Jupiter’s moon Europa is one of the 79 icy bodies orbiting the largest planet in our solar system. Europa has been an object of keen study since NASA’s Voyager 1 first shot past Jupiter in March 1979. Astronomers at NASA’s Goddard Space Flight Center have now for the first time confirmed the presence of water vapour in Europa’s atmosphere.
Until recently, scientists have speculated liquid water could be trapped under Europa’s mile-thick outer layer of ice.
The moon could potentially be home to an alien ocean twice as big as Earth’s.
Liquid water is a key building block of life as we know it and is at the forefront of NASA’s hunt for extraterrestrial life.
If liquid water does exist just beneath Europa’s surface, it opens up the possibility of simple microbial life developing on the Jovian moon.
NASA planetary scientist Lucas Paganini said: “Essential chemical elements – carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur – and sources of energy, two of three requirements for life, are found all over the solar system.
“But the third – liquid water – is somewhat hard to find beyond Earth.
“While scientists have not yet detected liquid water directly, we’ve found the next best thing: water in vapour form.”
Since Voyager’s flyby of Jupiter 40 years ago, scientists have speculated Europa was spewing large geysers of liquid water out into space.
But without a space probe to make up-close observations of Europa’s surface, NASA has only been able to observe the moon from Earth.
The latest discovery was made from the W.M Keck Observatory on top of Hawaii’s Mauna Kea volcano – one of the biggest telescopes in the world.
NASA’s astronomers spied the presence of molecular water in Europa’s atmosphere, in quantities large enough to fill an Olympic-size swimming pool.
The discovery was reported in a paper published in the journal Nature Astronomy on November 18.
The astronomers found the water vapour could fill a swimming pool with about 5,202 pounds or 2,3600kg per second.
Dr Paganini said: “For me, the interesting thing about this work is not only the first direct detection of water above Europa but also the lack thereof within the limits of our detection method.”
Astronomer Lorenz Roth who co-authored the study said: “This first direct identification of water vapour on Europa is a critical confirmation of our original detections of atomic species, and it highlights the apparent sparsity of large plumes on this icy world.”
Asteroid danger: 100% certainty of impact warns space expert [INTERVIEW]
Humans will struggle to survive a supervolcano eruption [ANALYSIS]
Britain could be hit a by a monstrous tsunami [COMMENT]
However, the water appears to be venting from Europa infrequently and in varying amounts.
NASA’s team only made one detection of the water vapour over the course of 17 nights between 2016 and 20017.
The researchers also believe they will need to get really close to the Jovian moon to truly understand how the water is seeping into Europa’s atmosphere.
NASA’s Avi Mandell said: “We performed diligent safety checks to remove possible contaminants in ground-based observations.
“But, eventually, we’ll have to get closer to Europa to see what’s really going on.”
Luckily for Dr Paganini’s team, NASA aims to launch the Europa Clipper space probe towards Jupiter by 2023.
The spacecraft will enter an orbit around Europa to perform between 40 and 45 close flybys.
Clipper will study the moon’s atmosphere and take snapshots of Europa’s mysterious surface.
If there are any large vents on the planet releasing water into space, odds are Clipper will find them.
NASA also hopes to find potential landing zones for future Jupiter-bound missions.
The space agency said: “These efforts should further unlock the secrets of Europa and its potential for life.”