Europa is thought to possess a vast sub-surface ocean beneath its thick icy crust, kept in a liquid state via tidal interactions with the gas giant. Possibly containing three times the volume of water held in Earth’s oceans — and because on Earth, where there’s water, there’s life — astrobiologists hypothesize that Europa’s ocean might be quite a cozy place for biology to gain a foothold.
“Europa’s ocean, to the best of our knowledge, isn’t that harsh of an environment,” said astrobiologist Kevin Hand, JPL’s Deputy Chief Scientist for Solar System Exploration, at a special JPL “Icy Worlds” media event on Monday.
Although Europa’s ocean may be up to 100 kilometers (62 miles) deep, the conditions at the bottom of that monstrous abyss may be akin to the environment at the bottom of Earth’s comparatively shallow Mariana Trench, the deepest region of the Pacific Ocean, which is 11 kilometers (6.8 miles) deep. Complex biology has evolved in Mariana’s cold, dark environment, so it’s not such a stretch to think that if there is life in Europa’s ocean, it may also be thriving, extracting energy not from the sun (via photosynthesis), but from chemosynthesis near hydrothermal vents.