An experiment to quantify the amount of the universe’s lightest element in Earth’s core suggests that the planet’s water has mostly been here since the beginning ...

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Let me take you on a wild ride to the very edges of our Universe. But it won't be as simple as traveling through space. Because the edges that we’re talking about aren’t in space. They’re in time. The ...

The surface of Earth is finite. We can measure it. If it was expanding, then its size would grow with time. And once again, good ol' Earth helps us understand what the universe might be doing beyond ...

This video shows the habitable zone around the star HD 20794 (in green) and the trajectory of the three planets in the system. Thirty years after the discovery of the first exoplanet, we detected more ...