Look Up! A Newly Discovered Green Comet May Be Visible in the Night Sky This Month It may become bright enough to view with the naked eye. Close Credit: Javier Zayas Photography / Getty Images Key Points Comet Lemmon (C/2025 A6), discovered in Arizona earlier this year, will make a once-in-a-lifetime appearance as it passes closest to Earth on October 21, around the same time the Orionids meteor shower peaks.The comet is expected to brighten significantly toward the end of October, possibly becoming visible to the naked eye in dark, non-light-polluted skies around October 31 or November 1.To see the comet during the first half of October, look up in the early morning hours before sunrise. The comet should be visible with binoculars or a telescope. October is shaping up to be an impressive month for stargazing. One of the most impressive celestial events will take place mid-month, when a once-in-a-lifetime comet may be visible in the night sky. Comet Lemmon (C/2025 A6) was discovered by astronomers at the Mt. Lemmon SkyCenter observatory in Arizona's Santa Catalina Mountains in January, and determined that it takes about 1,350 years to circle the sun once. The comet has begun to follow a path underneath the Big Dipper in Ursa Major and will be closest to the Earth on October 21, according to EarthSky.org, which is around the same time that the Orionids meteor shower is set to reach its peak. Don't Miss The Orionid Meteor Shower Peaks This Month—Here's How to See the Most Shooting Stars Here's When Fall Foliage Will Reach Peak Color in Your State The comet will continue to brighten after that, likely reaching its brightest around October 31 or November 1, at which point it may be visible with the naked eye in dark, non light-polluted skies. The comet reaches its closest point to the sun on November 8. To catch the comet during the first half of the month, look up in the early morning hours before sunrise, per EarthSky.org. It will still be dim at this point, so you'll need a pair of binoculars or a telescope to see it. If predictions are correct, the comet will brighten in late October as it gets closer to Earth and may be visible with the naked eye in dark conditions. According to Live Science, photos of the comet show it giving off a green glow, which is likely caused by the presence of diatomic carbon within its coma. Diatomic carbon, also known as dicarbon, is a gaseous form of carbon found in space and comets. Explore more: News Space & Weather News