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Distance to the Heliopause (limit of the Solar System) (17.95 billion km) is 4 x Distance from the Sun to Neptune (4.5 billion km)
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Pop. of Kolkata, India (4.49 million people)
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.