Usually, what springs to mind when you think of the world’s most expensive substances are gold, silver, and platinum. However ...

As you watch the night sky, streaks of light often flash for a moment, then disappear. These brilliant flashes—called ...

NASA has just premiered Planetary Defenders, offering a fascinating look at the high-stakes work geared toward protecting Earth from any large asteroids discovered coming our way.

How can we successfully collect and return samples from Mercury and Venus to Earth? This is what a recent study presented at the 56th Lunar and Planetary Science Conference hopes to address as a pair ...

Three Tucson scientists are featured in "Planetary Defenders," a new NASA documentary that premieres Wednesday about the effort to track and possibly deflect asteroids endangering Earth.