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A rusty desert

The first thing that you would see on the surface of Mars when looking at it through a telescope would be the general orange-red colour of the surface. The reddish colour of the planet, in fact is easily noticed by the naked eye. The areas showing this red tint have been called (deserts), but it must not be supposed that the deserts on Mars are just like the deserts on the Earth. Much work has gone into the study of the spectrum of the Martian deserts. There is definite evidence, that there are some sili­cates present — chemical substances similar to sand. But the main constituent is probably similar to limonite, a terrestrial mineral containing a great deal of red iron oxide. Because of the absence of oxygen in the planet's atmosphere, it is possible that any oxygen that might have been present has been used up oxydizing the planet. Mars may be a rusty planet!

If we were to attempt to summarize the conditions on Mars, we would liken them to conditions in a terrestrial desert if it were transported to the poles and raised into the stratosphere.

Seen through a telescope, the most prominent features of the Martian surface are the white polar caps. These caps are extensive in the Martian winter, and shrink and disappear in the Martian summer. A more careful study of Mars through a telescope also reveals a number of irregularly shaped dark blue-green markings. They are more or less permanent but they are not exactly constant in shape or appearance. In particular they show a variation of colour with the changing seasons on Mars in time with (he melt­ing of the polar caps, There have been many hypotheses put forward to explain the markings. It was suggested for instance that, because the general pattern of the markings seemed to follow the lines that one would expect for the prevailing winds on Mars, the markings might be composed of ash from volcanoes (although no volcano has ever been observed). Another hypothesis suggested that these markings are vegetation flourishing during the short Martian summer. But investigations of Mars by space probes8 includ­ing photographs of different areas of its surfaces showed that no vegetation is possible on the planet. Even primitive forms of life are highly doubtful.

Thus the results of space exploration obtained so far appear to confirm the idea that Mars is really a cold rusty lifeless desert.

Revision exercises

I. Translate the following sentences into Ukrainian paying attention to the Gerund.

1. Discovering the atomic structure was of great value for further research in nuclear physics. 2. We know of the Curies having discovered some new radioactive elements. 3. The experiments resulted in discovering the pro­cess of fission of atoms. 4. The scientists spoke about the necessity of discovering new inexhaustible sources of energy for space vehicles. 5. After discovering protons in1911 several investigators tried to describe the structure of the atom.

II. Translate the following sentences into Ukrainian paying attention to the different functions of the Gerund.

1. Energy is not lost by being utilized; it is only transformed. 2. We know of Geiger counter being capable to detect the presence of uranium ores in the earth. 3. The necessity of having an inexhaustible source of energy forsatellites led to the development of solar cells. 4. We know of Rutherford's having investigated the nature of alpha-particles. 5. After investigating several uranium compounds the scientists found that they gave off penetrating rays.