How to See Comet Lemmon This October

It was early January 2025 when a faint light spot was observed at the Mt. Lemmon Observatory in Arizona. Follow-up observations revealed that the object was a comet visiting from the outer edge of the solar system, and it was named Comet Lemmon (C/2025 A6). Its “period”—the time it takes to complete its lengthy orbit of the sun—is about 1,350 years.

At first, the comet was so faint that it could only be seen with specialized equipment. But it has brightened rapidly as the months have passed, and by the time fall arrived, it was bright enough to be viewed with binoculars. It will now get brighter still, as it gets closer to both the Earth and the sun, and may even become visible with the naked eye.

According to NASA, Comet Lemmon will be closest to Earth around October 21, 2025, passing at a distance ...