Mimas, a moon of Saturn, has a crater so big that it looks like the Death Star from Star Wars.
Why it is true
Herschel crater is about 139 km wide, roughly a third of the moon's entire diameter. The impact that made it nearly shattered Mimas. The film came out in 1977; the crater was only photographed in 1980, by Voyager 1.
Source: NASA Science
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