On Monday, December 21, 2020, you can witness something not seen in nearly 800 years.
During the winter solstice, Jupiter and Saturn will line up to create what is known as the “Christmas Star” or “Star of Bethlehem.”
These two planets haven’t appeared this close together from Earth’s vantage point since the Middle Ages. In reality, of course, they won’t be close at all. They only appear to be aligned to us on Earth.
“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, astronomer at Rice University, told Forbes. “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.”
Stargazers in the northern hemisphere should turn their heads and telescopes to the southwest portion of the sky about 45 minutes after sunset to see the planets align Dec. 21. However, reportedly sightings can be seen throughout that entire week.
According to NASA astrophysicist Dr. Amber Straughn, a star-sighting of this magnitude won’t occur again until the 2080s.
You’ve probably already seen three bright points of light in the sky and wondered what they are. Jupiter and Saturn have appeared to be relatively close to each other for most of 2020 near the constellation of Sagittarius, but they now appear to be getting closer to each other as the year goes by.
A spectacularly close “great conjunction” of the two planets takes place on December 21, 2020, the date of the winter solstice. The alignment of the two planets is going to be the view of the year, celestially-speaking.
You can expect to see the phenomenon 45 minutes after the sun sets. The Christmas Star should be visible with your naked eye when looking to the southwest. Of course, if it’s a cloudy night you may be out of luck.
For those observing the Christmas holiday, the phenomenon may hold even more meaning. It’s widely theorized that the star the three wise men followed may have really been a similar planetary alignment of Jupiter and Saturn.