Did you know?
Pop. of Johannesburg, South Africa (4.43 million people) is 5 x Pop. of Djibouti (884,000)
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Mass of Hyperion (moon of Saturn) (5.6 quintillion kg)
If this was a standard unit ...
Yes, there's now a book based on these numbers. Oxford University Press: July 2018.
Click here to learn more about it.
Click here for Podcast: Andrew Elliott interviewed for New Books Network.