Marine Life · 23 Oct 2025
Imagine the surface of the moon — dark, alien, and totally untouched. Now imagine a place on Earth that's even more remote: the Mariana Trench. Plunging nearly 11 kilometres deep, this trench in the Pacific Ocean contains the Challenger Deep, the single deepest point on our planet. It's an area of crushing pressure, freezing temperatures, and total darkness — a world we call the hadal zone.
For decades, getting there was harder than space travel. But a few brave explorers in extraordinary submersibles have plunged into this midnight world, changing what we know about life on Earth.
The first-ever successful trip to the bottom was a monumental feat of daring and engineering. On 23 January 1960, oceanographer Jacques Piccard and U.S. Navy Lieutenant Don Walsh crammed themselves into the Swiss-designed bathyscaphe, the Trieste.
Think of the Trieste as an underwater blimp. To stay afloat, it used a massive float filled with petrol — not for fuel, but because petrol is lighter than water and can't be compressed by pressure. The two men sat inside a small, incredibly strong steel sphere built to resist the immense forces — over 1,000 times the pressure at the surface.
The descent took almost five hours. When they finally landed on the seabed, they spent 20 minutes looking out a tiny window. Their surprising discovery? They saw signs of life, proving that the deepest ocean floor wasn't a dead wasteland as many scientists had previously thought. This pioneering dive showed that humans could indeed reach the very bottom of the world.
Fifty-two years after the Trieste, Oscar-winning filmmaker and explorer James Cameron took his own plunge. He piloted a solo, vertical torpedo-like submersible called the Deepsea Challenger.
Cameron's machine was a massive technological upgrade. It used advanced, lightweight materials to handle the pressure, and carried high-definition 3D cameras and tools to collect samples. This time the trip down was much faster, and Cameron had the luxury of spending three hours exploring the pitch-black floor, collecting specimens and filming the otherworldly landscape.
The explorations by the Trieste, Deepsea Challenger, and subsequent robotic vehicles have taught us that the deepest trenches are full of life, not empty.
While the discovery of thriving life is incredible, a sobering find by later explorers revealed that even the Challenger Deep is not isolated from humanity. Amidst the strange, unique creatures, explorers found evidence of plastic pollution — a powerful reminder that our actions on the surface reach every corner of the planet, no matter how deep or remote.
The manned submersibles that pierced the "midnight zone" didn't just break records; they revealed a vital, mysterious world that still holds countless secrets about life and our own planet.