Comet Leonard (C/2021 A1) was one of the most anticipated comets of recent years, discovered on January 3, 2021, by astronomer Gregory J. Leonard at the Mount Lemmon Observatory in Arizona. What made this comet so exciting was its exceptionally long orbital period—roughly 80,000 years. This meant it had last passed through the inner solar system when early humans were just beginning to venture across the globe. Sadly, its December 2021 visit was also its last; after swinging around the Sun, Comet Leonard was ejected from the solar system, destined to drift through interstellar space forever.

Nicknamed the “Christmas Comet,” Leonard became a favorite among skywatchers during the holiday season of 2021. Though it never reached the naked-eye brightness of some famous comets, it still put on a memorable show for observers with binoculars or telescopes, displaying a greenish coma and a long, dynamic tail shaped by the solar wind. Its close approach to Earth on December 12, 2021—just 21 million miles away—made it the brightest comet of that year. The fleeting nature of Comet Leonard’s passage reminded astronomers and enthusiasts alike of how rare and precious such celestial events are, offering a once-in-a-lifetime glimpse before the comet faded into the darkness of deep space.

This image of Comet Leonard may not be perfect, but it represents the best I was able to capture during its brief visit. The final result is a stack of ten 60-second exposures taken early on the morning of December 2, 2021.