Measurements of this interstellar comet’s molecular makeup show an excess of heavy water molecules that is dramatically different from anything known to have ever formed around our sun ...

When comet 3I/ATLAS swept through the inner solar system in late 2025, it gave astronomers something no interstellar visitor ...

A mysterious comet from beyond our solar system is giving astronomers a rare glimpse into alien worlds — and it may have ...

A newly discovered interstellar object, named 3I/ATLAS, is moving through the solar system fast enough to prove it came from ...

Billions of years ago, while the solar system was still young, a massive object may have drifted into it. It's not a spaceship, but it is an alien visitor in its own right—a colossal interstellar body ...

One million alien visitors from another star system could already be lurking in the solar system. We aren't talking about "little green men" here, however — more "little (and not so little) gray rocks ...

Here’s what you’ll learn when you read this story: Every time an interstellar object comes whizzing into our Solar System, it brings with it a certain intrigue. Where is it from? How did it form? Why ...

Exoplanets are planets that orbit stars other than the sun and thus exist outside the solar system. The word "exoplanet" ...