If Estimated volume of water on Callisto (moon of Jupiter) (5.3 sextillion L) was a standard unit ...
Estimated volume of water on Europa (moon of Jupiter) (2.6 sextillion L)...more would be 1/2 of Estimated volume of water on Callisto (moon of Jupiter)
Read all about it!
Is That a Big Number? - the book - is now available from all good booksellers.
"This is a fun and riveting book. Written in an accessible and engaging way, it is unputdownable." Frost Magazine