CINCINNATI – It was an astronomical event that people could not observe in the night sky in the thirteenth century, and astronomer Dean Regas of the Cincinnati Observatory would not miss.
On Monday night, Regas aimed the observer’s 175-year-old telescope at a small field in space and recorded the video “The Great Conjunction” of Jupiter and Saturn. It was the closest approach between the two largest planets in the solar system in 1623, but about four centuries earlier, the spectacle was last visible at night.
As the two planets approached on Monday night, it is not too late to catch the rare celestial spectacle: weather permitting, the planets will still be visible in close connection again on Tuesday night, Regas said.
“Head southwest between 6:00 and 6:45 p.m., where you’ll see two bright spots,” Regas said. “With the naked eye, Jupiter will be the brightest, with a weaker Saturn on the side. Through a telescope in the backyard, you should be able to see both planets at the same time.”
While the two planets converge at a relatively close distance every few decades, the distance being so close and visible from Earth is extremely rare, according to NASA officials.
“You can imagine that the solar system is a racetrack, with each of the planets as a runner on its own lane and the Earth toward the center of the stadium,” said Henry Throop, an astronomer in the Division of Planetary Sciences at NASA’s Washington headquarters. “From our point of view, we will be able to see Jupiter in the inner band, approaching Saturn all month and finally surpassing it on December 21.”
It was by chance that Jupiter and Saturn lined up closest on the evening of the winter solstice, the longest night of the year.
Its approach to the Christmas holiday was also accidental, but led some to call the event the “Christmas star,” even though the event involved only planets.
Scripps National Desk reporter Justin Boggs contributed to the story.