Comet visit Earth before disappearing 80,000 years

Comet Leonard with an 80,000-year orbit is passing close to Earth, becoming the brightest comet of the year and offering a rare viewing opportunity.

Astrophotographers around the world are taking advantage of the precious opportunity to capture comet Leonard as it passes close to Earth, Newsweek reported on December 9. Leonard, or C/2021 A1, is the brightest comet of the year. It was discovered in January by Gregory J. Leonard, an astronomer at the University of Arizona.

Picture 1 of Comet visit Earth before disappearing 80,000 years
Photographer Will Leverett photographed comet Leonard from Llano County, Texas, USA, on December 8.

In the months that followed, the researchers noted that Leonard's orbit would bring it fairly close to Earth on its way toward the Sun, and that people would probably see it with the naked eye in December. But when Leonard actually came close to Earth, it was not easy to see with the naked eye, although some sharp-eyed people can see this comet in very dark and clear conditions. The use of telescopes and binoculars will make observations much better.

In North America and similar latitudes, astronomers can see Leonard by looking east about 45 minutes before sunrise, below the North Star and Arcturus. This will be true until 12/12. Then, the best time to observe comets is in the evening, after sunset. People can see the comet in the southwest as it moves past Venus and Mercury, toward Saturn and Jupiter.

Leonard has an orbital period of about 80,000 years, which means it takes that long to orbit the Sun. The reason is that its orbit is very eccentric, more like an oval than a circle. This means that astronomy lovers on Earth won't see it again for a long time.

However, it's possible that Leonard won't last that long either. This comet appears brighter than usual because it is relatively close to Earth, but in fact it is dimming. According to Quanzhi Ye, an astronomer at the University of Maryland, there are many speculations about why Leonard is dimming, but the most obvious reason is that it is or is about to decay.

Comets are spheres of ice, gas, and rock that move around the Sun. As they approach the Sun, they heat up and spew matter back, leaving behind a characteristic tail that can be millions of kilometers long. Finally, comets are likely to evaporate almost completely. Scientists are not sure if this is what is happening with Leonard.

According to NASA, the number of comets detected so far is 3,743, but the total number of comets orbiting the Sun could be in the billions.