604
Google is making a map of methane leaks for the whole world to see
(www.businessinsider.com)
This is a most excellent place for technology news and articles.
Google detecting farts from space.
Adds your fart map to your monthly gmaps timeline!
I think aside from Cattle a large source of Methane Emissions would be Flare Stacks from Pumpjack Locations. Technically it's illegal to burn off the excess natural gas, but the punishment is a fine.