Europa is an important moon (despite being one of more than 60 orbiting Jupiter) because scientists believe it features something we know to be invaluable in the formation of life as we know it — liquid water. If it exists, this massive ocean sits under the moon's icy crust, and may actually have more water by volume than all of Earth's oceans put together.
Along with the new image, NASA has released a video explaining what we know about Europa — and what we hope to learn:
Europa is a cold place: At 485 million miles from the sun, its surface temperature is never higher than -260 degrees Fahrenheit. And at its poles, the moon is some 100 degrees colder. So how could it maintain liquid water?
Scientists believe that the tidal force that Europa is subjected to from orbiting Jupiter is so strong that it provides enough friction energy to keep water liquid — even as the water on the surface hits incredibly low temperatures and freezes. It's possible that a salty ocean is able to interact with the rock of the sea floor, which could provide the kind of chemical energy that begets life.
Maybe we'll learn more about Europa soon. Slate astronomy blogger Phil Plait suggests that this image and video release may be intended to drum up support for a new NASA mission to the icy moon. It could be that our next big orbiter project will help us confirm the existence of an alien ocean.