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 ...

In late 2025, astronomers spotted an interstellar comet making a quick trip through the solar system. 3I/ATLAS was discovered ...

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

Interstellar comet 3I/ATLAS's first reported sighting was on July 1, and it's going to be the closest it's ever been to Earth on Friday. Along the way, it reached several milestones leading up to what ...

The presence of deuterium, an isotope of hydrogen, in 3I/ATLAS suggests the interstellar comet formed in a much colder place before our solar system existed.

A rare comet from another star system is revealing just how different alien solar systems may be from our own.

The interstellar comet 3I/ATLAS was the third object ever discovered in our solar system that originated from another star system. Despite a viral conspiracy theory, NASA officials have repeatedly ...

The interstellar comet 3I/ATLAS changed significantly as it flew by the sun last fall, astronomers have discovered.

Protoplanetary disk. Figure from a computer simulation visualizing the formation of planets (https://svs.gsfc.nasa.gov/12278 ). Photo: NASA/JPL-Caltech. August 22, 2024, Mountain View, CA - An ...

An interstellar comet carries water unlike anything in our solar system, revealing a far colder birthplace and clues about planetary systems ...