Winters on Mars shaping planet’s landscape, explains study

Winter on Mars – which causes carbon dioxide to freeze – alters the appearance of sand dunes, according to a study that explains how land features are formed on the red planet in the absence of large amounts of liquid water. Researchers conducted lab-based experiments on carbon dioxide (CO2) sublimation – the process by which a substance changes from a solid to a gas without an intermediate liquid phase.

The findings suggest the same process is responsible for altering the appearance of sand dunes on Mars. “We have all heard the exciting news snippets about the evidence for water on Mars,” said Lauren Mc Keown, from Trinity College Dublin in the UK. “However, the current Martian climate does not frequently support water in its liquid state – so it is important that we understand the role of other volatiles that are likely modifying Mars today,” said Mc Keown.

“Mars’ atmosphere is composed of over 95 per cent CO2, yet we know little about how it interacts with the surface of the planet,” she said. “Mars has seasons, just like Earth, which means that in winter, a lot of the CO2 in the atmosphere changes state from a gas to a solid and …read more