CINCINNATI – It was an astronomical event that humans have not been able to observe in the night sky since the 13th century, and Cincinnati Observatory astronomer Dean Regas wouldn’t miss it.
On Monday evening, Regas pointed the observatory’s 175-year-old telescope at a small field in space and recorded video of the “Great Conjunction” of Jupiter and Saturn. It was the closest approach between the two largest planets in the solar system since 1623, but it had been about four centuries since the spectacle was last seen at night.
While the two planets were closest on Monday night, it’s not too late to see the rare celestial show: Weather permitting, the planets would still be seen in close conjunction Tuesday night, Regas said.
“Look southwest between 6:00 PM and 6:45 PM, where you’ll see two bright dots,” Regas said. “To the naked eye, Jupiter will be brighter with Saturn dimmer to the side. You should be able to see both planets through a backyard telescope at the same time.”
Although the two planets meet at a relatively close distance once every few decades, the distance so close and visible from Earth is extraordinarily rare, NASA officials said.
“You can imagine the solar system being a racetrack, with each of the planets like a runner in their own orbit and the Earth toward the center of the stadium,” said Henry Throop, an astronomer with the Planetary Science Division at NASA. headquarters in Washington. “From our vantage point, we can see Jupiter on its inner orbit, approach Saturn for the entire month, and finally overtake it on December 21.”
It just happened that Jupiter and Saturn were closest to each other on the evening of the winter solstice, the longest night of the year.
The proximity of the Christmas holidays was also coincidental, but led some to call the event the “ poinsettia ” even if it only involves planets.
Reporter Justin Boggs of the Scripps National Desk contributed to this story.