Everyone, from casual dreamers to top scientists, has long theorized the notion that we are not the only intelligent life forms in existence. In this quest, scientists usually focus on planets that have conditions that are considered capable of supporting life; the main one of these qualities is water. While seventy-one percent of the Earth’s surface is covered in water, it is currently undiscovered whether any other planets in the universe also contain liquid water.
However, this past week, scientists at NASA have discovered new information about an ocean of ice on the moons of Jupiter and Saturn, thanks to the latest data obtained from the Cassini spacecraft. Europa, one of the moons of Jupiter, is said to potentially contain even more water than Earth, which is supported by the many features that look like ice rafts frozen into the surface. Even more interesting is that, below these ice rafts, there is said to be large oceans containing twice as much liquid water as on Earth.
This notion, that liquid water may exist below the surface of Jupiter, was further reinforced in both 2014 and 2016 when the Hubble telescope observed water vapor plumes coming from the south pole of the planet. Photos from Jupiter’s largest moon, Ganymede, have shown pattern markings on its surface indicating that veins of ice used to exist. The auroras of Ganymede also have contributed evidence showing that there may also be oceans of salt water similar to the ones found on Earth deep below the surface.
What is even more staggering is that the giant ocean on Ganymede is estimated to contain up to four times the amount of salt water contained in all the oceans found on Earth combined. The second largest moon of Jupiter, Callisto, also shows promising signs of having a salt-water ocean beneath the surface. Scientists were able to determine this by analyzing the magnetic field patterns of Casllisto’s orbit around Jupiter.
Several of Saturn’s moons have also exhibited similar signs to those of the moons of Jupiter indicating the presence of water. In 2005, one of Saturn’s moons, Enceladus, was photographed spewing what was, at the time, mysterious plumes. It was not until this past week that scientists were able to use an Ion and Neutral Mass Spectrometer (INMS), a type of instrument that analyzes gases, to confirm that these plumes had a high level of hydrogen present, indicating that water vapor was present.
Another component essential to life is a source of energy. While the Cassini spacecraft is not built to detect signs of life, Hunter Waite, the lead scientist of the Cassini research mission, did note that the recent data showed some of the conditions on Saturn are ideal for microbes to thrive. In 2020, NASA plans to expand its mission to discover more about these ocean worlds in its planned Europa Clipper mission. While we may be a far way away from discovering life on another planet, we are getting much closer to finding planets that support life as we know it.