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Period of Neptune's orbit (164.8 y) is 2 x Length of reign of King Sobhuza II of Swaziland (82 y)
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Distance to the Heliopause (limit of the Solar System) (17.95 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.