Interstellar object 3I/ATLAS forces scientists to rethink impact risks
What's the story
Interstellar objects—space objects that originated outside our solar system and travel through it—could pose a threat to our planet. A recent study led by Darryl Seligman from Michigan State University has explored this potential risk. The research looked at the expected paths and speeds of these celestial bodies, using data linked to M stars (red dwarfs) found throughout the galaxy.
Research findings
Study identifies potential impactors from M stars
The study created around 10 billion sample objects and identified about 10,000 likely impactors. Two main regions of interest were noted: one is the solar apex above our path, which could be a source for more objects. The other is the nearby galactic plane, home to many stars in a wide disk that could also harbor passing bodies.
Seasonal variations
Impact risks could vary with seasons
The study also found that many incoming objects travel at high speeds, but slower ones are more likely to reach Earth. This is because the Sun's gravity can bend their paths more easily. The research revealed that spring brings faster potential impactors for Earth as it faces the solar apex direction during this season.
Risk assessment
Lower latitudes may face higher impact chances
The study also indicated that lower latitudes could face slightly higher impact chances, with a small added risk in the northern hemisphere where most human populations reside today. However, these results are based on M star motions and other stellar motions could create different patterns. The Vera Rubin Observatory will soon test these findings through its Legacy Survey of Space and Time.
Planetary defense exercise
3I/ATLAS: A unique interstellar object
The interstellar comet 3I/ATLAS has recently drawn significant global attention. The United Nations and the International Asteroid Warning Network (IAWN) have confirmed that it is indeed the focus of a structured planetary-defense campaign. This initiative allows experts worldwide to test observation techniques, refine tracking methods, and strengthen global readiness against potential future Near-Earth Object threats.
Training opportunity
3I/ATLAS's interstellar trajectory offers technical challenges
The selection of 3I/ATLAS, formally designated C/2025 N1, is deliberate. Its interstellar trajectory and cometary characteristics offer technical challenges that are invaluable for planetary-defence training. Comets have extended structures such as comae and tails, which complicate accurate astrometric measurements and orbit predictions. By observing 3I/ATLAS, astronomers and planetary-defence experts refine methods for extracting precise astrometry from comet observations.
Campaign schedule
3I/ATLAS observation campaign timeline and goals
The IAWN has announced the official observation window for 3I/ATLAS from November 27, 2025, to January 27, 2026. During this period, observatories worldwide will conduct coordinated measurements to test the full capabilities of the planetary-defence framework. The campaign is a live demonstration of Earth's readiness against cosmic threats and how international cooperation can safeguard our planet.