We are a curious look, seduced by the unknown, and enchanted by strange travels of exploration into the most secretive and shady corners of the universe. Secrets sing a siren song to us, seduce us and fascinate us with any miracles that may lie behind the horizon of our knowledge. The possibility of life on the worlds outside of our Earth has always pursued the dreams of those who dare to dream, and the little red world Mars paid special attention to us as the most likely "close" abode of life, which is unearthly. Mars is a cold world with a sky painted in debris - a planet that showed a lot of geographical evidence that rivers of cheerful liquid water periodically flowed over a reddish surface. In January 2017, scientists at Harvard University announced that this world — cold from Earthlings & standards — may have once been warm enough to allow these flowing rivers of liquid water to exist as a result of intermittent and powerful Greenhouse effect caused by bursts of methane.
An apprentice's existence of liquid water on Mars is puzzling. For a period of time, the rivers were to wander across the surface of the Red Planet - about three or four billion years ago - Mars must were too cold to keep water in its liquid phase.
How did Mars manage to warm up so warmly?
In an article published in Geophysical Research Letters scientists from Harvard John A. Paulson School of Engineering and Applied Science (SEAS) in Cambridge, Massachusetts, it has now been suggested that ancient dances between methane, carbon dioxide and hydrogen in the early Martian atmosphere might be responsible for these mysteriously mild periods. This interaction could create warm episodes that allowed Mars to maintain liquid water on its surface.
“Early Mars is unique in the sense that it is one planetary environment outside the Earth, where we can say with confidence that there were at least episodic periods when life could flourish. On the potential to find life on other planets outside the solar system ", Dr. Robin Wordsworth explained January 24, 2017 Press release SEAS. Dr. Wordsworth - Associate Professor of Ecology and SEAS , and the first author of the research work.
Strange warm world
Mars rotates our Sun in a reliably warm and well-lit interior of our solar system, where our Star is bright enough to blast its alien sky with its fabulous light and amazing distant lights. Mars is the fourth planet of our Sun, and the second is the smallest planet in our solar family of eight major planets. The smallest large planet in our solar system is Mercury, covered with the sun, the innermost world of our solar system.
Mars was named after the Roman god of war because of its rusty surface - so it is often called the “Red Planet”. This rusty red color is caused by iron oxide, which is very abundant in the Martian landscape. earthly planet the subtle atmosphere, the features that characterize the surface of Mars, pursue similarities with the polar ice caps, valleys and deserts of our Earth - as well as scattered scars created by impact craters that hit our own planet. big moon. The Martian seasons, as well as the period of its rotation, are also similar to the times of the Earth.
Unlike the reliably large Moon of the Earth, Mars revolves around the pitiful, though interesting, duet of tiny irregular moons. This deformed duet, called Phobos and Deimos are generally considered born as asteroids that inhabit Main asteroid belt which is located between Mars and our Solar System - the giant-giant giant, Jupiter. According to this scenario, two small deformed asteroids wandered from their place of birth into the space between the planets - only to be caught and extremely captured by the powerful gravity of the Red Planet, that they are now in orbit.
Mars is a mysterious, fascinating world that has become the object of much of the current scientific research, seeking clues about wherever the ancient life is perhaps once existed there - as well as intriguing chance that Mars can still take some protracted tidbits of life. Because of this fascinating opportunity, Mars became the object of a number of planned astrobiological missions, including Mars 2020 and ExoMars rover
The existence of liquid water is necessary for life, because we know it in order to develop and flourish on worlds other than our Earth. Due to the low atmospheric pressure on Mars, the presence of liquid water on its surface is small - limited to areas with low altitude, and here only for very short periods of time. Two Martian polar ice caps, apparently, consist mainly of water. The amount of water ice on the south polar Martian ice cap, if it were to warm up and melt, would be sufficient to cover the entire surface of Mars to a depth of 36 feet. On November 22, 2016, NASA announced the discovery of significant amounts of subsurface ice in Utopia planitia region of the Red Planet. The amount of water found is estimated to be approximately equal to the volume of water in Lake Superior.
Back in the 1970s, planetary scientists discovered canals and valleys on Mars, which, in their opinion, could have been cut and destroyed by rain and surface runoff - just like on our own planet. In August 2016, widespread systems of petrified river beds were discovered in the ancient region of the Martian surface, therefore adding confidence to the theory that the cold and arid world was once a warm, warm, humid climate about four billion years ago. This observation was made by a group of planetary scientists headed by researchers at the faculty of University College London (UCL) in England.
An article describing this study published in the journal geology and funded Science and Technology Council and British Space Agency, identified over 17,000 kilometers of ancient former river canals on the northern plain Arabia Terra. This discovery reinforced the theory that liquid water once flowed on the surface of Mars.
