A plume of water vapor has been seen once again on Europa, one of Jupiter’s moons, confirming the existence of water and suggesting that there may be life underneath the satellite’s icy exterior.

The plume was 62-miles high and occurred near the moon’s equator in February. It was larger than the one seen in the exact same location back in March 2014. The existence of water in Europa increases the expectations of finding alien life in a nearby environment, joining Enceladus, one of Saturn’s moons which may also harbor life.

Hubble, Saturn
These composite images show a suspected plume of material erupting two years apart from the same location on Jupiter’s icy moon Europa. Image credit: NASA.

The ingredients are right there in our solar system

One of the crucial factors behind the discovery is that the plume occurred in the exact same spot twice, which asserts that it cannot have happened by chance. This is leading researchers to look into effects that might cause it or any other natural cause.

NASA is now planning to send the Europa Clipper mission, which will orbit around Jupiter and fly at least 40 times near Europa. The probe will study the moon and its inner ocean, allowing scientists to confirm its ability to harbor life. If possible, Clipper will fly through the water plumes, following the example of the Cassini probe as it flew through Enceladus’ plumes.

According to Thomas Zurbuchen, NASA’s associate administrator for Science Mission Directorate at Headquarters in Washington, the results collected by the Cassini probe represented the closest humankind has ever gotten to identifying a place with the ingredients to sustain life. This also suggests that NASA’s efforts to find life have not been secluded, but rather interconnected in the quest for extraterrestrial life.

In the case of the Cassini mission, the probe identified hydrogen gas, which could be a chemical energy source for life. The plume on Enceladus’ surface appears to have originated from its hydrothermally-active seafloor.

The presence of hydrogen means that, if there are any microbes in the moon’s ocean, they could make use of the compound by combining it with the carbon dioxide present in the water, performing a process known as methanogenesis, producing methane as a byproduct and representing one of the primary ways how life formed on Earth.

“Although we can’t detect life, we’ve found that there’s a food source there for it. It would be like a candy store for microbes,” stated Hunter Waite, lead Cassini researcher.

Scientists agree that life requires liquid water, a source of energy for metabolic activities, and a coherent combination of chemicals, these primarily being carbon, hydrogen, nitrogen, oxygen, phosphorous, and sulfur. Enceladus has almost every single one of these ingredients, except for phosphorous and sulfur, although scientists believe they may be somewhere in its inner ocean, as the moon’s core is believed to be similar in its composition to meteorites that do contain both chemicals.

“The plumes on Enceladus are associated with hotter regions, so after Hubble imaged this new plume-like feature on Europa, we looked at that location on the Galileo thermal map. We discovered that Europa’s plume candidate is sitting right on the thermal anomaly,” stated to NASA’s press siteWilliam Sparks of the Space Telescope Science Institute in Baltimore, Maryland.

Source: NASA