An hour after sunset on Dec. 21, millions are expected to see the much-awaited planetary kissing of Jupiter and Saturn, called the 'Great Conjunction' or 'Christmas star.'

But, did you know what will happen to Earth after this phenomenon?

How to see Jupiter and Saturn 'Great Conjunction'

What Happens to Earth in the Dec. 21 Jupiter and Saturn 'Great Conjunction'
(Photo : Photo by Richard Heathcote/Getty Images)
Jupiter and Saturn are seen in close proximity to each other on December 20, 2020 in High Wycombe, England. Jupiter and Saturn meet in closest ‘great conjunction’ since 1623 on Monday 21st December when they will almost appear right next to each other.

Tonight a lot of people have witnessed how the two giant planets Jupiter and Saturn, have nearly overlapped each other with the once-in-a-lifetime event of 'Great Conjunction.'

After 800 years, this phenomenon happened again amid the upcoming holidays, which why it was named as 'Christmas star.'

EarthSky reported that the two planets were just 0.1 degrees apart from each other on Dec. 21. The last time this happened was in 1623.

What happens to Earth

What Happens to Earth in the Dec. 21 Jupiter and Saturn 'Great Conjunction'
(Photo : Photo by Lynette Cook/NASA/Getty Images)
This artist's conceptual drawing released June 13, 2002 depicts a Jupiter-mass planet orbiting the star, 55 Cancri, about 41 light years from Earth. A possible moon around the planet is shown because such moons are thought to be common around this type of planet, but no moon has been detected.

Earth is distant from these two giant planets however, did you know that there's a particular benefit of these giant planets to humans?

In 2016, Space reported that Jupiter and Saturn pose an important benefit for planet Earth.

According to Tom Barclay, of NASA's Ames Research Center in Moffett Field, California, these giant planets protect Earth from giant impacts of asteroids, striking from the space.

"If you have giant planets, your last giant impact happens somewhere between 10 and 100 million years [after planet formation], which is pretty fine - it's like what happened on Earth," Barclay said. "If you don't have giant planets, the last giant impact can happen hundreds [of millions] to billions of years in. This really is a risk to habitability."

In the recent 'Great Conjunction,' this was one of the possible threats. However, experts do not conclude any harm for Earth in today's phenomenon. Now, that's a good thing.

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