October 23, 2010 Category : Higher Studies
A theory of everything (TOE) is a hypothetical theory of theoretical physics that fully explains and links together all known physical phenomena. Initially, the term was used with an ironic connotation to refer to various overgeneralized theories. For example, a great-grandfather of Ijon Tichy — a character from a cycle of Stanisław Lem's science fiction stories of 1960s — was known to work on the "General Theory of Everything" (Polish: "Ogólna Teoria Wszystkiego"). Over time, the term stuck in popularizations of quantum physics to describe a theory that would unify or explain through a single model the theory.
There have been numerous theories of everything proposed by theoretical physicists.but as yet none have been able to stand up to experimental scrutiny as there is tremendous difficulty in getting the theories to produce experimentally testable results. The primary problem in producing a TOE is that the accepted theories of quantum
October 17, 2010 Category : Miscellaneous
Making the jump from military hardware to the police and civilian markets are these miniature UAVs called MicroDrones. Developed in Germany, they boast all kinds of brilliant features, ranging from GSM network communications to 3D controllability with what’s basically a Wiimote (more on that later). According to the Times (the UK Times), the bots have been or are going to be used by police departments to monitor rock concerts, football (soccer) crowds, and “antisocial behavior” in public parks. There’s also been interest from fire departments, environmental agencies, MI5, the Metropolitan police, and the Serious Organized Crime Agency (as opposed to the Joking Organized Crime Agency, I guess).
The MicroDrone is well suited to just about any mission you can dream up. It’s rugged, versatile, nearly silent, and can carry a 1kg payload for about 20 minutes (full specs here). Sure, that’s not the longest time, but you can always swap out batteries and send it right back up. The newest version of the bot is controlled through a GSM modem attached to an RC transmitter (the bot has its own SIM card installed). The remote just makes an ordinary phone call through a commercial GSM network to talk to the bot and send commands. Other features include automated GPS waypoint navigation (through what looks to be a Google Maps interface, no less), and a commercial digital camera mount. Each one of these little guys will set you back about $60,000 or you can rent one for 2 grand a month. More info and the video after the jump.
I’ve put together about 10 minutes worth of clips from the MicroDrone website illustrating the Wiimote usage as well as most of the rest of the features, along with some really cool airborne video and (if you can make it through to the end) a German chick in a bikini. And unfortunately, we don’t get too many chicks in bikinis here at BotJunkie, so enjoy it while you can.
October 16, 2010 Category : Jobs walk-in
|The Nobel Prize|
|Awarded for||Outstanding contributions in Physics, Chemistry, Literature, Peace, and Physiology or Medicine|
The Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel, identified with the Nobel Prize, is awarded for outstanding contributions in Economics.
|Presented by||Swedish Academy|
Royal Swedish Academy of Sciences
Norwegian Nobel Committee
Norway (Peace Prize only)
The Nobel Prizes (definite form, singular, Swedish: Nobelpriset, Norwegian: Nobelprisen) are annual international awards bestowed by Scandinavian committees in recognition of cultural and scientific advances. The will of the Swedish chemist Alfred Nobel, the inventor of dynamite, established the prizes in 1895. The prizes in Physics, Chemistry, Physiology or Medicine, Literature, and Peace were first awarded in 1901. The Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel was instituted by Sveriges Riksbank in 1968 and was first awarded in 1969. Although technically not a Nobel Prize, its announcements and presentations are made along with the other prizes, with the exception of the Peace Prize which is awarded in Oslo, Norway. Each Nobel Prize is regarded as the most prestigious award in its field.
The Royal Swedish Academy of Sciences awards the Nobel Prize in Physics, the Nobel Prize in Chemistry, and the Nobel Memorial Prize in Economic Sciences. The Nobel Assembly at Karolinska Institutet awards the Nobel Prize in Physiology or Medicine. The Swedish Academy grants the Nobel Prize in Literature. The Nobel Peace Prize is not awarded by a Swedish organisation but by the Norwegian Nobel Committee.
Each recipient, or laureate, is presented with a gold medal, a diploma, and a sum of money which depends on the Nobel Foundation's income that year. In 2009, each prize was worth 10 million SEK (c. US$1.4 million). The prize cannot be awarded posthumously, unless the winner of the prize has passed away after the prize's announcement. Nor may a prize be shared among more than three people. The average number of laureates per prize has increased substantially over the 20th century.
