It's time for my annual Starwatch column when I like to suggest what can be considered the "Christmas star" for the holiday season. Most years, it's not actually a star, but rather, a planet. The original Christmas star cited in the Bible could have very well been a supernatural event. Or it may have been an exploding star, otherwise known as a supernova.

The original Christmas star could have also been a bright conjunction of two or more planets. Astronomers can clearly trace back past conjunctions, as well as future ones. If it was a conjunction, it's difficult to tell which close encounter of planets in the sky could have been the Christmas star, since the exact year of Christ's birth is uncertain.

This year, we have a truly tremendous and historic conjunction in the early evening Rochester sky that I certainly would consider the Christmas star for 2020.

It's the extremely close pairing of Jupiter and Saturn, the closest they've been to each other in the night sky since 1623.

The two planets pop out in the early evening twilight in the very low southwest sky. Don't delay checking them out, because they set below the horizon shortly after 6:30 p.m. If you have a high tree line or house that blocks your southwest horizon, you will most likely have to move to a more open area or to the top of a hill to see the tight hug between Jupiter and Saturn.

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Throughout the autumn, the largest planets in our solar system have been drawing closer and closer to each other, and next Monday, Dec. 21, they'll be at their closest, only a tenth of a degree apart. Incidentally, Monday is also the winter solstice this year, the first day of winter. Jupiter and Saturn are so close together, they'll almost appear as a double planet.

Jupiter is the brightest of the two, with Saturn just above Jupiter. Their combined light should make a spectacular sight.

Unfortunately, the view of the planets through a small telescope or pair of binoculars won't be all that great. Because they're so close to the horizon, they'll appear really fuzzy. Nonetheless, you'll see the disk of Jupiter and some of its moons. You'll also see a fuzzy version of Saturn’s ring system. The cool thing is that both planets can fit in the same field of view.

Jupiter and Saturn aren't actually close to touching. They're nowhere near each other in reality. They just happen to be in almost the exact same line of sight. As Jupiter and Saturn circle around the sun in their separate orbits, they appear relatively close to each other in the sky about every 20 years from our vantage point on Earth.

This time around, though, they appear to be extra close because their orbital planes are intersecting from our point of view. How this happens is another story for another day. After next Monday, the planets will very gradually begin to part company in the heavens from night to night, but they'll still be close enough to make this holiday season, a strained one for sure, a little brighter.

Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul and is author of the book, “Stars, a Month by Month Tour of the Constellations” published by Adventure Publications. Send questions to mikewlynch@comcast.net.

The Rochester Astronomy Club welcomes new members and puts on public star parties. Their website is rochesterskies.org.