About 4. 6 billion years ago, the Solar System formed from a cloud of dust and gas collapsing in on itself due to gravity.

How did Earth, alone among the solar system's rocky planets, become the home for life? How, among all this frigid lifelessness, did our planet become warm, hospitable, and life-sustaining? The answer ...

Where did all the water come from? Water, water everywhere. It covers 70 percent of Earth’s surface and earns it the nickname “the blue planet.” And yet… where did it come from? How is it so abundant ...

An iron meteorite from the core of a melted planetesimal (left) and a chondrite meteorite, derived from a ‘primitive’, unmelted planetesimal (right). Researchers have used the chemical fingerprints of ...

The solid inner core at the center of the Earth, surrounded by the outer core, mantle and crust. Here’s why: While it is well known that a material must be at or below its freezing temperature to be ...

How old is Earth? Our planet's age is known from a variety of sources, from rocks on our own planet to ones from the moon. When you purchase through links on our site, we may earn an affiliate ...

The moon is weird. It's completely unlike anything else in the solar system. So how did our planet end up with such a special ...

Between a rock and a green place: Michelle Gehringer studies fossilized life on early Earth to learn more about the evolution of (oxygenic) photosynthesis - the process that makes the oxygen we breath ...

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