How did the ocean form?

Answer 1

Formation of the OceanThe current theory holds that after the Sun formed, there was a very large disk of dust and gas orbiting it. In this disk were all the elements that we see today, which were themselves formed in the furnaces of other stars. Anyway, it lumps together because of gravity and eventually pulls itself into balls, which then eventually become planets. Water was also present in this disk, and continued to be delivered to Earth in the form of comets after our planet had solidified. It's present mostly on the surface because when the planet was first formed, it was molten rock and very volcanically active. The water inside the planet was thus ejected as steam, but held in the atmosphere by Earth's gravity.

-Wes

Answer 2

by a thick blanket of hydrogen:)