|North pole of Mercury with icy areas marked in yellow Image NASA APOD|
In the beginning God created the heavens and the earth. Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters.
Giving scientific explanation to the presence of water on planet Earth is a real challenge.
It has been suggested that meteorites hitting the surface of Earth are an important and perhaps the main source of water found on our planet. The discovery of icy planets orbiting the outer giant gas planets in our Solar system gives credence to such a view - we know that "there is waterout there".
The recent discovery of water in planet Mercury by MESSANGER cameras is illustrated in the APOD image above. The region of north pole where "radar bright" reflections suggest the presence of ice is always in the shade and colder than -280o F, -173o C. Yellow color is used in the photo to mark crater walls that may contain frozen water.
This discovery of water in Mercury adds credibility to the theory that water may be transported around in the Solar system by meteorites and that a large heavenly water-carrier may have brought the water that covers most of Earth's surface.
Many questions remain, however. I think that particularly important is the fact that the geology of the tectonic plates under Earths' oceans is different from the geology under continents.