Astronomy Picture of the Day

Explanation: Comet Lemmon is putting on a show for cameras around the globe. Passing nearest to the Earth this week, the photogenic comet C/2025 A6 (Lemmon) is now extending two long tails: a blue ion tail and a white dust tail. The ion tail is pushed away from the Sun by the ever-present but ever-changing solar wind, and also shows structure determined by how much gas is ejected at any one moment. It glows because it is ionized by high-energy sunlight. The dust tail is pushed away from the comet by sunlight and shines by reflecting sunlight. The featured image is an enhanced composite of 50 exposures all taken two days ago from Mlynica, Slovakia. The mountains in the foreground are the High Tatras that partly separate Slovakia from Poland. Although Comet Lemmon is best visible in long camera exposures, the shedding ice ball has become faintly visible in northern skies even to unaided eyes through dark skies toward the west after sunset.