Many people know that around December 21 of each year, the Winter Solstice arrives. However, it wouldn’t be 2020 without something out of the ordinary happening! This year during the solstice we are in for a treat, with what many are calling “The Christmas Star.” The conjunction of Saturn and Jupiter will be responsible for this “star.” It is, however, not actually a star.
These two Jovian Gas Giants will appear to merge into one “star” on the evening of December 21, they however still remain millions of miles apart. The fact that this is occurring on the winter solstice is just merely a coincidence. Conjunctions of planets like this can happen on any day of the year. Henry Throop, an astronomer with NASA said, “The date of the conjunction is determined by the positions of Jupiter, Saturn, and the Earth in their paths around the Sun, while the date of the solstice is determined by the tilt of Earth’s axis. The solstice is the longest night of the year, so this rare coincidence will give people a great chance to go outside and see the solar system.”
If you want to view the conjunction, all you have to do is find an unobstructed view of the southwest sky. When you look up, you’ll see what looks like a large “star” in the sky. Even if you live in a major city, these planets are bright enough to be seen on a typical night, but when they appear to “merge” it will be even brighter and very easy to see.
What makes this one special is that the last time the planets appeared to be this close in the sky was in 1623 and it was dubbed “the Great Conjunction” by Galileo Galilei who observed it. The last time that a conjunction between Jupiter and Saturn occurred at night was nearly 800 years ago in 1226! The next one will occur in 2080. So be sure to get outside on the evening of December 21, if weather permits, and check out the “This Christmas Star”!
Sources
http://lasp.colorado.edu/outerplanets/giantplanets_whatandwhere.php
https://www.nasa.gov/feature/the-great-conjunction-of-jupiter-and-saturn