"Climate models of early Mars predict rain in Arabia terra and so far there has been little geological evidence on the surface to support this theory. sheets and glaciers. We have now found evidence of extensive river systems in the area that support the idea that Mars was warm and humid, providing a more favorable living environment than a cold, dry planet, ”explained study lead author Dr. Joel Davis. August 24, 2016 UCL press release. Dr. Davis works in the Department of Earth Sciences at UCL.
The study looked at images covering a region roughly equal to Brazil, with a significantly higher resolution than was possible in previous observations. While several valleys were discovered, the team discovered the existence of numerous fossil riverbed systems. These ancient river beds can be viewed as inverted canals, which Arabia terra plain.
Inverted channels are similar to those observed elsewhere on Mars and on Earth. They consist of gravel and sand, which were besieged by the river. When the river broke down, the canals remained to tell an ancient story. Channels now look like great features as the surrounding material collapses. On our own planet, inverted canals often form in dry, desert areas such as Oman, Egypt or Utah, where erosion rates are sluggish. In most other environments, the channels wear out long before they can be turned over.
"Networks of inverted channels in Arabia terra They are about 10 m high and up to 1-2 km wide, so we believe that they are probably the remains of giant rivers that flow billions of years ago. highlands and lowlands of Mars. We believe that the rivers were active 3.9–3.7 billion years ago, but gradually discharged before they were quickly buried and protected billions of years, potentially supporting any ancient biological material that could be present, ”said Dr. Davis on August 24, 2016 UCL press release.
“These ancient Martian floodplaces would have great places to search to find evidence of past life. In fact, one of these inverted channels was called Aram dorsum is the candidate's landing site for European Space Agency ExoMars Rover The mission, which will start in 2020, was commented by Dr. Matthew Balm in the same UCL press release Dr. Balme is a senior lecturer at an open university in the UK and co-authored the study.
Ancient Mars, heated by bursts of methane
Four billion years ago, our Star was 30 percent weaker than it is now. In addition, much less solar radiation (heat) was able to break through to the surface of ancient Mars. A small amount of radiation, which managed to tire the road to the Red Planet, was captured by the atmosphere of Mars. This was allowed for a time that was warm and humid. For decades, scientists have tried to develop a model that explains exactly how Mars was isolated.
The corresponding cause is carbon dioxide. Carbon dioxide makes up about 95 percent of the current atmosphere of Mars, and it is the most famous and most abundant greenhouse gas on Earth.
But only carbon dioxide can not explain to Mars. early warm temperatures.
“You can do climate calculations when you add carbon dioxide and accumulate atmospheric pressure on Mars up to hundreds of times, and you still never get temperatures close to the melting point,” said Dr. Wordsworth in January 24, 2017 SEAS press release ,
Since carbon dioxide alone cannot cope with the temperature of the ancient red planet, the missing ingredient must be present in the atmosphere of Mars, which also contributed to the greenhouse effect.
rocky (earthly) planets , such as our Earth and Mars, cannot maintain a good gravitational grip on their lighter gases, such as hydrogen. Sometimes these light gases are lost in the interplanetary space. Indeed, the oxidation, which explains the rusty red tint of the surface of Mars, is a direct result of the loss of hydrogen.
Dr. Wordsworth and his team studied these long-lost light gases. (reducing gases) to shed light on a possible explanation for Mars. pristine climate. The team of scientists was especially interested in methane, which is currently not abundant in the thin Martian atmosphere. However, billions of years ago, some geological processes could send significantly more methane into the atmosphere of Mars. This methane may have gradually experienced a sea change in hydrogen and other gases, as a result of a process that is similar to what is currently happening on smogan, tormenting, mutant of the moon, Titan.
To understand how this ancient Martian atmosphere could behave, scientists needed to understand the basic properties of these molecules.
“When you look at exotic atmospheres, you cannot compare them with the atmosphere of the Earth. You must start from the first principles. Therefore, we looked at what happens when methane, hydrogen and carbon dioxide collide, and how they interact with photons. found that this combination leads to a very strong absorption of radiation, ”says Dr. Wordsworth explained on January 24, 2017 Press release SEAS.
Back in 1977, the late Dr. Carl Sagan, an astronomer at Cornell University in Ithaca, New York, first suggested that hydrogen warming could be an important factor affecting ancient Mars. but SEAS a study for the first time shows that scientists were able to accurately calculate their greenhouse effect. It was also the first time that methane was shown to be an effective greenhouse gas on ancient Mars.
"This study shows that the warm effects of both methane and hydrogen were underestimated by a significant amount." We found that methane and hydrogen and their interaction with carbon dioxide were much better when heated early Mars than previously thought, ”continues Dr. Wordsworth in Press release SEAS.
Scientists hope that future missions to Mars will show the nature of the geological processes that spawned billions of methane years ago.
Dr. Wordsworth added that “One of the reasons for early Mars is so fascinating that life requires complex chemistry. These episodes of reducing emissions of gases, accompanied by planetary oxidation, could create favorable conditions for life on Mars. "
