Did you know?
Diameter of Mars (6,790 km) is 5 x Road distance from Land's End to John o' Groats (1,350 km)
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Distance a kangaroo can jump (13.5 m)
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.