Microorganisms have been found in virtually every corner of the Earth, from deep sea volcanoes to the tops of frozen mountains. They've also been discovered high up in the atmosphere — but scientists haven't been entirely sure as to nature and extent of these elusive high-altitude organisms. Now, new research suggests…

When astronauts from the Apollo 17 mission landed on the Moon in 1972, one of their mission objectives was to analyze the tenuous atmosphere using the Lunar Atmosphere Composition Experiment, a mass spectrometer (with a shape and appearance weirdly reminiscent of a modern day printer/scanner combo) designed to detect…

Fifty miles overhead, higher than any other formation in our planet's atmosphere, is where you'll find one of the most enigmatic classes of cloud ever observed. They're called noctilucent clouds, and they're some of the most poorly understood meteorological phenomena on Earth.

Dinosaurs once ruled the Earth — but now it appears they ruled in Hell. Ancient charcoal deposits suggest wildfires ran rampant throughout the Cretaceous period, meaning dinosaurs had to spend 80 million years looking out for the next inferno.

Let's imagine that you and a friend could converse on the planet Venus — without having to worry about the lack of oxygen, crushing pressure, and beyond boiling temperatures. Your friend would sound so different that you'd actually see her differently.

2.5 billion years ago, the Sun was basically invisible from the Earth's surface. Microbes in the oceans pumped methane into the atmosphere, creating a giant cloud of smog that covered the entire planet. Yes, the whole world turned into LA.

That's not photoshop; that's an actual cloud hovering inside an actual room. Artist Berndnaut Smilde merges art and science to create small man-made clouds that exist — albeit for just a moment — indoors.

The first, moss-like plants emerged on land about 470 million years ago. In just 25 million years, they stripped the planet of vital minerals, wrecked Earth's carbon cycle, started an ice age, and caused a mass extinction of marine life.

Last week, we learned that an ozone hole had formed above the North Pole for the first time ever. But what exactly is an ozone hole, why are they so dangerous, and what can we do to fix them?

A hole in Earth's protective ozone layer above the Antarctic has become an annual event for the last 25 years, greatly increasing the South Pole's exposure to ultraviolet rays. Now, the same thing is happening above the Arctic Circle.