A spacecraft can simply fly by Europa and study its watery plumes by taking samples of its atmosphere, a new study suggested.
Europa's massive plumes of water vapor have already stopped erupting. But according to researchers from the Southwest Research Institute in San Antonio, Texas, the plumes can still be studied by sampling the constantly shifting chemical patterns in the atmosphere caused by the plumes themselves, New Scientist reports.
"Those are free samples: we can just fly by and we can grab some of that material," Cynthia Phillips at NASA's Jet Propulsion Laboratory in California, said in a statement. "That's our best way of understanding what's going on - not just at Europa's surface but, in the case of plume sampling, the subsurface - from orbit."
In 2012, the Hubble Space Telescope found evidence that plumes of water vapor were vented off Jupiter's icy moon, which is indicative of subsurface oceans beneath the moon's surface. An image of the water plumes being expelled again from Europa was presented by NASA's Hubble team in September. According to scientists, the ocean could be one of the best places to look for life in the solar system.
However, the problem is that Europa seems to expel water plumes at irregular intervals. But the researchers have found a way to sample the plumes even if they are not active when a spacecraft flies past the Jovian moon.
According to study, Europa's gravity may pull material from the plumes back to the surface, creating a layer of frost. Eventually, some of the particles will be thrown off the surface by evaporating or by being thrown upwards when charged particles from Jupiter's magnetosphere hit Europa's surface, the researchers said.
The particles could fill Europa's atmosphere, producing constantly shifting chemical patterns, and could provide insights about the water plumes and the composition of the surface even if the eruption has stopped. According to study author Ben Teolis, they could calculate where the particles came from and map them out on the moon's surface.
"The potential to see the spatial distribution of the molecules and the change in the atmosphere over time is pretty spectacular," Teolis told New Scientist. "Understanding this problem is a major element in nailing down the composition of Europa's subsurface ocean, and the potential for it to support life."
The discovery of the water plumes presents a great opportunity for proposed missions that will explore Europa and probe its oceans to find evidence of life. NASA is working on a flyby mission to Jupiter's moon, which is targeted for launch in 2020.