Gold star for Japan. The nation says that it has extracted gas from methane hydrate, the first time that’s been done in history. What does that mean? Methane hydrate is a frozen “cage” of water and methane, and can be a possible source of energy. Offshore deposits like the one about 30 miles away from Japan’s main island can potentially be a monster reservoir of methane. There is an environmental caveat, though: they’re pretty unstable under water.