Life most likely appeared on Earth more than 4 billion years ago. In order to understand how it appeared, it is necessary to study the most ancient rocks containing traces of life. Mars, known sometimes as the Red Planet, is the fourth planet of the Solar System. Its topography has similarities with both the Moon, through its craters and impact basins, with the Earth, with formations of origin tectonics and climate such as volcanoes, the valleys, and mesas, fields of dunes and ice caps. The highest mountain in the solar system, Olympus Mons (who is also a shield volcano), and the largest canyon, Valles Marineris, located on Mars.
Petrogenesis of Martian Rocks
Life most likely appeared on Earth more than 4 billion years ago. In order to understand how it appeared, it is necessary to study the most ancient rocks containing traces of life. However, these investigations are hampered by the fact that the earliest traces of life, dating back to the first billion years of Earth's history, are lacking because suitably aged rocks have either been destroyed by plate tectonics or have been severely metamorphosed. The most ancient morphological and chemical traces of life found to date are thus younger than 3.5 billion years (Ga).
In order to go further back into the past, investigations now focus on the search for the oldest traces of life on other planets, in particular on Mars. Indeed, during its first billion years of existence, the conditions on Mars where in many respects similar to those existing on the primitive Earth. In particular, it is now well established that liquid water was relatively abundant during the Noachian (from 4.5 to 3.5 Ga ago). All the conditions required for the occurrence of life were present: liquid water, carbon, essential elements including nutrients and energy. Thus, life may have appeared on Mars and, since there has been no plate tectonic reworking of the Martian crust, well preserved fossil remains of the early microorganisms could be found embedded in sedimentary rocks. The next European mission to Mars in 2016, ESA's ExoMars mission, will be dedicated to the search for traces of life, past or present.
Mars, known as the "red planet" is located at an average distance to the sun 227 900 000 kilometers, its mass is 6.421 x10 23.kg. The composition of the atmosphere has long been a subject of controversy and the possibility of life on this planet, but after the landing of Mars Pathfinder browser has been able to determine the atmospheric composition, which contains: Carbon dioxide (95.32%), Nitrogen (2.7%), and other items with 1.8% complete the composition of the Martian atmosphere. The surface temperature ranges from -140 º C and 20 º C, a day on Mars is equivalent to 1 day 37 minutes 26.4 seconds land on Mars last year Earth 686.98 days (longer than ours), in recent years NASA has launched probes to study the red planet, they have given us a clearer idea of the components of the atmosphere ...