Jupiter, Saturn to come close to each other on December 21 after 397 years

In a rare celestial event, Jupiter and Saturn will be seen very close to each other on December 21, appearing like one bright star.

The two planets have never been so close since 1623, and hence, the term "a great conjunction", Director of M P Birla Planetarium, Debi Prasad Duari, said in a statement.

"If two celestial bodies visually appear close to each other from Earth, it is called a conjunction. And such conjunction of Saturn and Jupiter is at times called a great conjunction," he said.

The planets will next come comparably close on March 15, 2080.

On the night of December 21, their physical distance will be around 735 million km, Duari said.

In the run-up to the date, both planets will appear to progressively come closer to each other, with every passing day, he said.

In most major cities across India, the conjunction could be seen just after sunset.