Alfred Nobel ( listen (help·info)) was born on 21 October 1833 in Stockholm, Sweden, into a family of engineers. He was a chemist, engineer, and inventor. In 1895 Nobel purchased the Bofors iron and steel mill, which he converted into a major armaments manufacturer. Nobel also invented ballistite, the immediate precurser to many smokeless military explosives. Nobel amassed a fortune during his lifetime, most of it from his 355 inventions, of which dynamite is the most famous. In 1888, Alfred had the unpleasant surprise of reading his own obituary, titled ‘The merchant of death is dead’, in a French newspaper. As it was Alfred's brother Ludvig who had died, the obituary was eight years premature. Alfred was disappointed with what he read and concerned with how he would be remembered. This inspired him to change his will. On 10 December 1896 Alfred Nobel died in his villa in San Remo, Italy, at the age of 63 from a cerebral haemorrhage.
To the surprise of many, Nobel's last will requested that his fortune be used to create a series of prizes for those who confer the "greatest benefit on mankind" in physics, chemistry, peace, physiology or medicine, and literature. Nobel wrote several wills during his lifetime. The last was written over a year before he died, signed at the Swedish-Norwegian Club in Paris on 27 November 1895. Nobel bequeathed 94% of his total assets, 31 million SEK (c. US$186 million in 2008), to establish the five Nobel Prizes. Because of the level of scepticism surrounding the will, it was not until 26 April 1897 that it was approved by the Storting in Norway. The executors of his will were Ragnar Sohlman and Rudolf Lilljequist, who formed the Nobel Foundation to take care of Nobel's fortune and organise the prizes.
Nobel's instructions named a Norwegian Nobel Committee to award the Peace Prize, the members of whom were appointed shortly after the will was approved in April 1897. Soon thereafter, the other prize-awarding organisations were established: the Karolinska Institutet on 7 June, the Swedish Academy on 9 June, and the Royal Swedish Academy of Sciences on 11 June. The Nobel Foundation reached an agreement on guidelines for how the prizes should be awarded, and in 1900, the Nobel Foundation's newly-created statutes were promulgated by King Oscar II. In 1905, the Union between Sweden and Norway was dissolved. Thereafter Norway's Nobel Committee remained responsible for awarding the Nobel Peace Prize and the Swedish institutions retained responsibility for the other prizes.
 Nobel Foundation
The Nobel Foundation was founded as a private organisation on 29 June 1900, to manage the finances and administration of the Nobel Prizes. In accordance with Nobel's will, the primary task of the Foundation is to manage the fortune Nobel left. Another important task of the Nobel Foundation is to market the prizes internationally and to oversee informal administration related to the prizes. The Foundation is not involved in the process of selecting the Nobel laureates. In many ways the Nobel Foundation is similar to an investment company, in that it invests Nobel's money to create a solid funding base for the prizes and the administrative activities. The Nobel Foundation is exempt from all taxes in Sweden (since 1946) and from investment taxes in the United States (since 1953). Since the 1980s, the Foundation's investments have become more profitable and as of 31 December 2007, the assets controlled by the Nobel Foundation amounted to 3.628 billion Swedish kronor (c. US$560 million).
According to the statutes, the Foundation should consist of a board of five Swedish or Norwegian citizens, with its seat in Stockholm. The Chairman of the Board should be appointed by the Swedish King in Council, with the other four members appointed by the trustees of the prize-awarding institutions. An Executive Director is chosen from among the board members, a Deputy Director is appointed by the King in Council, and two deputies are appointed by the trustees. However, since 1995 all the members of the board have been chosen by the trustees, and the Executive Director and the Deputy Director appointed by the board itself. As well as the board, the Nobel Foundation is made up of the prize-awarding institutions (the Royal Swedish Academy of Sciences, the Nobel Assembly at Karolinska Institute, the Swedish Academy, and the Norwegian Nobel Committee), the trustees of these institutions, and auditors.
