The planet Mars has a very thin atmosphere, formed mainly by carbon dioxide, which freezes alternately in each of the poles. It contains only 0.03% water, a thousand times less than Earth.
Studies show that Mars had a more compact atmosphere, with clouds and precipitations that formed rivers. On the surface you can see grooves, islands and coasts.
Large differences in temperature cause very strong winds. In addition, soil erosion helps form dust and sand storms that further degrade the planet's surface.
Before space exploration, it was thought that there could be life on Mars. The observations have not been able to show if he has it, although he could have had it in the past.
Under present conditions, Mars is sterile, can not have life. Its soil is dry and oxidizing, and receives too many ultraviolet rays from the sun.
When it is closer to Earth, at about 55 million kilometers, Mars is, after Venus, the brightest object in the night sky. It can be observed more easily when the straight line Sun-Earth-Mars (that is, when it is in opposition) is formed and is close to Earth, which happens once every 15 years.
The reddish tone of its surface is due to oxidation or corrosion. The dark zones are formed by rocks similar to terrestrial basalt, whose surface has been eroded and oxidized. The brighter regions appear to be composed of similar material, but contain finer particles, such as dust.
Because of the inclination of its axis and the eccentricity of its orbit, Martian summers are short and hot, while winters are long and cold. Huge shiny caps, apparently formed by frost or ice, mark the polar regions of the planet.
The seasonal cycle of Mars has been followed for almost two centuries. In the Martian autumn bright clouds form on the corresponding pole. A thin layer of carbon dioxide is deposited on the polar cap during autumn and winter, at the end of which the polar cap can descend to latitudes of 45 °. In the spring and at the end of the long polar night, the seasonal part falls apart and shows the ice cap of winter, which is permanent.
In the past the atmosphere of our neighbor Mars was much more dense, and had a hot and humid climate, say NASA researchers.
The data, obtained by the Curiosity explorer, allowed NASA specialists to discover that in the atmosphere of Mars, which is now much thinner than terrestrial and consists mainly of carbon dioxide, the proportion of heavy isotopes is much higher .
Light isotopes leave the atmosphere more easily than heavy isotopes, so the Martian atmosphere was 'ripped off' from the planet, the researchers point out. Most likely, a catastrophe of unknown origin occurred that could have been caused by a collision with an object the size of Pluto, or multiple collisions with asteroids.
Most of the atmosphere was destroyed some 3.7 billion years ago, after which it continued to evaporate, scientists believe.
It remains to be determined with more precision when the catastrophe happened and if there was time for life to appear in the favorable environment for it. "It is possible that the densest atmosphere would have kept some parts of the planet warm enough for the microbial life to live," said Paul Mahaffy, of NASA and one of the main authors of the studies.
Previous measurements of telescopes and satellites had reported small amounts of methane in the Martian atmosphere, the engineers of the rover expected to find up to 10 parts per billion or more of this gas, but the reality has been quite a surprise.
From a few days after landing in Cabo Gale, Curiosity has been tracking the atmosphere in search of one of its great objectives, to verify the presence of methane in the atmosphere, a gas that in our planet is produced up to 95% by microorganisms.
His presence could have been a clue about the presence of current life on the red planet. At least on our planet it is a fairly effective biomarker (it does not have to be in other places). The harsh reality is that it has not been like that. The precise instruments of the rover have hardly found traces of methane, the estimated amount is just 1.3 parts per billion in the entire atmosphere, a sixth less than expected.
The fact that measurements are at ground level or at a single location should not influence the generalization of these values to the rest of the atmosphere.
@jsabino