More Moon and Saturn

StarDate: November 12, 2009

You are missing some Flash content that should appear here! Perhaps your browser cannot display it, or maybe it did not initialize correctly.

audio/mpeg icon

If you check out the album of pictures from the Cassini spacecraft, you might think you've stumbled into another episode of "Star Wars." But what looks like a "death star" is really one of the moons of Saturn -- one that survived a near-death experience.

Mimas is a ball of ice and rock that's about as wide as Iowa.

Like many of the moons of the solar system, the surface of Mimas is covered with craters -- the scars of collisions with smaller objects. Most of the craters aren't all that interesting. But one has earned Mimas a nickname: the Death Star Moon. That's because the crater makes the little moon look like the famous Star Wars battle stations.

The crater is about 80 miles across -- one-third the diameter of Mimas itself. It's six miles deep, and has a central mountain peak that's about four miles high.

The crater formed when an asteroid or comet slammed into Mimas. The impact was so powerful that it probably cracked the moon all the way through. Had it been just a little more powerful, Mimas would've been pulverized -- perhaps forming a new ring around Saturn.

Instead, Mimas appears to sweep out a wide gap in the rings, as some of the tiny particles that make up the rings march in step with the Death Star Moon.

Saturn is in fine view early tomorrow. It's in the east at first light, standing almost directly above our own Moon. Saturn looks like a bright golden star, shining steadily in the growing light of dawn.

Script by Damond Benningfield, Copyright 2006, 2009

For more skywatching tips, astronomy news, and much more, read StarDate magazine.

The one constant in the Universe: StarDate magazine


©2014 The University of Texas McDonald Observatory