Newly discovered glass dunes on Mars indicate water on the red planet, according to a recent study. The dunes spread across almost a third of the planet are most likely the result of volcanic explosions coming into contact with water - suggestive of an environment that could sustain life.
Researchers found the glass dunes of tiny glass particles from a reanalysis of images sent back to Earth from the European Space Agency's Mars Express orbiter. The Martian glass dessert is similar to the one that takes up thousands of square miles in Iceland and was created by volcanic activity, researchers said.
The only way to create an extensive glassy deposit like that is through explosive volcanism, Briony Horgan, study coauthor and postdoctoral research fellow at Arizona State University, said in a statement. This is the first direct evidence on Mars for explosive volcanism on a planetary scale.
Rapidly cooling lava in ice or water prevents crystal formation and creates volcanic glass, according to the study.
The volcanic glass was created when hot magma reacted explosively with ice or water, Horgan told Discovery News. The same sort of thing happens in Iceland, where volcanoes erupt under glaciers. These form vast sand dunes covering about a quarter of Iceland's surface, which is exactly what we're seeing on Mars.
Researchers also uncovered evidence of weathering consistent with the glass being exposed to acidic water, created when water or ice mixes with the glass sand. If the water were not being constantly replenished, the acidic water would eventually neutralize and stop eroding the dunes, according to the study authors.
The glass indicates that water may exist beneath the surface, researchers said. Glass dunes are not probable locations for extraterrestrial life, subsurface water could provide nutrients microscopic organisms need to survive, the study authors said.
It's the perfect place for microbes, Horgan said in a statement. A nice, warm, safe place for microbes to hang out with lots of chemicals around to munch on.
If the glass sand were created in the same manner as it was on Earth, it definitely bodes well for potential life, Claire Cousins, astrobiology researcher at the University College London, who was not involved in the study, said in a statement. Cousins studies volcanic environments in Iceland as Martian analogues.
Regions of volcano-ice interactions on Earth provide a wide range of hydrothermal environments that can be exploited by microbial life, she said.
The researchers said their next step is to study other images and come up with a concrete suggestion for where to look for life.
It's something we're really excited to look into, they said.
The journal Geology published the study in its April edition.