Yet unlike on earth, this submarine will need to withstand extreme cold temperatures of around -290 degrees Fahrenheit (-179 Celsius), and greater pressures than regular sea water.
These are hydro thermal vents and they spout a super heated cocktail of minerals and chemicals from deep within the earth crust. At temperatures up to four hundred degree Celsius.
And so when you're in an airline and you're looking out, you don't naturally think of the wind going past at 500 miles an hour and it's minus 50 out there and there's not enough air to breathe.
But as it rises, the temperature starts to drop again, because the atmosphere gets cooler as you go higher - by roughly one degree centigrade for every 100m of altitude.
So in an airliner, and you're looking out, you don't naturally think of the wind going past at 500 miles an hour and it's minus 50 out there and there's not enough air to breathe.
So by the second half of the 20th century, Celsius became popular in many parts of the world, when many English-speaking countries began using the metric system.