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Estimated world population of Grey Seal (400,000 individuals) is 4 x Estimated world population of Japanese Serow (100,000 individuals)
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Distance to the Oort Cloud (748 billion km)
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.