In the movie 2001 A Space Odyssey, humans have established a base on the moon. One day a strange black monolith is found. This monolith is obviously the product of some advanced civilization, but nobody knows it's purpose. To find out, a spaceship named the Discovery is sent to the planet Jupiter, from which the signals appear to originate, with a crew of two astronauts and HAL 9000, a super-intelligent computer who seemingly goes berserk, and after killing one of the astronauts, takes the ship on a wild journey through time and space. The remaining astronaut, after aging about fifty years, ends up in an ornately furnished hotel room. Audiences and film critics alike debate the meaning, and are unable to come to a conclusion. Human nature having difficulty with ambiguity, a sequel is eventually made called 2010, that explains some of the questions that were left open by the original film. A second spaceship is sent to Jupiter to discover what happened to the first one. Though the ending isn't completely clear, it appears that some form of extra-terrestrial intelligence was involved. Then a message is received by the scientists monitoring the progress of the mission. It says simply: “All these worlds are yours except Europa (Europa is a satellite of Jupiter). Attempt no landing there”.
Arthur C. Clarke, who wrote the novel on which the original film was based, has long been regarded as one of the greatest science-fiction writers, but it new looks like he was a bit of a psychic as well. NASA recently announced a plan to send a robotic spacecraft to Europa, with the tentative name of the Europa Clipper, around the year 2025. This spacecraft would go into orbit around Jupiter but would concentrate on studying Europa, a 1900-mile wide satellite of the giant planet. The reason scientists are so interested in Europa is because plumes of water vapor have been seen erupting from the moon's south pole. Planetary scientists believe that Europa may be covered by an ocean of water surrounded by a thin crust of ice, which would make it the only body in the entire solar system, other than Earth, to have a significant amount of water, which is one of the basic building blocks of life as we know it. Though Europa, being much further away from the Sun than we are, has a temperature of several hundred degrees below zero, life has been found on Earth existing in environments that have previously thought to be impossible, such as volcanic vents on the ocean floor, so it is certainly possible that life could exist on Europa as well.
One wonders, though, what would happen if the Europa Clipper does run into, not just life but intelligent life, as the Discovery did in 2001. Evidently, the aliens, or whatever they were, weren't too happy about being bothered. One can only hope that these aliens will be more friendly, or if not, at least that their weapons aren't that much more advanced than ours.