How big is the universe? In this video, we embark on a journey from our solar system to the edge of the observable cosmos.

On its record-breaking pass by the Sun late last year, the Johns Hopkins APL-built Parker Solar Probe captured stunning ...

New findings about interstellar comet 3I/ATLAS reveal its surprising size, possible thick disk origin, and what makes it ...

Just the third-ever confirmed interstellar object has been detected in our solar system. Here's what we know. (Spoiler: It's ...

Interstellar objects are visitors from solar systems beyond our own, and the third ever such object, known as 3I/ATLAS, has ...

A team of researchers from Ca' Foscari University of Venice and the Universidad Autónoma de Madrid has developed a ...

Astronomers have just discovered what might be the oldest comet ever seen by humanity—an ancient visitor that predates our solar system by billions of years. This interstellar object, named 3I/ATLAS, ...

Researchers at Oxford have discovered that comet 3I/ATLAS may be over 7 billion years old, making it the oldest one we've ...

An "interstellar object" is speeding toward the inner solar system, where Earth is located, astronomers have confirmed.

This new dwarf planet may exist at the edge of the solar system, possibly disproving Planet Nine's existence. This is the story of that newly encountered planet.

Our solar system may have a ninth planet after all, following the declassification of Pluto nearly two decades ago, researchers say.