Life on Mars
For many people, life on mars is a very fascinating theme. There are so many rumors about the Red Planet. We can find discussions, articles and scientific studies everywhere. There are also lots of films, usually science-fiction, like “Mars Attack”, “The Red Planet”, “Mission to Mars” and so on, which unfortunately don't contain any useful facts, except that Mars is red. When one says “life on Mars”, people usually imagine small green figures wandering around the galaxy and attacking any civilisation in their way.
So, is there any life on Mars? In my opinion yes. There is no reason to not to be, but it will not be like many people imagine; no big animals, no green figures, nor underground sci-fi-like bases. The life establishment on Mars is much more difficult than on Earth.
Firstly, scientists report the atmosphere has got the wrong composition for life. It doesn't contain the correct combination of gazes we are accustomed to, neither in minimal quantities. In addition, organisms can't live independently, at least this is the case on Earth, they must exchange materials between themselves. As we can see on Earth, plants produce oxygen used by animals, who produce C02 used by plants, and all dead material is decomposed by bacteria. This makes the atmosphere on Mars entirely different and hostile.
Secondly, it seems that there is no ozone layer, making a worldwide ozone hole. So theoretically, any living cell may be destroyed by the Sun's ultraviolet radiation. Some laboratory experiments show that the radiation can sterilise soil into depths of 10 cm.
Finally, the soil is also hostile for living forms. It is arid and very reactive, due to lack of water and radiation.
But I think, these facts aren't enough to say there is no life on Mars. Life there can be completely different. Organisms don't need to be oxygen or other earth-style materials dependent. Microorganisms are very resistant and can live in nearly any conditions of temperature or pressure. A couple of years ago, scientists discovered a meteorite containing substances, which are supposed to be produced by living organisms like those on Earth. And this meteorite was very probably from Mars. Organisms on Mars can be very well hidden, from the eyes of satellites and miniature robots, in the underground for example, like earthworms. However, the search for life on Mars has been until now unsuccessful.
Some people can think that further searches are a waste of time, while others remains eternally optimistic. Theoretically, it is simple to prove that there is life on Mars - all one need to do is find an example. And I believe it will happen. Let's wait for the next NASA mission to the Red Planet.
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