NASA to Detail Findings on Interstellar Comet 3I/ATLAS November 19

The National Aeronautics and Space Administration (NASA) has scheduled a live briefing for Wednesday, November 19, 2025, at 3 p.m. EST, to release new imagery and scientific data concerning the interstellar comet 3I/ATLAS. The presentation, which will feature findings compiled from various agency space missions, is set to take place at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The event will be broadcast across official channels, including NASA+, the NASA app, the agency's website, its YouTube channel, and Amazon Prime.

Comet 3I/ATLAS, formally designated C/2025 N1 (ATLAS), is the third confirmed object originating from outside the solar system to transit the region. Its interstellar nature was established following its discovery on July 1, 2025, by the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) observatory in Rio Hurtado, Chile. Scientists confirmed its hyperbolic trajectory and high velocity, indicating it is not gravitationally bound to the Sun. Pre-discovery observations date back to June 14, 2025, captured by facilities such as Caltech's Zwicky Transient Facility.

The comet reached its perihelion, or closest approach to the Sun, on October 30, 2025, at a distance of approximately 1.4 astronomical units, or about 130 million miles. During this phase, its speed peaked near 153,000 miles per hour (246,000 kilometers per hour). Although the comet passed within 19 million miles of Mars in early October, NASA has confirmed that 3I/ATLAS poses no threat to Earth, maintaining a minimum separation of about 170 million miles (1.8 astronomical units).

Crucial trajectory data was refined through observations from the European Space Agency's ExoMars Trace Gas Orbiter (TGO) orbiting Mars, which improved the path prediction's accuracy tenfold. NASA assets, including the Hubble Space Telescope, gathered key data, such as an image taken on July 21, 2025, when the comet was 277 million miles away. This observation revealed a teardrop-shaped dust cocoon surrounding the nucleus, leading astronomers to establish an upper limit for the nucleus diameter at 3.5 miles (5.6 kilometers), with lower estimates around 1,000 feet (320 meters).

The forthcoming presentation will specifically showcase imagery and data from the Hubble and James Webb Space Telescopes, supplemented by data from missions such as SPHEREx. Scientists globally, including those at the University of Hawaii who developed the ATLAS survey system, are analyzing the comet's composition and trajectory as of November 18, 2025, to gain insights into materials formed around other stars. The Virtual Telescope Project is also providing a public livestream of the comet on November 19, 2025, beginning at 4:15 a.m. UTC. Media representatives planning to attend the NASA Live event must submit credentials to Molly Wasser via email two hours before the 3 p.m. EST start time, while the public is invited to submit questions using the hashtag #AskNASA.