Most of the time, you can’t tell much about how far away the lights in the night sky are just by looking at them. But you can tonight — at least for a bright trio: the Moon and the planets Jupiter and Saturn.

Not surprisingly, the Moon is the brightest member of the trio. And it’s also the closest — a quarter of a million miles away. Except for the occasional asteroid, no astronomical object ever gets closer to us.

Jupiter is to the right of the Moon, and it looks like a brilliant star. Right now, only Venus and Mars outshine it.

Jupiter is the largest planet in the solar system — 11 times the diameter of Earth. And it’s topped by bright clouds. The combination means it reflects a lot of sunlight our way. But its luster is dulled by its distance: roughly 485 million miles.

Saturn is above the Moon. The planet looks like a bright star, though not nearly as bright as Jupiter. It, too, is a giant world enveloped in clouds. And as a bonus, its rings reflect a lot of light as well. From a distance of 930 million miles, though, it can’t hold a candle to Jupiter.

There’s another way to look at the distances to these three bodies: how long it takes their light to reach Earth. For the Moon, it’s about one and a third seconds. For Jupiter, it’s about 43 minutes. And for distant Saturn, it’s almost twice that — eighty-three minutes for its light to travel from the giant planet to your eye.

Script by Damond Benningfield

Support McDonald Observatory