 First prizes
Once the Nobel Foundation and its guidelines were in place, the Nobel Committees began collecting nominations for the inaugural prizes; subsequently they sent a list of preliminary candidates to the prize-awarding institutions. The Norwegian Nobel Committee had appointed prominent figures including Jørgen Løvland, Bjørnstjerne Bjørnson and Johannes Steen to give the Nobel Peace Prize credibility. The committee awarded the Peace Prize to two prominent figures in the growing peace movement around the end of the 19th century: Frédéric Passy was co-founder of the Inter-Parliamentary Union and Henry Dunant was founder of the International Committee of the Red Cross.
The Nobel Committee's Physics Prize shortlist cited Wilhelm Conrad Röntgen's discovery of X-rays and Philipp Lenard's work on cathode rays. The Academy of Sciences selected Röntgen for the prize. In the last decades of the 19th century many chemists had made significant advances in their subject. Thus, with the Chemistry Prize, the Academy "was chiefly faced with merely deciding the order in which these scientists should be awarded the prize." The Academy received 20 nominations, eleven of them for Jacobus van't Hoff. Van't Hoff was awarded the prize for his contributions in chemical thermodynamics.
The Swedish Academy chose the poet Sully Prudhomme for the first Nobel Prize in Literature. A group including 42 Swedish writers, artists and literary critics protested against this decision, having expected Leo Tolstoy to win. Some, including Burton Feldman, have criticised this prize because they consider Prudhomme a mediocre poet. Feldman's explanation is that most of the Academy members preferred Victorian literature and thus selected a Victorian poet. The first Physiology or Medicine Prize went to the German physicist and microbiologist Emil von Behring. During the 1890s, von Behring developed an antitoxin to treat diphtheria, which until then was causing thousands of deaths each year.
 World War II
In 1938 and 1939, Adolf Hitler's Third Reich forbade three laureates from Germany (Richard Kuhn, Adolf Friedrich Johann Butenandt, and Gerhard Domagk) from accepting their prizes. Each man was later able to receive the diploma and medal. Even though Sweden was officially neutral during World War II, the prizes were awarded irregularly. In 1939 the Peace Prize was not awarded. No prize was awarded in any category from 1940–42, due to the occupation of Norway by Germany. In the subsequent year, all prizes were awarded except those for literature and peace.
During the occupation of Norway, three members of the Norwegian Nobel Committee fled into exile. The remaining members escaped persecution from the Nazis when the Nobel Foundation stated that the Committee building in Oslo was Swedish property. Thus it was a safe haven from the German military, which was not at war with Sweden. These members kept the work of the Committee going but did not award any prizes. In 1944 the Nobel Foundation, together with the three members in exile, made sure that nominations were submitted for the Peace Prize and that the prize could be awarded once again.
 Prize in Economic Sciences
Sveriges Riksbank celebrated its 300th anniversary in 1968 by donating a large sum of money to the Nobel Foundation. The following year, the Nobel Memorial Prize in Economic Sciences was awarded for the first time. The Royal Swedish Academy of Sciences became responsible for selecting laureates. The first laureates for the Economics Prize were Jan Tinbergen and Ragnar Frisch "for having developed and applied dynamic models for the analysis of economic processes." Although not technically a Nobel Prize, it is identified with the awards; its winners are announced with the Nobel Prize recipients, and the Prize in Economic Sciences is presented at the Swedish Nobel Prize Award Ceremony. The Board of the Nobel Foundation decided that after this addition, it would allow no further new prizes.
 Recent laureates
|This section may need to be updated. Please update this section to reflect recent events or newly available information, and remove this template when finished. Please see the talk page for more information.|
In 2008 the Physiology or Medicine Prize was shared among three virologists. French team Luc Montagnier and Françoise Barré-Sinoussi together shared half the prize for discovering that the virus now known as HIV causes AIDS. Harald zur Hausen shared the prize for his discovery that the human papilloma virus causes cervical cancer. The Chemistry Prize was shared among three biologists; Osamu Shimomura, Martin Chalfie and Roger Tsien isolated and developed the green fluorescent protein from a jellyfish. The GFP has important applications in many areas of cell biology and biotechnology. Martti Ahtisaari received the Peace Prize "for his important efforts, on several continents and over more than three decades, to resolve international conflicts." The Physics Prize was awarded to Yoichiro Nambu, Makoto Kobayashi and Toshihide Maskawa for the discovery of the mechanism of spontaneous broken symmetry in subatomic physics. Jean-Marie Gustave Le Clézio received the Literature Prize and was described as an "author of new departures, poetic adventure and sensual ecstasy, explorer of a humanity beyond and below the reigning civilisation." The Economics Prize was awarded to Paul Krugman for his work on international trade and economic geography.
