Falling sky debris doesn't pose any real threat. But in the nuclear age, asteroids could trigger war sirens.
*Beware of alarmist headlines. The odds are slim when it comes to giant Earth-bound asteroids.
The secret to the origins of life on Earth could be in the dust that's leftover after solar systems form.
There are a million space rocks nearby. Astronomers have only mapped about 9,700 of them.
In order to reach Mars, our astronauts may have to stop by a lassoed astroid first.
You've heard about comets and asteroids in space. What is the different?
If you've ever glanced skyward, you've probably noticed the sheer numbers of stars. Some are tiny, barely visible points. Others radiate strong white light.
Why is the earth round? Why isn't it a cube or a pyramid?
Learn about 24 Themis, one of the largest known asteroids.
If you've been to a cave, you might think that it's cold underground. Nothing could be further from the truth. Learn more on this Moment of Science.