Everybody loves Mimas. No, not the Greek Titan whose legs were snakes, but Mimas the moon of Saturn — which was named after that mythical character. Mimas is especially popular with sci-fi fans because its massive Herschel Crater — named for English astronomer William Herschel, who discovered this moon in 1789 — makes Mimas look kind of like the Death Star from Star Wars.
In 1980, NASA’s Voyagers I and II spacecraft sent back some fuzzy shots of Mimas. But we got a really good look in 2010, when NASA’s Cassini explorer started sending back high-quality images of this, the smallest and closest of Saturn’s seven moons.
And now for some fun facts about Mimas.
How small is it?
Its face is smaller than 250 miles across.
How close is it?
Its orbit is elliptical, but Mimas’s averages a distance from Saturn of about 125,000 miles. (Earth’s moon averages about 239,000 miles from us.)
How long does Mimas’s orbit take?
The orbit around Saturn takes about 23 hours — exactly half the time it takes Tethys, a sister moon.
How about all those craters?
They cover Mimas’s surface, making it one of the most crater-pocked things in our solar system.
How big is the biggest crater?
The Herschel Crater sprawls across one-third of the moon’s face, about 81 miles, and its outer walls are more than three miles high! The impact could have destroyed Mimas, according to some scientists. But it didn’t. #MimasStrong
So what’s Mimas made of?
Thanks to its low density, we think it’s mostly ice.
Any other pop-culture references we should know about?
Why yes! In 2010, Cassini’s heat-detecting equipment (a composite infrared spectrometer) identified a V-shaped range of hot surface on the moon’s left side. Because heat shows up as red and yellow, it looks a lot like a Pac-Man that’s just about to chow down on the Herschel Crater.
And that’s just one more reason that everybody loves Mimas. Star Wars, Pac-Man, and a whopping big crater … what more could you ask of one little moon?