Exobiologists hunting for non-terrestrial life in the Solar System have a new place to test their theories here on Earth, as geologists have recently found a pair of salty lakes hidden beneath a glacier.
The two newly discovered lakes were found beneath the Canadian High Arctic using radar, and a similar technique will soon be used by NASA‘s Europa Clipper to observe and study the subsurface ocean of the Jovian moon, Europa.
Astronomers are keen to understand Europa’s ocean as it is thought to be our best chance of finding non-terrestrial life within our Solar System.
The Canadian lakes are similar to Europa’s ocean in several key ways.
Unlike the previous 400 underground lakes that have been discovered on Earth, these lakes are extremely salty.
Europa’s ocean is thought to have a similar salinity, which prevents the water from freezing solid.
The Canadian lakes are buried under 550 to 750 meters of ice, and so have been cut off from both the Sun and global atmosphere for thousands of years.
“If there is microbial life in these lakes, it has likely been under the ice for at least 120,000 years, so it evolved in isolation,” says Anja Rutishauser, from the University of Alberta who led the study.
This unusual set of conditions means that the Canadian subsurface lakes are a great analogy for the potential conditions that growing life would have to endure on Europa.
“If we can collect a sample of the water [from the Canadian lakes], we may determine whether microbial life exists, how it evolved, and how it continues to live in this cold environment with no connection to the atmosphere,” says Rutishauser.
The depth of the lakes also means that planetary geologists will be able to test run the kinds of techniques that the Europa Clipper will use to look at the icy moon, ensuring the mission gets the most out of its trip to the moon when it arrives in the late 2020s.