The bottom of the Mariana Trench is the deepest point of our oceans and is known as the "Challenger Deep", and lies at a depth of around 11km (6.8 miles).
Category - Ocean Science
By playing the sounds of a healthy coral reef underwater, young coral fish can be lured to return to a damaged reef. There they can help restore the ecosystem.
Thanks to the tireless work of Sir David Attenborough, our focus has slowly shifted from the sky to an immense local mystery, the undiscovered depths of the ocean.