Skip to main content

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.


Comments

Popular posts from this blog

How are animals becoming extinct?

   Since the animals have evolved species continue to become extinct. The most well-known example of extinct species is that of the dinosaurs. Often the species cannot adjust fast enough to the changing environmental conditions, or new species arise and displace the existing ones. Today, many species are becoming extinct because of the actions of humans. Elephants, big cats, and rhinos are hunted ruthlessly, forest areas are cleared, and the grey whales are endangered. These are only a few of the species mentioned in the ' Red List'. Do you know about 'Red List'?     'Red List' comes under organization IUCN (The International Union for Conservation of Nature). The list of endangered species is known as the Red List. It lists all those plant and animal species that  are facing the threat of extinction worldwide. The list is revised every 2 years. For the year 2006, the list contained around 16,000 species of plants and animals; 530 species more than t...

Our precious Environment and its Safety

Diversity of Species:      Deer, bears, salmons, pelicans, elephants, oaks, cacti, algae, lichens -any list illustrating the huge diversity of species on the Earth is inevitably and unending one. Many animals and plants inhabit our gardens; others live on high mountains or in colourful shimmering coral reefs. All of them have adapted to their environment in order to survive. This is all the more true in the case of animals that live in deserts or in extremely cold regions. Unfortunately, we are increasingly destroying the habitats of animals. We are clearing forests and polluting seas and coastal areas.  What do plants live on?     We know very well what animals eat. But what do plants do to live? almost all plants and animals need air, water, light, and nutrition to grow. Green plants use a complicated chemical process, called photosynthesis, to create energy for survival and growth. In this process the chloroplast inside the green leaves o...

The lifecycle of stars

Do we really know about a star?     Stars are heavenly bodies, which shine like our sun. Many shine brightly, the others have a dim glow. Some are red while others are blue. Stars are giant balls of gas made of hydrogen, bound together by their own force of gravity. The energy that makes them shine comes from a kind of power plant in their interior, where atomic nuclei of hydrogen atoms are fused together to form helium atoms. The stars do not live forever and ;die' at some point. Many simply get extinguished, while very heavy stars expand and explode. Their remains become either a neutron star of a 'black hole'.     The cradle of a star is a cloud of hydrogen and dust. There are numerous such clouds in the universe. By the action of external forces -such as the explosion of a star -this cloud gets compressed and keeps pulling itself together due to the increasing force of attraction among the particles. After a few hundreds of thousands of years, it begins to ...