At Google we like to create solutions for the future. And we imagine a future where web use won’t be restricted simply to Earth. Rather, people will want to visit their favorite sites while cruising around the rings of Saturn with friends or relaxing at the (inevitable) Mercury tanning facility.
When the galaxy is our playground, marketers, analysts and webmasters will want to understand location use beyond Earth. For example, if you had a chain of taco stands and noticed many users visiting your website from the Mars outpost, well, that might help you make a business case to begin expanding your business to serve Mars colonists.