Will weather conditions be right to see rare ‘Christmas Star’ here tonight?

Don’t forget to look up at the sky Monday about an hour after sunset for a rare treat — a “Christmas Star” that hasn’t been seen in hundreds of years. And let’s hope the weather plays along.

The “Christmas Star” phenomenon is actually the planetary conjunction of Jupiter and Saturn coming together in the sky in an especially vibrant way, according to NASA. It has been seen for the last few nights but it will be brightest on Monday night.

Planets appear to pass each other in the night sky fairly often and the positions of Jupiter and Saturn align once every 20 years. However, according to NASA, this is the first time in nearly 400 years that the planets passed by this close to each other and the first time in nearly 800 years since Saturn and Jupiter have aligned at night.

On Monday night, Jupiter and Saturn will appear so close that a pinkie finger at arm’s length will easily cover both planets in the sky, NASA astronomers say. You won’t even need a telescope to see the planets if you look toward the southwest just after sunset.

“You can imagine the solar system to be a racetrack, with each of the planets as a runner in their own lane and the Earth toward the center of the stadium,” said Henry Throop, astronomer in the Planetary Science Division at NASA Headquarters in Washington. “From our vantage point, we’ll be able to be to see Jupiter on the inside lane, approaching Saturn all month and finally overtaking it on December 21.”

While the conjunction is happening on the same day as the winter solstice, astronomers say the timing is merely a coincidence, based on the orbits of the planets and the tilt of the Earth.

“Conjunctions like this could happen on any day of the year, depending on where the planets are in their orbits,” said Throop. “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.”

Here’s how you can see the Christmas star:

• Find a spot with an unobstructed view of the sky, like a field or park. Jupiter and Saturn are bright, so they can be seen even from most cities.
• An hour after sunset, look to the southwestern sky. Jupiter will look like a bright star and be easily visible, which on Monday night will appear above a slightly fainter Saturn.
• The planets can be seen with the unaided 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.

The forecast

You might have a small window to see the rare “Great Conjunction” Monday night. Sunset in Santa Cruz will be at 4:55 p.m. and at 5 p.m., the sky will be mostly clear with intermittent clouds showing up by 6 p.m.

Did you get a picture of this rare “Christmas Star?” Share it with us below: