It is known that people know more about deep space than about the ocean depths on our planet. The ocean jealously keeps its secrets and contains a lot of underwater places, information about which is almost non-existent.
One of these places until recently was the Mariana trench, although it was discovered more than 150 years ago.
The Mariana trench, or more correctly – the Mariana trench as it is quite a narrow recess, the lowest solid surface of the Earth, which is in the South-Western Pacific ocean, near the Islands of the same name.
In 1875, the sailors of the English ship "Challenger", measuring the depth of the ocean in these parts, found "a place without a bottom". The cable of the lot was sinking down kilometer after kilometer, and the bottom was still not reached. Finally, at the ninth kilometer, the descent of the cargo stopped. It became clear that the deepest crevice on Earth was discovered.