Old Data From NASA's Galileo Shows Evidence For A Plume In Jupiter Moon's Europa

NASA found more evidence of water plumes in Jupiter's moon Europa by poring over 20-year-old data from the Galileo probe in the 1990s.

Water Plumes In The Moon Europa

In Earth, water is indicative of life. So in the search for extraterrestrial beings outside of the planet, astronomers have kept an eye out for signs of water.

A year or two ago, NASA astronomers were going over the data from the Hubble Space Telescope when they spotted what appeared to be plumes of water shooting from the moon's surface, according to a report from NASA.

"This wasn't planned out," study author Xianzhe Jia from the University of Michigan explains to Gizmodo. "It just so happened that the spacecraft passed through a region where we saw plumes. It was fortuitous."

Following this discovery, researchers reviewed data from the Galileo mission that also flew over Jupiter in the 1990s.

A new study published in the journal Nature Astronomy confirms the presence of water plumes. Researchers say that the data suggests that the probe flew through a plume in 1997 in the same spot where Hubble caught a glimpse of plumes in 2016.

With the high-resolution magnetometer data from the Galileo mission, the scientists found a brief, localized bend in the magnetic field that's consistent with ionized plumes from Saturn's Enceladus. Data from Galileo's Plasma Wave Spectrometer also supported the existence of plumes in Europa.

Backed by a new 3D model created using both sets of data, the study's strong support of the water plumes bodes well for future missions in Europa and beyond. 

"There now seem to be too many lines of evidence to dismiss plumes at Europa," Robert Pappalardo, Europa Clipper project scientist at NASA's Jet Propulsion Laboratory, points out in a statement. "This result makes the plumes seem to be much more real and, for me, is a tipping point. These are no longer uncertain blips on a faraway image."

Europa And Its Potential

Water plumes support the idea that underneath Europa's ice-crested surface, there's a massive expanse of subterranean ocean. If there's water along with energy necessary for the plumes to erupt, then life could be possible in this Jupiter moon.

The Europa Clipper mission is expected to shed more light on the elusive moon with rapid, low-altitude flybys from its orbit. It's targeted to be launched in space by June 2022.

Furthermore, a plume makes it possible for spacecrafts to get a sample of the subterranean water even without drilling onto the surface or landing on the planet.

"If plumes exist, and we can directly sample what's coming from the interior of Europa, then we can more easily get at whether Europa has the ingredients for life," Pappalardo continues. "That's what the mission is after. That's the big picture."