Sean Raymond

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 Nautilus Members enjoy an ad-free experience. Log in or Join now . Is Earth unique? Once a grand philosophical question, it has, over the past […]

‘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 Nautilus Members enjoy an ad-free experience. Log in or Join now . Our solar system’s first houseguest—at least, the first one we have seen in our midst—is […]

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 Nautilus Members enjoy an ad-free experience. Log in or Join now . When Frank Drake was a boy, […]

Let There Be Moon: Artist’s rendition of the moon-forming impact between Earth and Theia, a proto-planet.Hagai Perets Nautilus Members enjoy an ad-free experience. Log in or Join now . Some marriages are arranged. Some are for love, others for convenience. Some happen as the result of a sextillion-ton collision in space. The Earth and the […]

A couple years ago, I was part of the team that discovered the first Earth-sized planet, Kepler-186f, rotating comfortably in its star’s “habitable zone,” where water can be liquid. Its sun, Kepler 186, is faint and far away from us—and a little colder than we’d like if we were to settle there—but it does have […]

What would our solar system look like if an alien were to spot it from another planet, orbiting a distant star? How improbable would it appear? For the first time in human history, thanks to advances in exoplanet hunting, we can now answer that question. We can even put numbers on it. If that alien […]

There is an unsolved problem I want to tell you about: The case of the missing Trojans. You might be thinking of the mythical horse with soldiers hidden inside. Or maybe you’re thinking of a sports team. Or a type of computer virus, or, let’s be honest, of the condoms. (Note that I said, “Case […]

Ever notice how pretty much all superhero movies are origins stories? Everyone wants to know how Batman and Wolverine and the Hulk became who they are. But there aren’t too many superhero-in-old-age stories out there, with balding, hunchbacked super-oldsters hobbling around assisted-living homes. Nautilus Members enjoy an ad-free experience. Log in or Join now . […]

Imagine that two very similar-looking neighbors undergo a genetic test. The exam shows that the pair’s genetic fingerprints are virtually identical. They feel a flash of shock and excitement. What does this mean? Could they be long-lost twins, separated in a hospital mixup? Nautilus Members enjoy an ad-free experience. Log in or Join now . […]

Jupiter is famous for its Great Red Spot, but the stormy planet may also be responsible for keeping the inner solar system calm.NASA/JPL Nautilus Members enjoy an ad-free experience. Log in or Join now . You are special, just like your parents used to tell you. You are a rare flower, a unique snowflake. Just […]