(ORDO NEWS) — In the search for life beyond Earth, underground water bodies in the outer solar system are among the most important targets.
That’s why NASA is sending the Europa Clipper spacecraft to Jupiter’s moon Europa: there’s strong evidence that there’s an ocean underneath the thick crust of ice that could potentially be habitable.
But scientists believe that the ocean is not the only water on Europa.
Based on observations from NASA’s Galileo orbiter, they believe reservoirs of salty liquid could be inside the moon’s icy shell. Some of them are close to the surface of the ice, and some are many kilometers below.
A key discovery in a paper published recently in the journal Planetary Science confirms the long-held idea that water could potentially erupt over Europa’s surface, either as plumes of steam or as a result of cryovolcanic activity.
Computer modeling shows that if Europa has eruptions, they most likely originate from shallow, wide lakes, and not from the ocean.
The simulations give an idea of what scientists might find inside the ice if they were to observe eruptions on the surface.
According to the models, they would see reservoirs relatively close to the surface, in the upper layers of the crust, where the ice is coldest and most fragile.
When water pockets freeze and expand, they can shatter the surrounding ice and cause eruptions, similar to how a soda can explodes in a freezer. And the pockets of water that break through are likely to be wide and flat.
Reservoirs deeper than 8 km will, as they expand, push against the warmer ice surrounding them. This ice is soft enough to absorb pressure rather than burst. Pockets of water will behave like liquid-filled balloons, expanding as the liquid inside freezes and expands.
The Europa Clipper will carry instruments that will test the new theory. Science cameras will be able to take high-resolution color and stereoscopic images of Europa, and a thermal imager will use an infrared camera to map Europa’s temperatures and look for clues to geological activity.
Plume eruptions can be observed using an ultraviolet spectrograph. One of the key tools for finding water pockets in ice is the Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON) radar instrument.
Contact us: [email protected]