NASA revealed on Monday that the Hubble Space Telescope has found what appear to be water vapor plumes erupting from the surface of Europa, one of the 67 known moons of planet Jupiter.
Astronomers used Hubble to image what could be water vapor plumes erupting off the surface of the icy moon. The findings strengthen other Hubble observations that hint of geysers of water on Europa.
Astronomers may use the James Webb Space Telescope, which is set to be launched in 2018 to confirm the plume activity on Europa. The U.S. space agency is also formulating a mission with payload that may confirm the existence of plumes and study them in close proximity during flybys.
If the existence of this high-altitude water vapor plumes is confirmed, it will increase the possibility that missions to Europa would no longer involve drilling through the icy world's thick shell to sample Europa's ocean.
The moon has a large global ocean that contains about twice as much water present in the Earth's ocean, but this is protected by a layer of cold and hard ice whose thickness scientists have not yet determined.
A robotic probe similar to those NASA sent to conduct studies on the surface of Mars may land on the icy surface of Europa to sample the moon's subsurface ocean, which could provide information about the chemicals present in the moon's water or even reveal signs of life.
Water plumes, however, can make the investigation much easier. Instead of having to drill through thick icy shells, a probe can just analyze the chemical content of the plumes.
A similar technique has already been done by NASA elsewhere in the Solar System. The Cassini spacecraft, for instance, sampled the icy plumes spewed by Enceladus, revealing that the subsurface ocean in Saturn's sixth largest moon is salty and has organic molecules.
Just like Saturn's Enceladus, Jupiter's Europa is among the most promising worlds in the Solar System that can potentially host life. If the existence of the plume is confirmed, Europa will also become the second moon in the solar system known to have water vapor plumes.
"Europa's ocean is considered to be one of the most promising places that could potentially harbor life in the solar system," said NASA's Science Mission Directorate acting associate administrator Geoff Yoder. "These plumes, if they do indeed exist, may provide another way to sample Europa's subsurface."
It is estimated that the plumes on Europa rise about 125 miles off the surface before it possibly rains materials back down into the icy surface.