Kamis, 12 Januari 2012

COMMUNICATION SATELLITE



               A spacecraft is placed in orbit around the Earth to intercept and retransmit radio signals. The communication satellite may also amplify,sort or route these signals.The communication function is similiar to a ground repeater relays communication satellite signals which connect many locations of both fixed and mobile over a wide area.
             There are two types of communication satellites of practical interest; passive and active. There is no amplification capability in a passive satellite; it simply reflects incident signals. passive communication satellite systems fall into two types: One uses large discrete structures, such as the Echo satellite and the other uses teh west ford approach in which a large volume of space is filled with a large number of tiny passive satellite. The general disadvantage of passive system is the limitation on message capacity resulting from the extremely low level of reradiated energy.
            In all active satellite system, complete electronic equipment for processing and transmission of signal must be carried. Also, means must be provided for directing antennas and maintaining desired satellite orientation and orbital position. with on-board alectronic processing capability, an active satellite can amplify,modify, and retransmit the signals as appropriate. Active satellite can also be considered as two basic types; the store-and-forward design and the massage real-time repeater.In the store and forward type,an Earth atation transmits a message to a satellite passing overhead.The massage is stored in an on board recorder and later played back through the satellite transmitter when the satellite passes over the appropriate Earth receiving station. The only communication satellite now considered for practical  use is real-time repeater.Operation of this instantaneous repeater requires the transmitting and receiving stations to be simultaneously in view of the spacecraft.
          The first satelite with the primary purpose of communication was score, launched on december 18th,1958.It received message from earth station in the United States and recorded them on tape for later transmission  when the satellite was over the receiving station. Echo 1,launced on august 12th,1960, was the first artificial satellite whose primary purpose was to provide real-time relay of message.It was a metallic coated plastic ballon 100ft(30m) in diameter which could only reflect the signal directed toward it. The American telephone and telegraph company developed and build Telstar,which was launced by NASA on july 10th 1962.It was the first active communication satellite with real time repeater. Telstar provided the first live television between the United States,europe,Japan,South America, on July 26th 1963.

Rabu, 11 Januari 2012

THE ASTRONOUTS



             An astronout is a person trained for flight beyond the earth's asmosphere.(in Russia, this spaceman is called Cosmonaut). The United States of Amerika and Russia have been sending astronout and cosmonauts into space several times every year since 1958. They leave the earth in large rocket ships,but when they are outside the atmosphere their small space capsules leave the ships. They go into orbit around the earth or continue their journey to the moon or,by the time some of you read this perhaps, to a planet.
          Both country have space programmes,and the two programmes are about the same. First they want to learn everything that they can about the new science of astronautics. In this sciencethey try to find ways to send man up in ships,to fly the ships in spsce and then to bring them back to the earth.
         In the other parthof the programmes the astronouts experiments and explore space. Through their explorations and experiment we are learning more about space, the other planets in our solar system, the moon, and the sun. But we are learning much more about our planet earth, too. For we can say that the earth itself  is a big space ship, carrying us thousands of miles through space every second.
         In 1959 the United States selected a total of 73 astronauts. The NASA (The National Aeronautics and Space Administration) selected the astonaut candidates. 43 of these astronauts flew in the Gemini, Apollo, Mercury, and skylap programme,the space laboratory programme. When 35  new astronaut  candidates where selected in 1978 for for the space Shuttle programme, 26 of the astronauts chosen earlier still had flight status. Six women were among the 35 new candidates selected for the space shuttle programme.

Senin, 09 Januari 2012

GALILEO GALILEI


             Galileo galilei was a great who initiated the scientist of the 17th century. He got his early education from aprivate tutor,and in 1581 he went a study medicine at the university of pisa. Because of his lack interest in medicine,he left university without a degree. Then concentrated his study on mathematics and physics. In 1589 he began his career in mathematics. He gave lectures on the subject at the university of pisa,where he was once a student.
           In 1592 the university of prague,Poland,invited Galileo to be a lecturer. He accepted the offer and gave lecture at the university for eighteen year. Here Galileo became interested in the study of star. At the time,most people still held a belief about heavenly bodies. As stated by ptolemy,a 2nd century Greek scientist, that "The earth was the centre of the universe, and that sun,the star,and all the other bodies in the sky moved around the earth". However.about thirty year before galileo was born,Copernicus, a polish scientist held a different view. He was the first scientist who get the idea.Tycho Brahe ,a Danish,who agreed to the idea that star and planets moved around the sun,but he believed  that the sun moved around the earth.
         Galileo's first know activity in Astronomy occured in 1604-1605, when a supernova aroused wide interest and speculation. In 1609 he completed his 9-power telescope, and in 1610 he made another one of 30-power. with the telescop he discovered that the moon was a sphere like our own earth,with mountains and valley. He also discovered many new stars and four of jupiter satellite.Galileo published these discoveries in his book Sidereus Nuncius (Starry Messenger,1610). The discoveries revealed the fact that the earth was not the centre of the heavenly bodies movement.  

