Hot on the tail of Quadrantid meteor showerAnother sight in the sky is about to arrive: comet Atlas C/2024 G3, which will reach perihelion, the point in its orbit closest to the sun, on January 13. On the same day, we will also see it at its closest point to the Sun. pointed toward Earth, and it could become the brightest comet of 2025, in a year in which no other comets are likely to be visible to the naked eye. Here’s everything you need to know.
C/2024 G3 was discovered on April 5, 2024 by the Asteroid Last Impact Warning System (Atlas), a network of telescopes that scans space for asteroids that could impact Earth. The comet comes from Oort Cloudan isolated region at the outer edge of the solar system that is believed to contain the remains of the materials that formed the solar system’s planets.
When comet C/2024 G3 reaches perihelion, it will be just 13.5 million kilometers from the sun. For context, Mercury, the closest planet to the sun, orbits the star at a distance of 47 million kilometers. According to the latest calculations reported by the Planetary SocietyC/2024 G3 could reach a brightness of magnitude –4.5, about the same as Venus, and would likely be visible to the naked eye for people in the southern hemisphere.
The comet’s unusually close journey to the sun, however, raises questions about its survival. Its orbital trajectory suggests that it is a dynamically old comet and that this is not its first trip around the sun. In fact, its last approach is estimated to have been around 160,000 years ago, meaning it may have already survived a close passage. “It will be very hot and may not survive,” says Nick James, director of the comet section of the British Astronomical Association. “But if so, it could be an impressive object in the southern hemisphere evening sky after perihelion.”
How to observe the comet
If it survives unscathed, the comet will be visible in the western southern hemisphere just after sunset on January 13. The comet’s orbital configuration makes it difficult to observe for those in the northern hemisphere: it will appear very low in the sky just after sunset or before sunrise, but may be obscured by dusk .
The comet’s proximity to the sun means identifying it could be dangerous, and James says C/2024 G3 “should only be observed if you are an experienced observer.” Looking directly at the sun without protective equipment can cause permanent eye damage.
There will also be interference from the light of the moon, which will be in its waning phases, which could make observation more difficult. Observing the comet with the naked eye in the southern hemisphere might be possible, but binoculars or a telescope might be needed.
Those who don’t want to miss the show will be able to follow the comet in images from the Solar and heliospheric observatory Lasco C3 coronagraph, or consult the IAU Minor Planet Center or the Comet observation (COBS) database.
This story was originally published on WIRED Italy and was translated from Italian.
