'Christmas Comet' Leonard Shines Brighter Ahead of Leaving Our Solar System

Already the brightest comet of 2021, Comet Leonard is undergoing outbursts of light, with the latest occurring on Monday. The comet increased in brightness by 10 times in its latest outburst, according to Spaceweather.com.

Comet Leonard, labeled by some as the "Christmas comet" as a result of its timing, is currently making its way towards the sun and, like most comets, is gradually brightening as it does so.

But, Comet Leonard, named after the astronomer who discovered it in January 2021 Greg Leonard, a senior researcher at the University of Arizona, is also undergoing periodic outbursts of brightness.

The first reports of the comet, officially designated C/2021 A1, undergoing such an outburst came in a week ago on December 13. When this was repeated on December 20, many astronomers and astrophotographers were able to capture the phenomenon.

Tel Lekastas, a mathematician and keen astrophotographer with a passion for capturing images of comets, posted images of the December 20 outburst to his Twitter feed.

The outbursts of brightness could be the result of heat from the sun liberating ice and dust from the comet's core as it makes its close approach to our star. This could be causing Comet Leonard's core to fragment, and could even be blowing away massive chunks of ice and rock, according to Spaceweather.com.

The comet, which made a close approach to Earth's closest planetary neighbor Venus on December 17 and 18, is best viewed with a telescope and binoculars. Located to the left of the brightest planet in the night sky, Comet Leonard is just barely visible to the naked eye. Currently, Spaceweather.com says that it is best viewed from Earth's Southern Hemisphere.

Spotting Comet Leonard, a visitor from the outer edges of the solar system, is likely to be a once-in-a-lifetime chance that is rapidly running out for astronomers and stargazers. The comet will make its closest approach to the sun on January 3, at which point it will be 57.2 million miles from our star. After that, the comet will pass out of view from our vantage point on Earth.

The chances of a return visit are diminishingly small. Even if the intense heat and radiation from the sun doesn't cause Comet Leonard to fragment further, its discoverer warns that it may be headed out of our cosmic neighborhood for good.

"This is the last time we are going to see the comet," Leonard said. "It's speeding along at escape velocity, 44 miles per second. After its slingshot around the sun, it will be ejected from our solar system, and it may stumble into another star system millions of years from now."

The comet's namesake also had some advice on how to spot it before it is too late. Leonard said in a press release from the University of Arizona: "Find yourself a dark sky with a good view of the horizon, bring binoculars and I think you may be rewarded."

A stock image shows an astronomer looking at the sky. (Right) An image of Comet Leonard taken on December 4, 2021. Getty Images