The alien world covering most of our planet — its depth zones, coral reefs, giants, strangest creatures, and phenomena like glowing seas and tides. Learn it because it's the closest thing to alien life we can visit, and it changes how you see the blue half of the planet.
The ocean covers **71% of Earth**, yet we've explored only a sliver of it — we have better maps of Mars than of our own seafloor. It's the closest thing to an alien world we can actually visit. It's organized by **depth**. Sunlit shallows host the riot of life on **coral reefs**; below them lies…