Minggu, 08 Januari 2012

How To Make a Wayang Kulit




          Take athin piece of  buffalo skin which is large enough for the puppet.Clean the skin.Draw the puppeton the sin. Cut around your drawing with a sharp knife. Cut holes in the puppet where the light should go through. Take four small pieces of buffalo skin which are large enough for the upper arms and for the lower arms and hands.Clean the skin.Draw the arms and hands and cut around them.
        Paint all of the parts of the puppet.Take a long piece of buffalo horn,and cut a slitin it down the middle.Do not slit the big part of the horn.Put the horn into some very hot water until it become soft.Then dry it,and put the puppet in the slit in the horn. Bend the horn so that it goes along the middle of the body to the head. Fasten the horn to the puppet with string.
      Then fasten the upper arms to the body with string. Fasten the lower arms to the upper arms with string. Fasten a long piece of buffalo horn to each hand with string.

Visiting Museum

          Yesterday we went to a museum.It was a nice sunny say we arrived there about ten. We bought ticket for five persons. Before entering the museum,at the gate we saw abig and tall stone statue in the middle of a beautiful large round green park.
         In the museum we could find and old golden crown and many kinds of traditional weapon and jewelleries . In the next room there was a set of beautiful wooden carving jepara furniture, a gift from kartini's a father.At the back part of the museum there was a gallery with a tropical architecture.In this gallery we could see an antique bicycle,handicrafts,paintings,and old javanese and sundanese literature,an original ivory tusk,a big bamboo flute, and many other things.

Jumat, 06 Januari 2012

BALINESE PEOPLE



              Bali's total population of three million includes majority of hindu people and and the minority of Bali Aga people. The latter claim to be the indigeneous inhabitants of Bali. Their minority Status is the result of the immigration of javanese since the 10th century. Today, small communities of bali Aga can be found mainly in the eastern part of the island.
           Balinese society is stratified in two ways. The first -wangsa-is based on descent, in which each individual is born either into the nobility or the sudras (also know as jaba,which literally means,the outsider of the court). Whereas, the nobility consist of three castes,namely the priests (brahmanas), tehe ruling nobles(satriyas) and the warrior (wesyas).the majority of the population belong to the sudras. The second social "indicator" is based on one's place of residence. The banjar system forms a particular neigbourhood within the village. it is a male -dominating system and every Balinese male is required to belong to a banjar, women are excluded from membership. within each banjar, a member is elected head. The enjoy some minor privileges such as additional rice during festivals. In effect,the banjar functions like a cooperative, with common fund and even communal ownership of ricefields.

Kamis, 05 Januari 2012

THE HISTORY OF TEA

          Tea is easily the most popular drink in Britain today. Every year the British drink over 14 million litres of it,which is about four cups a day for every man,women and child in the country. Today the biggest tea-exporting countries in the world are india and srilangka and more than half the tea they export is drunk in britain. The British were not the first nation to drink tea. However,the Chinese were drinkingtea or as they called it tcha or tay (depending on which part of china they came from),for at least four thousand year before the first shipment of tea arrived in london in the late 1630s. It was supposed to have been drunk first by the Chinese emperor Shen Nung In 2737 BC. The Emporor was on journey and was resting under a bush, boiling some drinking water. The bush jush happened to be what botanists call a Cameillia Sinest or tea bush and some of the leaves accidentally fell into the pot of boiling water. The emperor liked what he drank and tea born. The british still use the slang expression char for tea,which is pronounced the same as the Cantonese word tcha.
        The British were not the first in europe to start drinking tea either. The Portugues, who where the first europeans to reach China by sea in 1513, no-ticed that the Chinese drank lots of strange smelling, hot,brown liquid for their health. The Chinese at first refused to sell any tcha or tay to the portugues,but eventually the portuguese were allowed to set up a trading station on a remote Chinese peninsular called Macao, Which enabled them to start shipping tea and other Chinese goods to Portugal.
       The first Englishman to arrive on tehe scene was Captain Weddell,who sailed into Macao harbour in 1637 wanting to do business. we have was not mada welcome  by to portugues or the Chinese and a battle started. The british had the more powerful guns. however ,and in the end, Captain Weddell was given permission to do some trading and set sail for london with a quantity of goods, including what someone on the ship described as a certain drink called char which is onlywater wiht kind of herb boiled in it.