The Dhaka Times Desk Once again, scientists have presented more evidence of the presence of water on Mars. 3.5 billion year old river channels have been traced across the Martian surface. This suggests that the planet could have once held a stream of liquid water.
Scientists claim that the densest and most extensive accumulation of river sediments has also been seen in a region called Aeolis Dorsa on Mars.
It is known that satellite images of the course of these ancient rivers are mainly due to a special geological phenomenon. In this phenomenon called topographic inversion, sedimentation of ancient shallow rivers gives them the appearance of deep trenches.
Jackson School of Geoscience researcher B. T. Cárdenas and his colleagues claim to be able to identify sedimentary layers near the seabed by combining high-resolution images and geospatial data collected by high-resolution cameras on satellites. Through this they have also been able to observe the record of the course of the river changing at different times.
Combining the two types of observations suggests that layers of fluvial sediment filled the once incised valleys. On Earth, such valleys are eroded and filled again as sea level rises.
Cárdenas and his co-researchers made similar observations on the surface of Mars. They have found that similar signs of sea level rise and fall have been observed on Earth, as well as similar signs have been found on Mars by observing the formation of valleys, the researchers claimed. From these data, researchers understand that there were once flowing water streams and seas on Mars.
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