by flagamuffin

Measurements from Rosetta’s Rosina instrument found that water on comet 67P /Churyumov-Gerasimenko contains about three times more deuterium – a heavy form of hydrogen – than water on Earth.

The discovery seems to overturn the theory that Earth got its water, and so its ability to harbour life, from water-bearing comets that slammed into the planet during its early history.

If this is confirmed, it's kinda huge.