Be sure to look up tonight!
If there’s anything positive to take from this tumultuous year, it’s the number of astronomical spectacles we’ve been treated to — from supermoons to meteor showers! And with all the magical lights that the holidays bring, it’s easy to forget that the sky provides some stunning celestial light shows of its own.
After much anticipation, the rare celestial event the “Great Conjunction” is taking place tonight, December 21! This is when the two gas giants, Jupiter and Saturn, will align extremely close to one another and shine brightly as a “double planet.”
The orbits of Earth, Jupiter, and Saturn cause this phenomenon to happen once every 20 years. According to NASA, Jupiter takes 12 years to orbit the sun while Saturn’s orbit takes 30 years and so every couple of decades, Saturn is lapped by Jupiter. But to find the last time the planets were this close together in the night sky, you’ll have to look all the way back to medieval times nearly 800 years ago, on March 4, 1226.
For Christians observing the holiday, the event, sometimes called the ‘Christmas Star’, holds even more meaning. Jupiter and Saturn’s alignment is theorized to be the ‘Star of Bethlehem’ that the three wise men followed on Christmas Eve in the biblical text.
In NYC, Museum of Natural History astronomer Jackie Faherty told Scientific American that you’ll be able to see it from the naked eye, no telescope or binoculars needed (though of course they’ll give you an even better view).
Look to the the horizon in the hour after sunset (4:31 p.m. today) and watch Jupiter appear in the western sky first, followed by Saturn. They will be quite large and bright, but will be different from other stars because they won’t be sparkling.
The next time the planets will be this close together again (by six “arc minutes”) will be 2080 — so make it count!
[Featured image from Unsplash]