Europa is one of the largest moons of Jupiter, and also one of the most studied. It is a ball located 650 million kilometers from Earth, which, if we got closer, would surely remind us a lot of the Arctic. Europe is frozen. Yet perhaps, as in the Arctic, all that ice is floating on liquid water.
The bodies located so far from the Sun, 800 million kilometers, are usually completely frozen. So why do scientists believe that the interior of Europa could be a rich ocean, perhaps teeming with life ?
The reason is that there are geysers, pressurized water that is thrown off the surface of Europa, through its thick layer of ice, between 20 and 50 kilometers thick. This leads to think that there is some force operating in Europe. In fact, the study of these feathers of material ejected over Europe could give us clues about what is inside, and thus start the search for life without drilling it.
Since its nucleus a priori must be inoperative, since it is a satellite, it is likely that the immense gravity of Jupiter, the most massive and oldest planet in the Solar System, is working its magic so that hidden forces operate inside of Europe. And this interaction may be heating its interior and thus allowing liquid water to exist, with the ideal conditions for extraterrestrial life to develop.
It is no wonder that complex creatures can live hidden under a large layer of ice. It has already happened on Earth: just before the largest explosion of life in its history was unleashed (the Cambrian explosion), about 650 million years ago a period of freezing took place, the Earth snowballing: the longest Ice Age of the history of planet Earth.
The scientists’ hypothesis, therefore, is that it is quite possible that an entire ecosystem of microbes, crustaceans, squids … is hiding under the ice of Europa right now. If true, the discovery of the first extraterrestrial creatures in history, and also in our own Solar System, would be a true milestone for humanity.
NASA plans to send a spacecraft to drill through Europa’s ice in 2020 to see if the astrobiologists’ hypothesis is true. Until then, the possibility of life in Europe will remain an intriguing mystery.
