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What do we mean by space and how we conquer it?

Earlier outer space was the stuff of science fiction novels -today, about 800 artificial satellites are orbiting in space. These are specially designed flying machines, which encircle the Earth or the moon in fixed orbits. Numerous scientific probes were sent into space by various countries, and, since its establishment, the ISS has continued to enrich our knowledge of the endless universe and to open up possibilities of putting it to use. But our increasing activities in space have given rise to a new and serious problem: the accumulation of space debris.

How are satellites launched?

   Satellites are transported to space by carrier rockets. During the launch, the satellites mostly have a covering of metal, which protects them against wind, light, dust, air pressure, and the heat resulting from the friction they experience while passing at high speed through the atmosphere. This cover is discarded later on during the journey. During a satellite launch, the thrust of the carrier rockets is calculated in such a way that the satellite swing into its allotted position at the correct height and starts orbiting at a predetermined speed around the Earth. A television satellite thus revolves around the Earth once in exactly 24 hours. Solar sails draw energy from sunlight to generate the power needed to operate satellites.

But what do they do in spaces?

   Satellite -the original Latin word means 'bodyguards' -have different tasks. Some, like the METEOSAT, observe the weather, and others, like the SEASAT, measure temperatures on land and sea. There are also Earth-monitoring satellites, which monitor air and water pollution, and spying satellites, which can watch the goings-on in any country under focus. There are also television satellites, which transmit news from all parts of the world to our homes. There are also natural satellites, the moons of the planets -the moon we see in the night sky is one of them.

What are space probes?

   Space proves are unmanned spacecraft, which are sent into space to investigate celestial phenomena. Unlike a satellite, a space probe leaves the orbit of the Earth and flies to a remote destination, like Mars or Venus. Thus, for instance, the Soviet Union sent space probes, named Venera, to Venus in the 70s and the 80s in order to study the unique features of the hot planet. Some of them reached the surface of Venus and sent back radio signals to the Earth for about an hour. Then they failed because the surrounding pressure and temperature were too high for them to withstand. Other probes, however, have remained functional for longer periods of time. Thus, the probes Voyager 1 and Voyager 2 sent into space in 1977 are still sending back images of the depths f space. Both have now travelled beyond the solar system.


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