Extraterrestrial liquid water Extraterrestrial liquid water Extraterrestrial liquid water (from the Latin words: "extra" ["outside of, beyond"] and "terrestris" ["of or belonging to Earth"]) is water in its liquid state that naturally occurs outside Earth. It is a subject of wide interest because it is recognized as one of the key prerequisites for life as we know it and thus surmised as essential for extraterrestrial life. With oceanic water covering 71% of its surface, Earth is the only planet known to have stable bodies of liquid water on its surface, and liquid water is essential to all known life forms on Earth. The
Natural gas in the United States the oil and the gas are treated separately. Gas flows through a gathering system into a pipeline to a gas processing plant. As of 2014, there were 189,000 miles of interstate natural gas pipelines in the United States Natural gas has a variety of chemical constituents that must be removed or diluted with other gas to achieve consistent pipeline quality. Pipeline gas specifications vary from line to line, but generally the gas must contain no appreciable hydrogen sulfide (which is toxic), less than a few percent carbon dioxide (carbon dioxide reacts with water to form carbonic acid, which is corrosive