Introductory text to the planet Mars
Of the Mars is a rock planet and probably the most earth-like celestial body in our solar system. With its red appearance, Mars has fascinated humanity since antiquity. Because of its red color, the ancient Romans gave it the name of the Roman god of war Mars, in reference to spilled blood. In fact, oxidized iron causes the particular color on the Martian surface and in the thin atmosphere.
The red planet has with Phobos (Greek for 'fear') and Deimos (Greek for 'horror') two moons. These are probably asteroids captured by the gravitational field of Mars. Their shapes are not similar to those of a round moon, such as the moon of the earth, but rather reminiscent of misshapen boulders. In addition to the two moons, there are four asteroids in Mars' orbit ahead of Mars. These are called Trojans. At least another four Mars Trojans have been observed, but are still awaiting official confirmation from the Minor Planet Center.
In some ways, Mars is very similar to Earth. As the fourth planet of the solar system and neighbor planet Earth, Mars is located about 200 million kilometers from Earth. A day on Mars takes 24h and 40min. In addition, the inclination of the axis of 25 ° ensures a seasons climate (see: Origin of the seasons). The axial slope of the earth is 23.5 ° and is therefore almost identical. However, a year of Mars takes twice as long with 687 days, which also makes the seasons longer.
In terms of temperature, the average temperature on Mars is -50 ° C. Depending on the season and time of day, values between -85 ° C and + 20 ° C are possible. Also in this regard, Mars is most similar to Earth.
Mars - traces of water?
Mars is at the heart of extraterrestrial research because, under the climatic conditions of Mars, water could be in a liquid aggregate state, if only below the surface. The atmosphere is very thin and Mars has only a very weak magnetic field, which slows down solar winds inadequately. At the same time wind speeds of 400km / h sweep over the planet. If there was once water on the surface, this has now evaporated into space. The ice-covered polar ice caps also provide only small amounts of water. The frozen ice here, like the atmosphere of the planet, consists of carbon dioxide (CO2).
An indication of former water resources provides the planetary surface:
On the close-up, the dimensions of the relevant structures are barely discernible. Only from a bird's eye view, the deep ditches and dried river courses become clear, up to large river deltas, which have milled deep into the rock over millennia. And there are other indications that long ago large amounts of water were flowing over the planet. The found mineral Goethite, for example, which can only form 'under the presence' of liquid water. Furthermore, sediment deposits on Mars are comparable to those on Earth and traces of erosion leave little doubt that Mars once must have carried water.
Missions to Mars
From the beginning of the 60s began between the United States of America (USA) and the then Soviet Union, the race into space. Both nations wanted to show each other their technical superiority. This competition finally culminated in the moon landing from 1969. Also, Mars was chosen early as a target. In contrast to the moon, no crew should go there, but satellites aiming for a landing on Mars. The US and Soviet Union / Russia bring nearly 40 Mars missions. More than half of them failed. Most of the missions were well before the satellite was even in orbit. Out of 19 Soviet-Russian Mars missions, only one was a real success. Only since 1998 other nations have dared to try - with more or less great success.
The best-known and most promising Mars mission is currently the Mars Science Laboratory Program of NASA. In 2012, it succeeded in naming the Mars rover Curiosity to land on Mars.
The vehicle is still in operation. The goal of the mission is to prove that life on Mars was possible in the past. Curiosity seeks, e.g. after organic molecular compounds or certain chemical elements associated with life. So far, the project has cost over 2.5 billion dollars.
For the years from 2020, new Mars missions are already planned. This time, soil samples from Mars are to be returned to Earth. Because Curiosity is not designed to return to earth.
The project Mars One even pursues the goal of establishing a colony on Mars by 2027, without returning to Earth. Whether financially, but above all technically, the possibility exists to create a self-sufficient and long-term functioning ecosystem on Mars, is still very questionable. Mars One is not a project of NASA, but is trying to finance itself privately.