Sean Raymond

The series of fortunate astrophysical events that gave us Ceres.

First the oceans boil off. Then things really get serious.

Why Earth wasn’t swept into the dustbin of space.

How advanced civilizations could leave us a message of their presence.

New research hints at what makes Earth’s moon special.

Could a comet, not an asteroid, have killed the dinosaurs?

About half of all stars seem to have “super-Earth” planets on orbits closer to their stars than Mercury is to the Sun, but we don’t.Illustration by Vadim Sadovski / Shutterstock Is Earth unique? Once a grand philosophical question, it has, over the past two decades, become, with the discovery of thousands of planets around other […]

Artist’s conception of a hot Eyeball planet. The permanent day side is sun-baked and dry. The permanent night side is covered with ice. In between lies a thin habitat: the ring of life.Illustration by Beau.TheConsortium Imagine a habitable planet orbiting a distant star. You’re probably picturing a variation of Earth. Maybe it’s a little cloudier, […]

‘Oumuamua may be a piece of a torn-apart comet, gravitationally launched into interstellar space, that roamed the galaxy before dropping on our doorstep.ESO / M. Kornmesser / Wikicommons Our solar system’s first houseguest—at least, the first one we have seen in our midst—is a strange one. Scientists have taken to calling it ‘Oumuamua (pronounced “Oh-MOO-ah-MOO-ah”), […]

This system is completely stable—I double-checked with computer simulations. But nature would have a tough time forming this system. If it exists, it could only have been built by a super-advanced civilization.Image by Sean Raymond / planetplanet.net When Frank Drake was a boy, growing up in 1930s Chicago, his parents, observant Baptists, enrolled him in […]