- Photographers around the world captured Jupiter and Saturn aligning almost perfectly in the night sky this week.
- Monday was the closest the two planets have appeared in 800 years; the last time they were this close and visible was in 1226.
- The two planets align or conjugate every 20 years. But this year they were close enough to look like a “double planet.”
On the eve of the winter solstice, Jupiter and Saturn seemed to touch in the night sky.
The last time the two planets were so close from Earth’s point of view was almost 800 years ago. The astronomical event is called a conjunction, the term for an alignment of celestial bodies. Since this conjunction involved the two largest gas giants in our solar system, it is known as the great conjunction.
The conjunction was not a one-night event: the approaching of the planets in the sky began on December 17 and they will continue to appear together until Christmas Day. Monday was just when Jupiter and Saturn were closest. So if you haven’t seen it yet, you have a few more nights to try. This “Christmas star,” as the conjunction has been nicknamed, seemed brighter than almost all the stars in the sky, according to NASA. That made the two planets easy to photograph.
Katherine Trouche, a science communicator at NASA’s Jet Propulsion Laboratory, took an impressive photo (below) using her telescope and an iPhone XR.
“Being able to see five moons and two planets more than 400 million miles away using nothing but pieces of glass and metal is nothing short of amazing,” he told Business Insider.
Ad
A double planet
The distance between Jupiter and Saturn is actually more than four times greater than that between Earth and the sun.
But on Monday, the planets were separated in the sky by a distance equivalent to about a fifth of the diameter of a full moon. That’s so close that the two points of light formed a kind of double planet. People around the world captured the rare lineup over the past week.
—Nick (@EdgingtonNick) December 21, 2020
Photographer Alireza Vafa took this view of the moon, Jupiter, and Saturn over the Alborz Mountains in Iran.
A post shared by Alireza Vafa (@ ali.reza.vafa)
With Kolivas, an engineer and amateur astronomer from Australia, he took this photo on Sunday.
-Dr. With Kolivas (@ckpooldev) December 20, 2020
Gary Hershorn, a photographer based in New York City, encountered cloudy conditions Monday. But it did capture a shot of the two planets approaching each other the week before, over the Statue of Liberty.
“As a photographer, I was looking forward to seeing the ‘Christmas Star,'” he told Business Insider. “The two planets have been positioning themselves next to the Statue of Liberty for the past week getting a little closer each day. It was a beautiful sight to see last week when they came down behind the statue.”
The best time to glimpse the conjunction is at sunset, during the hour after sunset. Look low in the sky, to the southwest. (Websites like Stellarium can help you orient your telescope.)
For those who want to watch the event online on Tuesday, the New York Association of Amateur Astronomers is hosting a live streaming event from their telescopes on YouTube and Facebook Live beginning at 4:30 pm ET.
A rare celestial event
Jupiter and Saturn align to some extent every 20 years.
“But it’s fair to say that this conjunction is truly exceptional in that the planets get very close together,” explained Patrick Hartigan, a professor of physics and astronomy at Rice University, on his website.
In the last 2,000 years, there were only two times when Jupiter and Saturn got closer in the sky than this year. One was in 1623, but the glare of the sun made it impossible to see. The other was in 1226.
Viewers will have to wait until March 15, 2080 to see Jupiter and Saturn as close as they were on Monday.
“The biggest challenge is that you will have to stay alive for another 60 years to see it!” Hartigan said.
.
