In the warm, well-lit areas of our solar system, four rocky terrestrial planets - Mercury, Venus, Earth and Mars - bask in the fierce golden fires and the intense heat of our Star, the Sun. This quartet of relatively small worlds mainly consists of silicate rocks and metals - and they all have hard surfaces, unlike the four giant gaseous inhabitants of the cold outer areas of our Solar System - Jupiter, Saturn, Uranus and Neptune - which consist of various mixtures of hydrogen, helium and water existing in different physical states. But sometimes no other planet in our Sun family attracted our attention — and our imaginations tickled — more than Mars, the fourth planet from our Sun, as well as the closest neighbor of the Earth in space. This is because we recognize it as a home planet outside of our own Earth, which is likely to take life as we know it. However, in December 2015, two French scientists weakened this particular perspective when they published their data indicating that Martian ravines may have been formed due to dry ice processes, and not because of life-supporting fluid, as it was believed earlier.
This study was published online in a December 21, 2015 issue. Nature Geoscience. Two French astronomers show that, at the end of winter and spring, the benefits of a seasonal ice layer on carbon (CO2) warmed by our star, intense gas flows can destabilize the regolith material and trigger gaseous trash flows that look deceptively like water sculptural ravines on Earth .
Since 2000, cameras in orbit around Mars have sent to Earth a treasury of images of small valleys carved on slopes similar in shape to the ravines created by streams of flowing water on our own planet. It seems that the ravines less than a few million years is not a very long time on a geological time scale. Indeed, some of the ravines even seem less than just a few years old! This discovery was suggested to the planet scientists that today a large amount of liquid water may remain on Mars and that this water may be responsible for cutting the ravines.
Recently, this particular model has been questioned as a result of frequent observations of the surface of Mars. Hirize camera on board NASA Mars Orbiter (MRO) These new observations show that the formation of ravines continues on Mars, at a time when the surface environment of this planet is too cold for liquid water. However, the observed activity of the ravines, apparently, occurs when the CO2-ice, which condenses out of the atmosphere of Mars during the winter, melts on the surface of this planet. Can two phenomena be related? That is the question. If so, how did the thin seasonal layer of dry ice deposited over the regolith cause the formation of 10 mm fragments of debris that behaved and looked as if they were caused by a liquid?
Kingdom Rocky "Red Planet"
Mars is often called the “Red Planet” because of the abundant iron oxide on its surface, which gives it a red hue. This rocky, Earth-like planet is covered only by a very thin atmosphere, and it shows surface features that intrusively resemble impact craters that get stuck in Earth, as well as deserts, volcanoes, valleys and polar ice, the caps of our planet. The rotation period as well as the Martian seasons are also similar to the periods of the Earth, as well as the inclination that causes seasonal cycles. The Martian surface also shows the largest volcano and the second highest mountain (Olymp Mons) in our solar system as well Valles marineris which is one of our largest canyons of the solar system. Smooth Borealis Pool , which covers 40% of the surface of Mars, is located in the northern hemisphere, and it is believed that it was a huge scar left a destructive body for a long time.
Mars also has two small moons called Phobos and Deimos The small deformed moons are probably captured by asteroids occurring in Main asteroid belt between Mars and Jupiter, who wandered far away from home, only to be embraced by the gravitational pull of the planet, that they are now in orbit. Both tiny moons are interesting little potato bodies, but they lack the bright, brilliant and haunting charm of a large lunar satellite of Earth.
terrestrial - named houses telluric - Planet, Mars shares some important characteristics with three other rocky inner planets, including our own. All four terrestrial The planets have the same structure: the central metallic core, which mainly consists of iron enclosed in a silicate mantle. In addition, the four rocky inner planets of our Sun may have secondary atmospheres that developed as a result of volcanic eruptions or comet strikes, or both. In dramatic contrast, the quartet of gas giants who inhabit the outer edges of the solar system are all sporting primary atmospheres. Planetary scientists, as a rule, believe that the four outer planets, which live far from the golden, melting heat of the Sun, capture their extremely heavy gaseous atmospheres directly from the original protoplanetary accretion disk circling our newborn star.
Astronomers have discovered a large number of similar protoplanetary accretion disks circling around young, distant stars outside of our sun. These discs form at about the same time as their parent stars, in an opaque curtain that covers the natal drop consisting of gas and dust. protoplanetary accretion disk nourishes a starving newborn star with a rich formula of gas and dust, so that the baby star can ever grow to achieve true brilliant glory. Accretion discs can spin around their childhood stars over 10 million years.
