The “Christmas star,” one of the most unique planetary events in centuries, will appear in the sky Monday evening, Dec. 21. There’s just one big problem: Mother Nature will be spoiling the view here in New Jersey, with heavy cloud cover and light snow showers in the weather forecast.
However, there is some good news. Experts say we will get another shot at seeing this special “star” — actually Saturn and Jupiter sitting very close together in the sky, making it appear to be one big twinkling star — on Tuesday night, Dec. 22. That’s when skies in New Jersey are finally forecast to be mostly clear.
Even though our solar system’s two largest planets won’t be as super, super close as they will be after sunset Monday, they will still be pretty darn close on Tuesday, according to astronomy experts.
“Today (Monday evening) they are going to be as close as possible,” said Amie Gallagher, director of the planetarium at Raritan Valley Community College in New Jersey. After sunset on Tuesday, “they’ll still be really close, but not as close as they are today…. They’ll still look very, very close together.”
In case you never took an astronomy class and you’re wondering why Saturn and Jupiter won’t be positioned in the same spots just 24 hours apart on Monday and Tuesday, the answer is simple.
“They’re always moving, like trains on a train track, in their own orbit,” Gallagher said.
Those planets are actually moving through the solar system — hundreds of millions of miles apart from each other — but from our vantage point here on Earth (which is also moving and spinning), they will appear to be very close together both Monday evening and Tuesday evening, she noted.
Ready for the "Christmas star?" Saturn, top, and Jupiter, below, are seen after sunset from Shenandoah National Park in Virginia on Sunday, Dec. 13, 2020. The two big planets are drawing closer to each other in the sky as they head towards a “great conjunction” on Dec. 21, where they will appear a tenth of a degree apart.NASA/Bill Ingalls
Best viewing time
With sunset scheduled at 4:32 p.m. Monday and one minute later on Tuesday, experts say sky watchers who want to catch a glimpse of the so-called Christmas star should try to find a location with a clear view of the southwestern sky.
Although it’s better to pick a spot away from city lights or street lights for the best view, space experts at NASA say Jupiter and Saturn are bright enough to be visible in most cities. The planets will be low in the southwestern corner of the sky.
Gallagher says the most ideal viewing time will likely be between 5:15 p.m. and 6:30 p.m. Monday or Tuesday, because the sun will be down for a while by then and Saturn and Jupiter will be setting by 7 p.m.
NASA says about an hour after sunset, in the southwestern sky, “Jupiter will look like a bright star and be easily visible. Saturn will be slightly fainter and will appear slightly above and to the left of Jupiter until December 21, when Jupiter will overtake it and they will reverse positions in the sky.”
The two big planets can be seen with the naked eye, “but if you have binoculars or a small telescope, you may be able to see Jupiter’s four large moons orbiting the giant planet,” NASA notes.
Just by chance, the close alignment of these two big planets happened to be timed to the Dec. 21 winter solstice, the official start of the winter season here in the northern hemisphere. It also happens to be the peak period of a late-December meteor shower known as the Ursids.
Cloudy skies will also block the view of this meteor shower in New Jersey late Monday night into early Tuesday morning, but some meteors still should be visible from dark locations Tuesday night into Wednesday morning.
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Len Melisurgo may be reached at LMelisurgo@njadvancemedia.com.