>It may be some kind of hydrogen-rich fuel (methane or ammonia)... Unlikely to be ammonia. Ammonia is dangerous in the kind of concentrations that would make

>It may be some kind of hydrogen-rich fuel (methane or ammonia)... Unlikely to be ammonia. Ammonia is dangerous in the kind of concentrations that would make it useful for fuel. When ammonia was used in refrigeration whole families would occasionally die when their refrigerator sprang a leak.