The conventional scientific method is like this, in order to explain any event under consideration, the phenomena must be subjected to experiments and continuous observations. The theories are superseded by new findings. There has been some great news coming for all the Astro freaks recently. A new theory for valley formation in the Martian surface was put forward by Anna Grau Galofre, A. Mark Jellinek & Gordon R. Osinski in the journal of Nature Geoscience. This thesis could be a milestone in the study of the ‘habitable mars concept’.
Mars is the fourth planet in terms of its position from the Sun. It is slightly larger than Mercury and is seen in red colour. Using satellites, about ten thousand different traces of valleys in the Martian surface has been spotted. Till now these valleys are believed to form due to erosive process by wind or river water on the surface. This ‘wet and warm mars‘ concept is superseded by the new pieces of information provided by the team of researchers. According to them, the water melting beneath glaciers which were present billions of years ago on the surface is responsible for these patterns.
In the Earth, there are many patterns of erosions that are extremely different from each other based on the formation scenarios like rainfall, river flow,etc and they can be used as tools for understanding the surface of the red planet. According to the Co-author Gordon Osinski, Professor in Western University’s department of earth sciences and Institute for Earth and Space Exploration, Devon island in Canadian Artics is the best analogues on Earth to study Mars. It is a cold dry polar region similar to the desert and this region resembles the surface of Mars. Scientists had observed this region for their inferences.
Martian valleys were observed 40 years ago and the observations from then, were used to create detailed maps of the Martian surface. The Mars Orbiter Laser Altimeter (MOLA), which flew on NASA’s Mars Global Surveyor spacecraft was used to study the Red Planet between 1997 and 2001. A novel program had been developed by the team, which incorporated six different characteristics of more than 10,000 valley segments, and they compared each cluster with four different scenarios of formation of valleys on the earth’s surface. About one-third of observations matched the newly put forward theory of subglacial erosion and a handful of observations similar to erosion made by rivers and some were not distinct enough to make any statements.
The lead author Anna Grau Galofr [former Ph.D. student in UBC’s Department of Earth Ocean and Atmospheric Sciences], currently at School of Earth and Space Exploration (SESE) Postdoctoral Fellow at Arizona State University, had developed and used new techniques to examine thousands of Martian valleys. Her theory also throws light on the way these valleys would have formed 3.8 billion years ago on a distant planet during the time when the sun was less intense and hot. According to her, all the valleys observed were distinct, which lead to the conclusion that several mechanisms had shaped these patterns.
These suggested environments would also support viable conditions for possible ancient life on Mars. Ice caps and sheet-like layering could give more protection and stability to underlying water, they could also stand as a shield from solar radiation in the absence of a magnetic field—something Mars once had, but disappeared billions of years ago. Let’s all wait and see the impacts of this theory in moulding new views about Mars…
Journal Reference: Valley formation on early Mars by subglacial and fluvial erosion,
Nature Geoscience (2020). DOI: 10.1038/s41561-020-0618-x
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