NASA: Europa may have plumes of water being jettisoned into space
NASA announced on Monday, Sept. 26, a discovery regarding the Galilean moon Europa. Hubble Space Telescope observations show the moon appears to be jettisoning plumes of water out into space.
Scientists have long held (and had the data to prove) that a subsurface ocean exists on the distant world – of which might be capable of supporting life.
The plumes appear to be ejecting water some 125 miles (200 kilometers) away from Europa before falling back to the moon’s surface. SpaceFlight Insider asked when a solid confirmation of these plumes might be possible.
“There are two things that would help. One would be repeated Hubble observations to continue to expand our understanding of the characteristics of this instrument. I think we could become confident with just Hubble observations,” William Sparks of the Space Telescope Science Institute (STScI) told SpaceFlight Insider. “The other thing that could potentially nail it would be for somebody else to come in with a completely independent observing technique and the results were found to be consistent.”
While there are many specifics that scientists do not yet understand concerning the dynamics involved on Europa, it is known the ocean that surrounds Europa contains two times the amount of water of Earth’s oceans.
Sparks’ team saw finger-like projections while viewing Europa as the moon orbited in front of its parent planet – Jupiter. Finding plumes actually was not what the team was originally looking into. They were working to determine if Europa has a thin, extended atmosphere, or exosphere.
The method used to determine whether Europa had either an atmosphere or exosphere was actually derived from those used to determine if exoplanets – planets around other stars – might have atmospheres.
“The atmosphere of an extrasolar planet blocks some of the starlight that is behind it,” Sparks said. “If there is a thin atmosphere around Europa, it has the potential to block some of the light of Jupiter, and we could see it as a silhouette. And so we were looking for absorption features around the limb of Europa as it transited the smooth face of Jupiter.”
Scientists working with Hubble actually made the observations of what could be plumes back in 2014. Software and other elements were required to optimize the data coming back from Hubble – which became a complex process.
Representatives present during Monday’s teleconference stated that NASA hopes to use the Hubble Space Telescope, which was used to discover the plumes that were emitting from the moon’s southern region, in tandem with the James Webb Space Telescope, which is currently slated to launch atop an Ariane 5 rocket in 2018.
“Hubble’s unique capabilities enabled it to capture these plumes, once again demonstrating Hubble’s ability to make observations it was never designed to make,” said Paul Hertz, director of the Astrophysics Division at NASA Headquarters in Washington. “This observation opens up a world of possibilities, and we look forward to future missions – such as the James Webb Space Telescope – to follow up on this exciting discovery.”
One potential plume was also noted along Europa’s equatorial region.
At present only the Saturnian moon Enceladus is known to have plumes of water that have been jettisoned out into space. These were discovered by the Cassini spacecraft which is currently in its last year orbiting the ringed gas giant.
The importance of the presence of geysers on Europa likely can’t be overstated. NASA and other space agency’s have expressed great interest in Europa and are planning missions to the icy moon. However, this would mean any lander would need to dig through miles of ice. Locations where the ocean on Europa is close, or even right at the surface, would mean that drilling would be rendered unnecessary.
“Europa’s ocean is considered to be one of the most promising places that could potentially harbor life in the Solar System,” said Geoff Yoder, NASA’s acting associate administrator for the agency’s Science Mission Directorate. “These plumes, if they do indeed exist, may provide another way to sample Europa’s subsurface.”
Video courtesy of NASA Goddard
Jason Rhian spent several years honing his skills with internships at NASA, the National Space Society and other organizations. He has provided content for outlets such as: Aviation Week & Space Technology, Space.com, The Mars Society and Universe Today.