3I/ATLAS is an interstellar comet from beyond our solar system. It is the third known object of its kind to pass through the solar system.
3I/ATLAS is an interstellar comet, meaning it originated beyond our solar system. Astronomers classified it as interstellar because its hyperbolic trajectory does not form a closed orbit around the Sun. It is the third known interstellar object to pass through our solar system, after 1I/‘Oumuamua and 2I/Borisov.
The object was first observed on July 1, 2025, by the ATLAS survey telescope in Río Hurtado, Chile. After its identification as the third confirmed interstellar comet, it was given the official name 3I/ATLAS. NASA and the European Space Agency describe it as active, with an icy nucleus surrounded by a coma of gas and dust. The Hubble Space Telescope observed it on July 21, 2025, and reported a teardrop-shaped envelope of dust around the nucleus.
NASA said 3I/ATLAS poses no threat to Earth and will continue out of the solar system, never to return. Various observatories and instruments have been used to observe it, including Hubble, Webb, TESS, PUNCH, SOHO, and STEREO.
It is an interstellar comet that originated beyond our solar system. It is the third of its kind confirmed to pass through our solar system.
Its hyperbolic trajectory does not form a closed orbit around the Sun, indicating that the object is not bound to the Sun in a fixed orbit.
According to NASA, 3I/ATLAS poses no threat to Earth.
According to NASA, the comet will leave the solar system and will not return.