Rare 'Christmas Star': When To Look Up In Hudson Valley

HUDSON VALLEY, NY — All eyes will be on the sky Monday as Jupiter and Saturn come together to form the "Christmas Star," an occurrence so rare it hasn't happened for centuries.

The event is the same day as the winter solstice, the longest night of the year. Sunset around the Hudson Valley is at about 4:30 p.m. and, unfortunately, cloudy skies are expected. The planets will be most visible just after sunset to the southwest.

The last time Jupiter and Saturn were this close together was in 1623, according to NASA.

NASA gave tips on how to see the Christmas Star:

• Find a spot with an unobstructed view of the sky, such as a field or park. Jupiter and Saturn are bright, so they can be seen even from cities.
• An hour after sunset, look to 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 Dec. 21, when Jupiter will overtake it and they will reverse positions in the sky.
• The planets can be seen with a person's eyes, but with binoculars or a small telescope, a person may be able to see Jupiter’s four large moons orbiting.

In 1623, when Jupiter and Saturn traveled across the sky, Jupiter caught up to and passed Saturn in the astronomical event known as the "Great Conjunction," according to NASA. Although the conjunction between Jupiter and Saturn happens about every 20 years, this year, it holds great importance because Jupiter and Saturn will be just one-tenth of a degree apart from a viewer's perspective or about one-fifth the width of a full moon, according to NPR.

"I think it's fair to say that such an event typically may occur just once in any one person's lifetime," Vanderbilt University's David Weintraub, an astronomy professor, told NPR.

Written by Lisa Finn/Patch, with additional reporting by Michael Woyton/Patch.