Two planets cross paths in the evening sky this week. One is brilliant, the other a little too faint to see without some help.

The brilliant one is Venus, the “evening star.” In all the night sky, only the Moon outshines it, so you can’t miss it. But you can miss Uranus. It’s a giant, but it’s so far away that it’s not easy to see.

Several factors control how bright a planet looks: the planet’s distance from both Earth and the Sun, its size, and how much sunlight is reflected from its surface.

The clouds that blanket Venus reflect much more sunlight than the clouds of Uranus do. And while Uranus is about four times the diameter of Venus, right now it’s almost 14 times farther. That makes it look smaller in our sky.

The distances are also important in another way. The farther an object is from the Sun, the feebler the Sun appears. At their average distances from the Sun, each square foot of Venus receives more than 700 times more sunlight than the same size patch of Uranus. At the same time, the farther an object is from Earth, the less of its light we receive.

When you put it all together, Venus looks more than seven thousand times brighter than its giant sibling.

Venus blazes into view as twilight fades. Uranus is a couple of degrees to its upper left, and it’s an easy target for binoculars. The two worlds will stand almost side by side on Thursday, just a fraction of a degree apart.

Script by Damond Benningfield