Did you know? Diameter of Neptune (49,200 km) is 25 x Length of the Tigris River (1,950 km)
Distance from the Sun to Neptune (4.5 billion km)
/fact/distance-from-the-sun-to-neptune
Link
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.