According to a new study, heavy rainfall is assumed to be the reason of formation of valley networks on Mars that resemble a lot to the arid landscapes on Earth. Scientists believe that there must have been enough water on the planet to feed streams that divide channels into the subsoil. The origin of water on mars has been a matter of debate for several years.
There have been two scenarios i.e. the rainwater caused streams and rivers to swell or ice in the soil melt due to volcanic activity and seep out to form rivers. These two situations are absolutely different and give opposite conclusions about the history of Mars. A study from Science Advances which has all mapped river valleys on Mars that came down on the corner of the contours which are formed by surface run-off of water. There must have been heavy rainfall on Mars over a prolonged period of time which helped in shaping the valley networks. This is the same way valleys develop in arid regions on Earth. Conditions like terrestrial arid landscapes prevailed on Mars for almost 3.6 to 3.8 billion years ago. A hypothesis says that northern third of Mars was covered by ocean at one point of time but later the water evaporated and condensed all around the volcanoes of southern highlands and which led to heavy rainfall. The main question is where is all the water and scientists think that the water has evaporated into space.
By: Swati Kaushal