© Universal History Archive / Getty ImagesEnceladus, the sixth-largest moon of Saturn.
NASA scientists have detected hydrogen from hydrothermal vents in ice plumes from Saturn's ocean-bearing moon Enceladus in conditions which they say could have led to the rise of life on Earth.
The discovery makes Enceladus the only place beyond Earth where scientists have found direct evidence of a possible energy source for life, according to the findings published in Science.
Chris Glein, Cassini INMS team associate at Southwest Research Institute (SwRI), said during the news conference that they believe the hydrogen is produced by a chemical reaction between warm water and rocks.
The team says the moon has the sources needed for life, but what needs to be established is if it has enough time to evolve life.
"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," said Hunter Waite, lead author of the Cassini study.
Meanwhile, the Hubble telescope captured more evidence of water based plumes on Jupiter's icy moon Europa. NASA said a similar plume candidate was captured at the same location in 2014 and 2016. The plumes also correspond with a relatively warm region on Europa's surface observed by the Galileo spacecraft.
William Sparks, an astronomer with the Space Telescope Science Institute in Baltimore, said the results are "intriguing as they found a repeating plume candidate at a position of a Thermal anomaly."
Mary Voytek, senior astrobiology scientist at NASA Headquarters said there might not be life on either moon, adding, if there is life, it might not be very active. She said her money is on Europa, when asked by a reporter which moon was more likely to host life.
NASA's upcoming Europa Clipper mission planned for launch in the 2020s will continue the search for life beyond Earth, and will study Enceladus with advanced equipment.
"These ocean worlds have just been discovered - we need to probe them because they are one of the best locations that may harbor life today," the space agency said at the close of Thursday's announcement.
My belief is that all planets are sentient. Having perceived what humanity has done to this planet no other celestial body will accept us. We need to learn how to understand and help maintain our own environment first.