If it is a galaxy, it would be the oldest known galaxy in the cosmos, but it could also be a brown dwarf or an early black hole.

Time is running short for scientists hoping to collect data from 3I/Atlas, a massive interstellar object hurtling away from the Sun.

Need a refresher about 3I/ATLAS? Here's everything to know about the interstellar object, including when the latest ...

A new analysis of our solar system’s interstellar interloper, 3I/ATLAS, reveals that it’s spewing huge amounts of water — and astronomers can’t immediately explain why. The object, which is widely ...

The interstellar comet 3I/ATLAS is barreling toward its closest point to the sun as perihelion looms on Oct. 29. How different will it look when it reappears on the other side?

From the balcony of his family’s downtown London, Ontario apartment, five-year-old Siddharth Patel would spend nights gazing ...

The interstellar comet 3I/ATLAS may be out of view of Earth, but orbiters on Mars were able to recently get a look at it.

At first, the dot looked like any other star. Then the astrophysicists switched to polarized light and found themselves looking at an entirely unexpected sight. “Everything else disappeared, even the ...