Water vapor on Rosetta's target comet significantly different from that found on Earth
Thursday, December 11, 2014 - 15:31
in Astronomy & Space
ESA's Rosetta spacecraft has found the water vapor from its target comet to be significantly different to that found on Earth. The discovery fuels the debate on the origin of our planet's oceans. One of the leading hypotheses on Earth's formation is that it was so hot when it formed 4.6 billion years ago that any original water content should have boiled off. But, today, two thirds of the surface is covered in water, so where did it come from? In this scenario, it should have been delivered after our planet had cooled down, most likely from collisions with comets and asteroids.