The Great Conjunction of 2020 is almost here and it’s reported to be one of the most historical astronomical events in centuries! FYI, a conjunction in astronomy terms is described by EarthSky as the “meeting of planets and other objects on our sky’s dome.”
This month, Jupiter and Saturn are scheduled to appear closest together on December 21, which is also coincidentally the winter solstice, a.k.a. the longest night of the year in the northern hemisphere. It’s a rare observable light show that stargazers can’t miss!
“Jupiter and Saturn will be so close that you will be able to fit them both in the same telescopic field of view,” notes NASA. The last time two planets were this close together and were observable to the naked eye was way back in 1226 A.D.
As the two gas giants draw close together, they may appear to any observer on the ground as a single bright star. Astronomers alternatively call this event as the “Christmas Star” as it was believed that it was the same "star" that shone over Bethlehem in the Biblical tale. If this were true, the two planets that could have caused the moment almost 2000 years ago were Jupiter and Venus.
Astronomy websites stress that a once-in-a-lifetime event to this degree won’t happen again until March 15, 2080 so make sure you’ve got your calendars marked for this one!
“Keep in mind that while the two gas giants may appear close, in reality they are hundreds of millions of miles apart,” reminds NASA. “This will still be quite a striking sight, but you will need to look fast as both planets will set shortly after sunset. Look above the western horizon after sunset for these bright, close planets—a clear view will help! “