(CN) – Researchers made a startling discovery challenging scientific consensus regarding the composition of the subterranean oceans on Europa, one of 79 moons orbiting Jupiter.
The Hubble Space Telescope detected the likely presence of sodium chloride – table salt – on Europa, indicating the subsurface seas of the moon may be similar to those of Earth.
“Magnesium sulfate would simply have leached into the ocean from rocks on the ocean floor, but sodium chloride may indicate the ocean floor is hydrothermally active,” said Samantha Trumbo, lead author of a study published Wednesday in Science Advances. “That would mean Europa is a more geologically interesting planetary body than previously believed.”
Previously, scientists believed Europa’s subsurface seas were comprised of magnesium sulfate salts, resembling epsom salts, based on photographic evidence provided by NASA flybys conducted by Voyager and Galileo spacecraft.
Table salt is translucent and would not be visible, accounting for why scientists did not believe the yellow material accumulated on the moon was table salt.
But recently Kevin Hand with the Jet Propulsion Laboratory blasted table salt with bursts of radiation to simulate the conditions on Europa. The samples turned a shade of yellow similar to that found in certain regions of the moon.
“Sodium chloride is a bit like invisible ink on Europa’s surface,” Hand said. “Before irradiation you can’t tell it’s there, but after irradiation the color jumps right out at you.”
Trumbo and her co-authors acknowledge the presence of table salt on the surface of Europa doesn’t necessarily mean it derived from the ocean below, they believe it should force a reconsideration of the geological composition of the moon – particularly as the concentrations of the salt are distributed around sections of the surface where ice is drifting apart.
The development is particularly important as there are increasing calls for NASA to explore Europa due to the potential habitability of the moon.
The presence of water means certain types of bacteria, algae and other organisms could flourish in the ocean, making Europa one of the few planetary objects in the solar system capable of supporting carbon-based life forms.
NASA has revealed plans to send the Europa Clipper at some point in the early 2020s to take measurements of the various geological features on the moon.
Europa is one of the four so-called Galilean moons, first spotted by Galileo Galilei in 1609 – the first objects in the solar system outside our own moon discovered orbiting another planet. Europa is the smallest of the four.