Mars's icy dunes hint at clues of past life possibilities
While the beans in the photo might resemble beans, the probe actually captured images of large frozen dunes on Mars. NASA has just unveiled this discovery, which scientists suggest could indicate that life may have once existed there.
The Mars Reconnaissance Orbiter (MRO) photographed the Martian dunes in the northern hemisphere of the Red Planet from above. The image presents a view taken by the High-Resolution Imaging Science Experiment (HiRISE) camera during a flight over these icy formations. This offers researchers the chance to ascertain whether life might have previously existed on Mars.
Martian dunes are frosted, but their ice is not water-based
NASA shared this remarkable finding, although the photo was captured earlier, in September 2022. Scientists have established that, although the frost on the dunes is composed of carbon dioxide rather than water, it still influences the possibility that water existed on Mars for an extended period in the past, according to NASA. This discovery provides new hope for detecting past or existing forms of life. The photographs of the frost-covered dunes aid scientists determine whether water ever persisted on the planet's surface long enough for life to emerge and endure on Mars.
Why is there CO2 ice on Mars? The amount of carbon dioxide on the Red Planet is linked to its tilt towards the Sun. When Mars tilts sufficiently, carbon dioxide ice sublimates into gas on a large scale, leading to a thicker atmosphere for the entire planet. This denser atmosphere might have sufficed to preserve liquid water for a prolonged period. Gaining a better understanding of how carbon dioxide frost forms and dissipates under current conditions on Mars enables scientists to make more accurate predictions about Mars's past climate. If conditions once favoured stable liquid water, Mars could probably have sustained microbial life—and perhaps such life still lingers somewhere.
The dunes in the image are coated with a layer of carbon dioxide frost, but only during the winter in Mars's northern hemisphere. Interestingly, Martian dunes move like their Earthly counterparts: the wind blows sand, accumulating it elsewhere. Martian sand primarily comprises basalt, a material formed from crushed volcanic rock. According to NASA, recent studies indicate that winter frost halts the movement of sand grains, immobilising the dunes until the spring thaw. This discovery offers insights into historical Martian conditions and the potential for life.
Ice frost halts the movement of wandering Martian dunes
By scrutinising the dunes on Mars and the behaviour of carbon dioxide frost under present conditions, scientists can better estimate the Red Planet's historical climate. Investigating how frost varies with the seasons also helps researchers identify geological formations influenced by carbon dioxide, uncovering further details about the planet's evolving climate. If there have been eras favouring stable liquid water, the likelihood that Mars could have supported microbial life is high—and it might still be lurking somewhere.
