For years now, the scientific world believed that in ancient times Mars was able to host life. As water is a mineral that is vital for any form of life, astronomers are looking for any signs of liquid water on planets. NASA Curiosity rover is a robot of the size of a car that has successfully landed on Mars on August 6, 2012. The smart rover has just sent over to Earth a new series of data that can disclose interesting facts about the ancient atmosphere on Mars.
Life on Mars is for the time inexistent. However, the same truth doesn’t apply to its ancient periods of time. The studies of the planet revealed many signs according to which there used to be lots of water sources such as lakes, ponds, rivers, streams, and even oceans. Other thick lines are hinting at some possibilities that there may be streams of liquid water every spring.
One of the most visible formations on Mars is the Gale Crater located on the northwestern side of the Aeolis quadrangle. Scientists estimate it to be around 3.8 billion years old. During its ancient times, the crater has probably hosted an environment favorable to life. Its water must have had the perfect temperature and constitution. To answer this possibility, the planet must have had a warmer ancient atmosphere than it has today. This means that there were large amounts of greenhouses gases that contained high temperatures within the planet.
Thanks to the Curiosity rover, scientists managed to study Martian samples of sandstones, siltstones, mudstones, and other deposited rocks that signal the rivers that existed in the Gale Crater approximately 3.5 billion years ago. However, scientists discovered that the greenhouse gases theory might not be real. There were not enough signs of carbon dioxides, which are a type of greenhouse gases. In their absence, it was not possible for the Red planet to become warm enough to have liquid water.
Nonetheless, other irrefutable marks of the presence of water persuaded scientists not to give up on their research. One possible explanation is that the carbonates were destroyed by natural calamities. However, the collected samples show no sign of a complex chemical reaction. Another explanation might be that the greenhouse gases made their presence felt not through carbon dioxides, but through other chemicals like sulfur dioxides, nitrous dioxides or methane. A third theory regards a change of planetary orbit. Scientists have to conduct more studies to understand how Mars could sustain liquid water on its surface and what kind of life forms it hosted.
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