Here’s the story behind ‘The Great Conjunction,’ a rare celestial sensation
KANSAS CITY, Mo. — A rare, celestial event will be taking place in the evening sky on December 21st (which happens to coincide with the Winter Solstice) that you won’t want to miss: The Great Conjunction. This has also been referred to as the Christmas Star or the Star of Bethlehem. You may have noticed that over the Summer Jupiter and Saturn have been getting closer and closer together in the nighttime sky. Jupiter appears brightest with Saturn fainter and slightly above and to the left of Jupiter. On Monday, Jupiter will overtake Saturn and swap places. The two planets will look like a very bright star in the evening sky. They will be separated by only 1/5th the diameter of the full moon. The conjunction of these planets happens about every 20 years. But this conjunction is exceptionally rare because of how close the planets will appear to one another. In fact, you must go all the way back to March 4, 1226 to see a closer alignment visible in the night sky! The best time to view this for the U.S. will be in the early evening, between 5pm and 6pm, in the Southwestern sky. Once the skies go dark, the planets will be too close to the horizon for viewing.
The ‘Christmas Star’ will form this week. Here’s how to watch
December 21 is the shortest day of 2020, and that’s good news if you’re planning to scan the night sky for a celestial event that hasn’t been seen to this degree since Genghis Khan was alive. Jupiter and Saturn, the solar system’s largest planets, can now be seen creeping closer together in the night sky every evening this week. On the winter equinox, those planets will line up almost perfectly to look like a bright double planet in the night sky. The two planets will be so close that they will appear to be touching, separated by one-fifth the diameter of a full moon. When celestial bodies align, astronomers call it a conjunction, but since this one involves our solar system’s two biggest gas giants, it’s technically a “great conjunction.” Because the event is landing on a holiday week, many have begun calling the formation the “Christmas Star.” The planets are likely already visible on the southwest horizon after sunset, and dedicated viewers can see them form into alignment over the next week. Though the two planets will look close together by next Monday, they actually will be more than four times the distance between Earth and the sun. “Look for them low in the southwest in the hour after sunset,” NASA officials said in a press release. And on December 21st, the two giant planets will appear just a tenth of a degree apart – that’s about the thickness of a dime held at arm’s length! This means the two planets and their moons will be visible in the same field of view through binoculars or a small telescope. In fact, Saturn will appear as close to Jupiter as some of Jupiter’s moons.”