From our perspective here on Planet Earth, on December 21st, 2020, Jupiter and Saturn will be pass each other by only 0.1 degrees or 1/5th the diameter of a full moon. This is an extremely rare event so take a moment on a clear night just after Sunset to see this amazing event! A great conjunction, or meeting of the two big planets Jupiter and Saturn in the night sky, occurs every 20 years but this is the closest conjunction since 1623, only 14 years after Galileo pointed the first telescope to the night sky. In 1623, it was also only 13 degrees from the Sun so it is unlikely that many got the chance to observe it. According to Earthsky.org, the closest observable Jupter-Saturn conjunction that was as close was all the way back in 1226! If you miss this event, they will meet in the sky again in 20 years but the two planets won’t appear so close together again until March 15, 2080!
Look for this conjunction in the SouthWestern sky shortly after Sunset, which is around 4:45 PM in December. The graphic below from Earthsky.org, provides a rough view of where to find the Moon, Saturn and Jupiter 45 minutes after Sunset.
