It seems there are few places in the solar systems without some amount of water, whether liquid or solid. There’s even a small amount of water vapor on Venus, something like 20 parts-per-million. And every time a source of liquid water is found or suggested, it brings up the chances of life on that world because of the way water acts as a solvent – facilitating the metabolic processes at the most basic level of life. That’s why the hunt for extraterrestrial life (quite doubtfully of an intelligent sort, though we’ve found some quite remarkable octopuses on Earth) has turned from distant solar systems to our own cosmic backyard.
Here’s the breakdown of all the water we know about in the solar system, and what form it comes in.
All But Confirmed:
Europa has been the biggest contender for life for years now, with a craggy icy crust hinting in almost every way at an ocean below. Thanks to the tidal effects from Jupiter (friction inside the moon created by the pull of the planet’s gravity), the water would be kept liquid and possibly even warm below the icy crust, helped by possible hydrothermal vents.
There’s been some evidence of ice geysers shooting from the surface of Europa, as well as evidence that the ocean could have Hadley Cells—warm water radiating from the moon’s equator. Europa could provide the possibility not just for life, but, if the conditions were just right, even complex life.