published 04/20/2022 06:00 / updated 04/20/2022 08:13
(credit: NASA / JPL-Caltech / SETI Institute / Disclosure)
Jupiter’s satellite Europa is a prime candidate for extraterrestrial life in our solar system, and its deep saltwater ocean has fascinated scientists for decades. But this complex is enclosed by a “shell” of ice, which can be kilometers to tens of kilometers thick, making sampling of the material difficult. Now mounting evidence reveals that the frozen surface may be a less complex barrier and site of potential habitability in its own right.
Europe is one of the best places to look for alien life because scientists have detected signs of oxygen and water, as well as substances that can act as nutrients. However, the moon’s ice sheet – estimated to be about 24 km thick – acts as a barrier between the liquid and the chemical element, which is generated by the interaction of sunlight with charged particles hitting the ice surface.
Now, a team led by the University of Texas (UT) at Austin says the salt water inside Europa’s frozen shell could carry oxygen into a liquid ocean where alien life would be possible. The theory has been proposed by other scientists, but researchers have only recently put it to the test by building the first computer simulation of the process, in which oxygen travels on the backs of Jupiter’s moon’s “chaos grounds”. landscapes composed of cracks, ridges and frozen blocks.
The results show that not only is transport possible, but that the amount of oxygen transported into Europa’s ocean could be on a par with that found in Earth’s oceans today. “Our research puts this process in the realm of the possible,” said lead researcher Marc Hesse, a professor in the UT Department of Geological Sciences. “The model provides a solution to what is considered to be one of the outstanding habitability problems of Europa’s subterranean ocean.” The study was published in the journal Geophysical Research Letters.
If life as we know it exists in this ocean, there must be a way for oxygen to get there. According to Hesse, the most plausible scenario, based on the available evidence, is that oxygen is carried by salt water or brine. Scientists believe chaotic terrain forms over regions where Europa’s ice sheet partially melts to form brine, which can mix with surface oxygen. The computational model created has shown that this is possible.
According to co-author Steven Vance, a researcher at the US Space Agency’s Jet Propulsion Laboratory, the result of the work gives hope for the potential of oxygen to support life in the hidden sea of Jupiter’s satellite. “It’s tempting to think of some kind of aerobic organism that lives just under the ice,” he said. According to Vence, NASA’s upcoming Europa Clipper mission, scheduled for 2024, could help improve estimates of the presence of this chemical and other ingredients for life on the icy moon.