Mariner 4 He achieved the first successful flight of the Red Planet half a century ago, in 1965. This early visit contributed to a lot of speculation among members of the astronomical community, and some scientists then justified the existence of a life-supporting pool of liquid water on the Martian surface. This theory was based on the observed periodic changes in dark and light areas, especially in the polar territories on Mars, which resembled seas and continents — long dark blows that some planet researchers interpreted as irrigation canals for pouring liquid water. However, these mysterious lines were in the final the result is defined as simply optical illusions. Nevertheless, the geological data continued to sing a charming siren song, which Mars had once covered with plenty of liquid water. Indeed, in 2005, radar data showed that a large amount of water ice escaped at the Martian poles, as well as in middle latitudes. Mars rover Spirit detected chemical compounds containing water molecules in March 2007, and Phoenix the planting site is directly spotted water ice in shallow soil samples on July 31, 2008.
Currently, Mars is visited by seven spacecraft whose quintet is in orbit: 2001 Mars Odyssey, Mars Express, Mars exploration orbiter, MAVEN, and Mission Mars Orbit. A duo of missions that are currently moving on the surface of Mars, Rover Rover Mars features and Mars Science Laboratory (MSL).
At present, there is a conflict between the predictions of the ancient climate of Mars, derived from models developed by paleoclimatologists, and various proposals that the planet had a very strong past, as was suggested by geologists.
Dry ice Sculptures on Mars?
In order to better understand the mysterious interaction between carbon frost and surface materials on Mars, two French scientists, Dr. Cedric Piloretg, researcher French National Center for Scientific Research (CNRS / Universite Paris-Sud) and Dr. Francois Forget about UPMC / ENS Paris / CNRS / Ecole polytechnique, developed a numerical model that they used to simulate the environment on a slope. From the subsurface regolith to the atmosphere looming above, the model takes into account changes in energy resulting from radiation, thermal conductivity, or induced by changes in the CO2 phase.
One very important character of the places where CO2-ice is found is that on the surface of Mars there is always a layer of permafrost consisting of water-ice particles, only a few centimeters. Therefore, when CO2 condenses on the surface in winter, the air present in the porous subsurface is imputed between the impermeable permafrost layer below and the ice layer CO2 above.
Under such conditions, numerical simulations developed by Dr. Piloteg and Dr. Forget missed some intriguing surprises. At the end of winter or spring, the light from our sun cuts straight into the layer of translucent CO2 ice and worms from below. The CO2 layer does not melt as a result of this heat, but instead goes directly into the vapor state. ( sublimated). The gas then spreads through the porous near-surface soil, and only a small percentage can condense there again, while most of the remaining gas is collected in the porous region. This can significantly increase the surface pressure, several times higher than the value of atmospheric pressure. The ice layer of CO2 finally breaks down, causing a strong decompression. Within a few seconds — and up to a few minutes — several cubic meters of gas (as well as several dozen cubic meters around the vent holes) should then be pushed through the soil surface. Such forced flows can destabilize granular soils with the formation of granular flows. In addition, they are also able to revive an avalanche, which can act as a viscous fluid.
This process has no exact analogue on our planet. However, it can be compared with the pyroclastic flows of the Earth. These streams consist of gas-air mixtures that are produced during fiery volcanic eruptions, and they can travel for several kilometers even on extremely moderate slopes. In addition, they can also carry stones the size of meters, and, as was seen, they show side “dams” that are about the same size as those visible on the side of the Martian ravines. As on our own planet, where debris resulting from rain or melting snow are unusual phenomena, it is highly likely that a rare combination of circumstances is required to destabilize the Martian slopes.
The model developed by two French planetary scientists can also explain why the Martian ravines are located mainly in the latitude range of 30 degrees 60 degrees - with several areas at higher latitudes - and also why most ravines are observed on slopes from 30 degrees to 45 degrees It was predicted that emissions and fluidization caused by CO2 occur exactly where the ravines are visible.
All these data show that the heat of the Sun melting seasonal dry ice deposited in winter on the slopes of the Red Planet is the source of the proportion (or perhaps even all) of the observed ravines. This process has no terrestrial analogs and does not require the existence of viable liquid water. According to this study, ravines on Mars may not have provided a living environment in the past.
