's nature is debated," said Cooke. "It's either a near-Earth asteroid or an extinct comet, sometimes called a rock comet."

The space agency considers objects that pass within 48 million kilometers of our planet a “near-earth” object.

NASA maintains a planetary defense coordination office that keeps track of near-earth objects and plots their courses through space.

NASA’s Center for Near-Earth Object Studies manager Paul Chodas say they believe they have found and tracked about 90% of the near-earth objects that are at least a kilometer wide and could pose a threat to earth.

Astronomers registered 2,958 previously unknown near-Earth asteroids over the course of the year, the most since 1998, the year the U.S. space agency, NASA, began tracking such objects.

The U.S. space agency, NASA, says there are slightly fewer massive, planet-buster asteroids and far fewer mid-sized, city-buster asteroids than previously thought in near-Earth orbit.