Europa may be the most promising place in our solar system to find present-day environments suitable for some form of life beyond Earth.
Scientists are almost certain that hidden beneath the icy surface of Europa is a salty-water ocean thought to contain twice as much water as Earth’s oceans combined. And like Earth, Europa is thought to also contain a rocky mantle and iron core.
There is very strong evidence suggesting Europa's ocean is in contact with rock. This is important because life as we know it requires three key basic "ingredients": liquid water, an energy source, and organic compounds to use as the building blocks for biological processes.
Europa could have all three of these ingredients, and its ocean may have existed for the whole age of the solar system, long enough for life to begin and evolve there.
10 Need-to-Know Facts About Europa
Familiar Size
Europa is slightly smaller than Earth’s Moon and barely one-quarter the diameter of Earth itself.
A Darker Realm
Europa orbits Jupiter, the fifth planet from the Sun. Jupiter orbits the Sun at a distance of about 484 million miles (778 million kilometers).
Locked On
Europa rotates once on its axis and completes one orbit of Jupiter every 3.5 Earth days, so the same side of Europa always faces Jupiter.
Reddish Bands on Europa
Icy Moon
Europa's surface is mostly solid water ice. It is crisscrossed by fractures.
Bring Your Spacesuit
Europa has an extremely thin oxygen atmosphere — far too thin for humans to breathe.
Nothing in its Orbit
Europa has no moons of its own.
Ringless
Europa has no rings, but some moons in the solar system may have had rings in the past.
Popular Destination
Europa has been visited by several spacecraft and more missions are planned.
All These Worlds
Abundant liquid water, energy and the right chemical elements make Europa one of the best places in the solar system to seek present day life beyond Earth.
Don't Forget a Towel
Europa's subsurface ocean might contain more than twice as much water as Earth's oceans combined.
Europa Rising
Pop Culture
Europa has been featured in short stories, comics, and novels, with perhaps the best-known being the Arthur C. Clarke novel “2010: Odyssey Two,” which was also adapted for film.
More recently Europa was the setting for the 2013 film “Europa Report,” and it was featured in an episode of the animated television show “Futurama.”
The moon has also been the setting or subject of several video games, including “Call of Duty: Infinite Warfare” and “Galaga: Destination Earth.”
Read More