Near-Earth Objects
An NEO's orbit takes it within 1.3 AU of the Sun. The largest known NEO is over 40 km in diameter, but astronomers have found thousands of NEOs with diameters larger than 1 km. Anything smaller is too hard to see.
Hunt the Asteroids
How do we find asteroids?
Make Your Own Impact Crater
Keep Watch on Asteroids
Asteroids are small, rocky objects that orbit the Sun. Most are located between the orbits of Mars and Jupiter. This area of our Solar System is known as the Asteroid Belt.
Ursula Marvin
Occupation: Planetary Geologist
Year born: 1921
Research Areas: Meteorites, Moon Rocks
Solar System Quiz
A solar system consists of a star and the objects that orbit it. A galaxy contains millions of stars and solar systems. But how much do you know about our own Solar System? Take our quiz to find out!