In 2009 the Chemistry Prize was awarded to Venkatraman Ramakrishnan, Thomas Steitz, and Ada Yonath, for their work on the structure and function of the ribosome. The Physics Prize was awarded to Charles K. Kao for his research on the transmission of light through optical fibres and to Willard S. Boyle and George E. Smith for inventing a sensor that turns light into electrical signals, which made inventions such as the digital camera possible. Elinor Ostrom and Oliver E. Williamson were awarded the Economics Prize for "their work in economic governance, especially the commons." Ostrom was the first woman to receive the Economics Prize. The Physiology or Medicine Prize was awarded to Elizabeth H. Blackburn, Carol W. Greider, and Jack W. Szostak for their research on telomeres. The Literature Prize was awarded to Herta Müller "who, with the concentration of poetry and the frankness of prose, depicts the landscape of the dispossessed." The President of the United States, Barack Obama, was awarded the Peace Prize "for his extraordinary efforts to strengthen international diplomacy and cooperation between peoples."
 Award process
The award process is similar for all of the Nobel Prizes; the main difference is in who can make nominations for each of them.
Nomination forms are sent by the Nobel Committee to about 3000 individuals, usually in September the year before the prizes are awarded. These individuals are often academics working in a relevant area. For the Peace Prize, inquiries are sent to governments, members of international courts, professors and rectors, former Peace Prize laureates and current or former members of the Norwegian Nobel Committee. The deadline for the return of the nomination forms is 31 January of the year of the award. The Nobel Committee nominates about 300 potential laureates from these forms and additional names. The nominees are not publicly named, nor are they told that they are being considered for the prize. All nomination records for a prize are sealed for 50 years from the awarding of the prize.
The Nobel Committee then prepares a report, drawn from the advice of experts in the relevant fields. This, along with the list of preliminary candidates, is submitted to the prize-awarding institutions. The institutions meet to choose the laureate or laureates in each field by a majority vote. Their decision, which cannot be appealed, is announced immediately after the vote. A maximum of three laureates and two different works may be selected per award. Except for the Peace Prize, which can be awarded to institutions, the awards can only be given to individuals. If the Peace Prize is not awarded, the money is split among the scientific prizes. This has happened 19 times so far.
 Posthumous nominations
Although posthumous nominations are not permitted, individuals who died in the months between their nomination and the decision of the prize committee were originally eligible to receive the prize. This occurred twice: the 1931 Literature Prize awarded to Erik Axel Karlfeldt, and the 1961 Peace Prize awarded to UN Secretary General Dag Hammarskjöld. Since 1974, laureates must be alive at the time of the October announcement. There has been one laureate, William Vickrey, who died after the prize was announced but before it could be presented.
 Recognition time lag
Nobel's will provides for prizes to be awarded in recognition of discoveries made "during the preceding year". During the early years, the awards usually recognised recent discoveries. However, some of these early discoveries were later discredited.[n 1] To avoid this embarrassment, the awards increasingly recognised scientific discoveries that had withstood the test of time. According to Ralf Pettersson, former chairman of the Nobel Prize Committee for Physiology or Medicine, "the criterion ‘the previous year’ is interpreted by the Nobel Assembly as the year when the full impact of the discovery has become evident."
The interval between the award and the accomplishment it recognises varies from discipline to discipline. The Literature Prize is typically awarded to recognise a cumulative lifetime body of work rather than a single achievement. The Peace Prize can also be awarded for a lifetime body of work. For example 2008 winner Martti Ahtisaari was awarded for his work to resolve international conflicts. However, they can also be awarded for specific recent events. For instance, Kofi Annan was awarded the 2001 Peace Prize just four years after becoming the Secretary-General of the United Nations. Similarly Yasser Arafat, Yitzhak Rabin, and Shimon Peres received the 1994 award, about a year after they successfully concluded the Oslo Accords.
Awards for physics, chemistry, and medicine require that the significance of the achievement is "tested by time." In practice, the lag between the discovery and the award is typically 20 or more years. For example, Subrahmanyan Chandrasekhar shared the 1983 Physics Prize for his 1930s work on stellar structure and evolution. Not all scientists live long enough for their work to be recognised. Some discoveries can never be considered for a prize if their impact is realised after the discoverers have died.
