Data Confirms Interstellar Object 3I/ATLAS Brightened Rapidly Behind the Sun as NASA Spacecraft Tracks Historic Visitor

3I/ATLAS is recognized as an interstellar object because of its extremely hyperbolic path and very high-speed relative to the Solar System, with an orbital eccentricity of 6.137—making the trajectory appear relatively straight rather than curved. Scientists indicate the comet is zooming through our solar system at speeds in excess of 130,000 mph in an unusually flat trajectory.

The speed of the comet, which has the highest velocity ever recorded for a solar system object, suggests it has been traveling for billions of years, gaining momentum from a gravitational slingshot effect as it whips by stars.

The study examining GOES-19 and SOHO data found the comet was distinctly bluer than the sun. Researchers suggest the rapid brightening may result from the cooling effect of sublimating carbon dioxide ice holding water-ice vaporization in check as the object approached the Sun.

The 3I/ATLAS is only the third interstellar object ever recorded, following 1I/’Oumuamua in 2017 and 2I/Borisov in 2019. The NASA-funded ATLAS survey telescope in Rio Hurtado, Chile, first reported observations to the Minor Planet Center on July 1, 2025. NASA has categorized this object as interstellar because of the hyperbolic shape of its orbital path—it does not follow a closed orbital path about the Sun.