Just like in the case of Jupiter's biggest moon, Ganymede, old data from the Galileo mission that ended in 2003 has yielded a new exciting discovery about Europa.
As the Inquisitr reported earlier today, NASA announced a major update on Jupiter's icy moon. The big reveal is based on a fresh analysis of the flight software from Galileo's 1997 flyby of Europa and points to a giant water plume erupting on the moon's surface, the agency stated in a news release.
According to a study published today in the journal Nature Astronomy, the Galileo spacecraft detected what seems to be a massive water plume shooting out into space from Europa during one of its 11 flybys of Jupiter's moon conducted between 1995 and 2003.
Furthermore, the new analysis reveals that the Galileo probe may have actually passed through the giant water plume in 1997, when the spacecraft came as close as 124 miles (200 km) from Europa's surface.
Robert Pappalardo, from NASA's Jet Propulsion Laboratory in Pasadena, California, says that, in view of the new findings, Europa's prospective water plumes just got "real."
"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."The likely water plume was signaled by a thermal anomaly picked up by the probe's Plasma Wave Spectrometer close to the moon's equator, in the middle of a "hotspot" area stretching over 200 miles (320 km). The study shows that the spacecraft's instrument detected two critical phenomena in this area: a significant change in Europa's magnetic field and a surge of ionized gas hinting at a large increase in density of the moon's plasma.
Using computer simulations, the research team determined that those observations were consistent with the presence of a water plume on Europa.
"The result that emerged, with a simulated plume, was a match to the magnetic field and plasma signatures the team pulled from the Galileo data," NASA pointed out in the news release.
Study lead author Xianzhe Jia, from the University of Michigan's Department of Climate and Space Sciences and Engineering, told Space.com that the new analysis of the Galileo data offers "compelling independent evidence that there seems to be a plume on Europa."The 20-year-old data supports the findings of NASA's Hubble Space Telescope, which uncovered clues of possible water plumes in the same "hotspot" on Europa during its observations of Jupiter's moon in 2014 and 2016.
"The data were there, but we needed sophisticated modeling to make sense of the observation," Jia explained in the NASA news release.
These results add to the body of evidence that Europa may have a global ocean tucked beneath its icy surface, just like Saturn's moon, Enceladus. This increases the odds that the two moons could possess the necessary ingredients to harbor life.
Along with Enceladus, Europa is "one of the most promising places in the solar system to search for life," NASA stated in a previous statement.
To verify this monumental discovery, the space agency is planning a new expedition to Jupiter's moon. With a targeted launch date set for June, 2022, the Europa Clipper mission will perform 40 to 45 flybys of the moon to study its icy crust and giant subsurface ocean. Although slightly smaller than Earth's moon, Europa is estimated to hold twice as much water as our planet underneath its frozen surface.
"There now seem to be too many lines of evidence to dismiss plumes at Europa," said Pappalardo, who is a project scientist for the Europa Clipper mission.
The Clipper aims to find out whether Europa's plumes are coming from its subsurface ocean and to gather samples that would help uncover how the plumes are produced.