MADISON, Wis. –– A lot has been unique ​about this year: mostly unique in a bad way. But if you look at the sky Monday evening, you’ll see something special, hundreds of years in the making.

“The Great Conjunction” will put on a show for the world Monday evening. Jupiter and Saturn will be so close, they’ll almost look like just one star.

“It’s a one-in-a-lifetime opportunity for many of us,” said Dixie Burns. Burns teaches astronomy and other sciences at Madison Area Technical College.

The two planets have been moving closer together all year in their orbits around the sun. “It takes Jupiter almost 12 years to go around the sun, and Saturn almost 30 years to go around the sun. So every 20 years, they're in the same section of the sky,” Burns said.

But this is different from what normally happens every 20 years. “What’s special about this one is not only are they in the same section sky, they're really close to each other in the sky,” Burns said.

They’ll be just one tenth of a degree apart; about the size of two of Earth’s moons. They might look like one super bright star.

The last time the two planets were this close together was in the 1600s. It was cloudy and not visible. The conjunction was last visible in March of 1226, nearly 800 years ago.

It’ll be visible in the hour after sunset on Monday. “All you need to do is go outside after sunset, look low in the West,” Burns said. “Jupiter will be the brightest star-like object, brighter than all the brightest stars. Saturn’s about the same brightness as the brightest stars.”

In this difficult year, a rare natural phenomenon could feel a little more special.

“Any excuse to get outside and look up at the nighttime sky, I’m all for,” Burns said.

"There’s nothing like just looking up and letting go.”

You should be able to see the conjunction with the naked eye. Burns enjoys using binoculars even more than a telescope.