Jupiter and Saturn Will Be the Closest They’ve Been in 800 Years

In just a few days, you’ll be able to catch a light show that humanity hasn’t seen in nearly 800 years. On Dec. 21, Jupiter and Saturn will align in a position known as the great conjunction, which is the point at which they're closest to each other in the night sky as seen from Earth. This phenomenon is often also referred to as the "Christmas star."  The last time humans were able to see a great conjunction this close was in 1226.  You definitely won’t want to miss it this time around because after Dec. 21, Jupiter and Saturn won’t be this close until March 15, 2080.