We measure the extremely long distances between things in space by light years. A light year is the distance that light travels in one Earth year. Light travels at about 300,000 kilometres per second.

For only the third time in recorded history, an interstellar object has crossed into our solar system, creating quite the ...

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

Captured just days after its discovery, the images offer the clearest view yet of this rare visitor from beyond our solar system.

The shortlist for Astronomy Photographer of the Year 2025 features 30 photographs selected from more than 5,800 global ...

NASA's Advanced Composite Solar Sail System (ACS3) will be visible from the ground. Find out when you can see it on the NASA ...

3I/ATLAS, also known as C/2025 N1, is a comet from interstellar space, meaning it originated in another star system and entered our solar system on a one-time flyby. It was first spotted by the ATLAS ...

Astronomers have confirmed the third interstellar object on record is dashing through our solar system. Dubbed 3I/ATLAS, it ...

Solar systems mostly keep to themselves. What’s ours is ours and what’s not is not. Stars are simply too far from each ...

A quiet, glowing gas cloud has been hiding in plain sight not far from Earth. For decades, astronomers have predicted that ...

An object dubbed 3I/ATLAS is only the third interloper from outside the Solar System seen in all of human history.

Officially named 3I/ATLAS, the comet was confirmed as having originated outside of Earth's solar system on July 3, according ...