Today, we accept the notion that enormous rocks exist within our solar system and that some of them fall to Earth. A little over 200 years ago, though, this idea garnered skepticism and ridicule.

A meteorite that escaped from Mars 16 million years ago was found recently in Antarctica. Does it, or doesn't it, hold evidence that proves the existence of life on the red planet?

Astronomer Fritz Zwicky was the first person to conceive of supernovas, neutron stars, dark matter, and gravitational lenses. So why don't more people know his name?

The idea of launching a telescope into orbit was first suggested in 1923, but the idea wasn't realized until nearly 70 years later. Along the way, there were several obstacles and setbacks.

Cosmos, Contact, Icarus and Billions and Billions—from TV and movies to professional journals and best-selling books, Carl Sagan's influence was legendary.

For every visible star in the observable universe, there are nine masses that are invisible and unidentified. Learn more about the astronomer who proved the existence of dark matter.

While studying one of Jupiter's moons, Ole Roemer happened upon the first good estimate of the speed of light. Before his 1676 discovery, scientists assumed that light could not be measured.

This Hawaiian tenth-grader followed her interest in the Pacific golden plover to Alaska. The goal of her trip? To learn if the birds deliberately or randomly select the location of their nest cups.

Armed with mug shots of New York's top 20 plant invaders, this junior began an expedition in her backyard. How many of these non-native invasive plants had already gained a foothold?

This Alaskan senior wanted more from her summers than being her parents' research assistant. Travel north of the Arctic Circle, and take a close look at her hands-on—and hand-off—research on foxes.