Did you know?
Diameter of Neptune (49,200 km) is 40 x Length of the Rhine River (1,233 km)
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Mass of an emergency spare tyre for a small car (11.7 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.