For over 50 years, Cornell has made astronomical contributions in the ongoing efforts to explore and understand the mysterious inner workings of Earth’s rust-colored neighbor, Mars. In honor of these ...

New reconstructions of 540 million years of climate history show the planet tumbling between icehouse and hothouse states, revealing how rare and vulnerable our temperate moment is. Some 4 billion ...

Gas giants are massive worlds made mostly of hydrogen and helium. They lack solid surfaces, and in our solar system, Jupiter ...

A newly studied solar system breaks the usual planet pattern, raising fresh questions about how rocky and gas planets form.

(Correction: An earlier version of this story misstated how far Pluto is from the sun. The correct number is 3.7 billion miles.) What was discovered in Flagstaff, Arizona, and killed off in Prague? If ...