How many oceans are there on planet Earth, 5 or 6?

At present, there are five oceans that exist on the planet. Scientists from around the world have now discovered evidence of significant water content between the Earth's upper and lower mantle.

Pacific ocean

Atlantic ocean

Indian ocean

Arctic ocean

Southern ocean

The study by the German-Italian-American scientific team, which was published in the journal Nature, claims that the 660 km beneath, lower mantle, is a potential sixth ocean. 

All photos credit: Pixabay