Salt from the subterranean sea on Jupiter’s satellite to Europe can leak to the surface. As shown by the new study, the detected darkening may be due to radiation. "It would be a simple and elegant explanation of what this dark material is," said planetary scientist Kevin Hand, from NASA's Jet Propulsion Laboratory in Pasadena, California, in a press release.
Scientists tried to find out the source and composition of dark material located along cracks and other relatively young geological features in Europe. Complicating the picture is the harsh radiation situation in Europe, which has been pierced by particles around Jupiter’s powerful magnetic field.
In a report that was published in the journal Geophysical Research Letters, Hand and co-author Robert Carlson described laboratory tests in which they try to match the colors of various irradiated substances with the spectrum of colors found by Galileo’s spacecraft and several telescopes in cracks in Europe . In addition to previous studies showing that sulfur and magnesium are potential sources of ignition, the new experiment shows that good old table salt, sodium chloride, is also a suitable material.
Scientists have tested the salt, as well as a mixture of salt and water in a vacuum chamber set at minus 280 degrees Fahrenheit. They then used an electron beam to blow up materials, simulating the radiation situation in Europe.
White salt turned yellow-brown, a color similar to the one that was found inside the faults on the surface of the satellite.
"The chemical traces of radiation-baked sodium chloride turned out to be very interesting information for detecting mysterious material in Europe," said Hand.
Scientists are trying to put together enough information to find out if there are conditions on Europe that are suitable for life.
