A “devil” comet’s water is strikingly similar to the water on Earth, researchers have discovered. The finding supports the idea that water was brought to our planet through comet impacts, helping set the stage for life to evolve, the team reported Aug. 8 in the journal Nature Astronomy. … This is especially significant because previous measurements of the water on Halley-type comets revealed different D/H ratios, casting doubt on the theory that comets could have brought water to Earth. This new discovery, by contrast, strengthens the theory.