When the Cassini spacecraft made its pass by Saturn’s moon Enceladus, it recorded jets of water spraying from tiger stripe gashes on the moon’s icy surface, placing the colorless satellite at the top of the list of places to look for alien life.What the streams of water told astrobiologists was that there was an ocean underneath the planet’s uninviting surface, kept warm by tidal heating; the rotational energy that's dissipated as heat into the planet's interior. With that said, alien microbes in the ocean could be shot right out of the moon’s south pole onto NASA’s probe, without them even realizing it in the first place.NASA’s motto for a while now has been to, “Follow the water,” in order to continue its quest to find another form of life in the known universe. The search for water has sparked the recent interest in Mars, with its damp streaks of sand.

However, on Wednesday, Oct. 28, Cassini made its closest pass into the plumes of Enceladus, skimming only 30 miles above the moon’s surface. And while the spacecraft isn’t equipped with instruments that can capture the theorized microbes that NASA hopes to find, it has detected numerous molecules associated with life. In its multiple passes, the Cassini has recorded traces of water vapor, carbon dioxide, methane, molecular nitrogen, propane, acetylene, formaldehyde and traces of ammonia.

This illustration is a speculative representation of the interior of Saturn's moon Enceladus with a global liquid water ocean between its rocky core and icy crust. The thickness of layers shown here is not to scale.

(NASA/JPL-Caltech)

“ itself,” Cassini project scientist Linda Spilker told Astrobiology Magazine. “Those instruments can, however, make powerful measurements about the ocean and its potential habitability.”Scientists are also interested in the levels of hydrogen gas found in the moon’s plume, which would give them an idea of the amount of energy and heat being produced by the moon’s hydrothermal vents on the ocean’s floor.And, as NASA astrobiologist Chris McKay said, it’s as if someone had hung a sign on Enceladus reading, “Free Samples.” There’s no drilling to be done or need to do anything other than simply fly on by.Cassini’s final flyby of Enceladus on Dec. 19 will be an attempt to , according to NASA.The recon Cassini’s currently on will have a major impact on whether a return mission will be made. Even then, it will take years of work and X amount of dollars only to simply ring the doorbell to see if there’s something to answer our knock.

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