DENVER (KDVR/NEXSTAR) — Jupiter and Saturn are about to appear closer in the sky than they have in 400 years and you can watch the event thanks to the Lowell Observatory in Flagstaff, AZ.

The two planets will be so close that they will appear to be touching, separated by one-fifth the diameter of a full moon.

“They’re not close in space – they’re still hundreds of millions of kilometers apart from each other said, NASA Astronomer Henry Throop. “But … they appear as two points very close in the sky … in fact they’re so close that if you extend your pinky at arms length you’ll be able to cover both planets with just your pinky finger.”

Throop says Jupiter will look like the brightest star in the sky (it’s not a star, of course, it’s simply reflecting the sun). Saturn will be slightly fainter and found above and to the left of Jupiter.

There is nothing like the perspective of a once-in-a-lifetime event than that from a child. One young girl expresses her excitement with her family about the Great Conjunction.

“This time is the only time we’re ever going to get to see it in our whole lives; our grandchildrens’ lives,” she says.

Observers gathered on Green Mountain in Lakewood to get a clear view. Some donned telescopes, others with binoculars.

While some gathered to stare up at the sky, others chose to remain at home and submit photos to the site. Check out our viewer photo gallery.