NASA confirms water vapor on Europa in major breakthrough in search for extra-terrestrial life
While scientists have not yet detected liquid water directly, experts say they have found the next best thing: water in vapor form
NASA scientists have now confirmed the presence of water vapor in Europa (Image credit: NASA/JPL-Caltech/SETI Institute), one of Jupiter’s 79 moons, for the first time. This discovery makes the icy moon one of the strongest candidates to harbor life.
To support life, an object needs to have the essential chemical elements -- carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur -- and sources of energy, components that are already found all over the solar system. But what the solar system appears to lack is the third requirement, liquid water, which is somewhat hard to find beyond Earth, study lead author Lucas Paganini, a planetary scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and American University in Washington, D.C., said in a statement.
“While scientists have not yet detected liquid water directly, we’ve found the next best thing: water in vapor form,” he added.
NASA's interest in Europa began over four decades ago, when the Voyager spacecraft hurtled past the object, providing the first hint that the moon may contain water. Scientists have since gathered evidence that liquid water is present under the icy moon's surface, thanks to the Galileo spacecraft which reached Europa in 1996.
Taking a closer look at the data from Galileo, helped Margaret Kivelson, professor emerita of space physics at the University of California, Los Angeles and her team realize that Galileo flew through a plume -- liquid that was piercing through the moon's icy shell and bursting out, erupting like a huge geyser.
Galileo provided evidence that there could be an ocean on another space body, for the first time. But, until now, no one has been able to confirm the presence of water in these plumes by directly measuring the water molecule itself, NASA said in a statement.
So this time, the research team observed Europa for 17 nights between 2016 and 2017 using the W. M. Keck Observatory in Hawaii -- one of the biggest telescopes in the world. And in one of those nights, they detected a faint yet distinct signal for water vapor. They observed that Europa was releasing 5,202 pounds of water per second, which could fill an Olympic-size swimming pool within minutes, according to NASA. This discovery adds more weight to the idea that an ocean of liquid water or slushy ice is present beneath the moon's ice surface.
To gain more insights on the inner and outer workings of this possibly habitable world, scientists are looking forward to the forthcoming Europa Clipper mission, which is set to investigate whether the icy moon could harbor conditions suitable for life after its launch in the mid-2020s.
When it arrives at Europa, the Clipper orbiter will conduct a detailed survey of Europa’s surface, deep interior, thin atmosphere, subsurface ocean, and potentially even smaller active vents, as per NASA. These efforts, the scientists believe, could unlock the secrets of Europa and its potential for life.