ASTRONOMY PICTURE

OF THE DAY

DECEMBER 15, 2020

Great Conjunction: Saturn and Jupiter Converge

EXPLANATION

It’s happening. Saturn and Jupiter are moving closer and will soon appear in almost exactly the same direction. Coincidentally, on the night of the December solstice -- the longest night of the year in the north and the longest day in the south—the long-awaited Great Conjunction will occur. Then, about six days from now, Saturn and Jupiter will be right next to each other—as they are every 20 years. But this juxtaposition is not just any Great Conjunction—it will be the closest since 1623 because the two planetary giants will pass only 1/10th of a degree from each other—well less than the apparent diameter of a full moon. In the next few days a crescent moon will also pass a few degrees away from the converging planets and give a preliminary opportunity for iconic photos. The featured illustration shows the approach of Saturn and Jupiter during November and December over the French Alps.

Illustration Credit & Copyright

Sebastian Voltmer