Comet 3I/ATLAS will make its closest approach to Earth on December 19, 2025, and can be watched via the Virtual Telescope Project live stream, scheduled to start at 04:00 UTC on December 19 (23:00 EST on December 18).
Interstellar object 3I/ATLAS (C/2025 N1 ATLAS) will reach its perihelion distance of about 1.36 AU from the Sun on October 29, 2025, marking the midpoint of its one-time passage through the Solar System. The hyperbolic object will be unobservable from Earth during the event but will later pass within 97 million km (60 million miles) of Venus and 54 million km (34 million miles) of Jupiter on its way out of the system.
A coronal mass ejection (CME) launched from the Sun on September 19 is forecast by NASA’s ENLIL model to strike interstellar Comet 3I/ATLAS on September 24 or 25, an extremely rare event that comes as the comet brightens 40-fold and prepares to disappear into the Sun’s glare.
A newly discovered comet, designated SWAN25B, emerged from behind the Sun in early September 2025 and was added to the Minor Planet Center’s Possible Comet Confirmation Page on September 12. The object is currently reported at magnitude 8.3 in MPC data, with independent amateur estimates placing it slightly brighter at magnitude 7.4–7.5. Orbit calculations are still in progress.
Newly-discovered Comet SWAN25F is rapidly brightening and may become visible to the naked eye by late April 2025. Its green coma and long tail are currently visible through telescopes.
Comet C/2024 G3 (Atlas), which made its closest approach to Earth on January 14, 2025, and reached perihelion a day later, is creating spectacular photographic opportunities as it brightens in the night sky. Astronomers and skywatchers in the Southern Hemisphere have reported a visible coma and an extended tail, making it one of the most striking comets of recent years.
Comet ATLAS (C/2024 G3) is rapidly approaching the Sun, with its perihelion expected at 10:15 UTC on January 13, 2025, promising a dazzling spectacle as it brightens to a potential magnitude of -5, twice as bright as Venus. The comet has entered the ESA/NASA LASCO C3 field of view at around 07:00 UTC today.
On September 2, 2023, a coronal mass ejection (CME) launched by our sun hit Comet Nishimura (C/2023 P1), causing a disconnection event and stripping its tail. This encounter occurred while the comet was located about halfway between the orbits of Mercury and Venus.
The discovery of hundreds of giant comets in the outer planetary system over the last two decades means that these objects pose a much greater hazard to life than asteroids, a team of astronomers from Armagh Observatory and the University of Buckingham report. The…
