NASA officials say this “great conjunction” won’t be seen again until 2080
As Christmas nears, astronomers are urging citizens to look to the sky in a few weeks to witness something not seen in almost 800 years.
From Earth’s viewpoint, Jupiter and Saturn are getting very close to one another and will look like a double planet when they appear to nearly collide on Dec. 21 — the date of the winter solstice — forming a rare phenomenon known as a “Christmas star.”
“Alignments between these two planets are rather rare, occurring once every 20 years or so, but this conjunction is exceptionally rare because of how close the planets will appear to be to one another,” Patrick Hartigan, an astronomer at Rice University, told Forbes.
Forbes reported that Jupiter and Saturn will look like a “double planet” for the first time since the Middle Ages.
“You’d have to go all the way back to just before dawn on March 4, 1226, to see a closer alignment between these objects visible in the night sky,” Hartigan told Forbes.
You’ll be able to witness the event in the sky through binoculars or a small telescope, according to NASA.
Both Jupiter and Saturn have been traveling across the sky together all year and during the first three weeks of December, the planets will continue to move closer after each sunset, NASA officials said.
On Dec. 21, the planets will appear just a tenth of a degree apart, which is equivalent to the thickness of a dime held at arm’s length, according to NASA.
This happens every 20 years this century; however, NASA officials said this event is “the greatest great conjunction between Jupiter and Saturn” and won’t happen again until the year 2080.
In astronomical terms, conjunction is when two objects line up in the sky.
Some astronomers believe that the “star of Bethlehem” was a conjunction between Jupiter, Saturn and Mars.