Astronomers Spot a 7-Billion-Year-Old Interstellar Comet – Could It Be the Oldest Ever Seen?
The ATLAS telescope in Chile detected 3I/ATLAS near Jupiter’s orbit on July 1, 2025, confirming it as the third known interstellar object. The nucleus measures 6–15 miles across and travels at 130,000 mph, with a perihelion expected on October 30 at 1.4 AU from the Sun. It will not come closer to Earth than 1.8 AU. Early observations show a faint coma, and scientists expect a tail to develop as it nears the Sun.