THE SHORT ANSWER
The deepest point, the Challenger Deep, is about 10,935 m down. If you dropped Mount Everest (8,849 m) into it, there would still be about 2 km of water above the top.
Big facts, for scale
- Sunlight barely gets past 200 m. Below that it's dark, and between 200 and 1,000 m about 4 out of 5 animals make their own light.
- "Marine snow" falls all the time in the deep: tiny bits of dead plants, animals and poop.
- We have better maps of Mars than of most of our own ocean floor.
- Deep submarines sink on purpose and drop steel weights to come back up, like the Trieste in 1960. The pressure at the bottom is over 1,000 times what we feel at the surface.
Watch the episode
Tiny Human vs. the Mariana Trench goes out on TikTok, Instagram, Facebook and X. Times are shown in yours.
For grown-ups and teachers
Ask: why do deep-sea animals make their own light? Compare the trench with the tallest mountain using a scale drawing.
Sources
- NOAA Ocean Exploration: the Challenger Deep, light in the deep sea, marine snow
- Everest height: 8,848.86 m (China–Nepal survey, 2020)
Facts last checked 4 November 2026. Tiny Human's art and voices are made with AI tools; every fact is checked by a person against the sources above.