 Award ceremonies
Apart from the Peace Prize, the Nobel Prizes are presented in Stockholm, Sweden, at the annual Prize Award Ceremony on 10 December, the anniversary of Nobel's death. The recipients' lectures are normally held in the days prior to the award ceremony. The Peace Prize and its recipients' lectures are presented at the annual Prize Award Ceremony in Oslo, Norway, usually on 10 December. The award ceremonies and the associated banquets are typically major international events. The Prizes awarded in Sweden's ceremonies' are held at the Stockholm Concert Hall, with the Nobel banquet following immediately at Stockholm City Hall. The Nobel Peace Prize ceremony has been held at the Norwegian Nobel Institute (1905–1946); at the auditorium of the University of Oslo (1947–1989); and at Oslo City Hall (1990–).
The highlight of the Nobel Prize Award Ceremony in Stockholm occurs when each Nobel Laureate steps forward to receive the prize from the hands of the King of Sweden. In Oslo, the Chairman of the Norwegian Nobel Committee presents the Nobel Peace Prize in the presence of the King of Norway. Since 1902, the King of Sweden has presented all the prizes, except the Peace Prize, in Stockholm. At first King Oscar II did not approve of awarding grand prizes to foreigners, but is said to have changed his mind once his attention had been drawn to the publicity value of the prizes for Sweden.
 Nobel banquet
After the award ceremony in Sweden a banquet is held at the Stockholm City Hall, which is attended by the Swedish Royal Family and around 1,300 guests. The banquet features a three-course dinner, entertainment and dancing and is extensively covered by local and international media. Before 1930, the banquet in Sweden was held in the ballroom of Stockholm's Grand Hotel.
The Nobel Peace Prize banquet is held in Oslo at the Grand Hotel after the award ceremony. As well as the laureate, other guests include the President of the Storting, the Prime Minister and (since 2006) the King and Queen of Norway. In total there are about 250 guests attending who all are treated a five-course meal. For the first time in its history, the banquet was cancelled in Oslo in 1979 because the laureate Mother Teresa refused to attend, saying the money would be better spent on the poor. Mother Teresa used the US$7,000 that was to be spent on the banquet to hold a dinner for 2,000 homeless people on Christmas Day.
 Nobel lectures
According to the statutes of the Nobel Foundation, each laureate is required to give a public lecture on a subject related to the topic of their prize. These lectures normally occur during Nobel Week[n 2] before the award ceremony, but this is not mandatory. The laureate is only obliged to give the lecture within six months of receiving the prize. Some have happened even later. For example, US president Theodore Roosevelt won the Peace Prize in 1906 but gave his lecture in 1910, after his term in office. The lectures are organised by the same association who selected the laureates.
The Nobel Prize medals, minted by Myntverket in Sweden and the Mint of Norway since 1902, are registered trademarks of the Nobel Foundation. Each medal features an image of Alfred Nobel in left profile on the obverse. The medals for physics, chemistry, physiology or medicine, and literature have identical obverses, showing the image of Alfred Nobel and the years of his birth and death. Nobel's portrait also appears on the obverse of the Peace Prize medal and the medal for the Economics Prize, but with a slightly different design. For instance, the laureate's name is engraved on the rim of the Economics medal. The image on the reverse of a medal varies according to the institution awarding the prize. The reverse sides of the medals for chemistry and physics share the same design.
All medals made before 1980 were struck in 23 carat gold. Since then they have been struck in 18 carat green gold plated with 24 carat gold. The weight of each medal varies with the value of gold, but averages about 175 grams (0.39 lb) for each medal. The diameter is 66 millimetres (2.6 in) and the thickness varies between 5.2 millimetres (0.20 in) and 2.4 millimetres (0.094 in). Because of the high value of their gold content and tendency to be on public display, Nobel medals are subject to medal theft. During World War II, the medals of German scientists Max von Laue and James Franck were sent to Copenhagen for safekeeping. When Germany invaded Denmark, chemist George de Hevesy dissolved them in aqua regia, to prevent confiscation by Nazi Germany and to prevent legal problems for the holders. After the war, the gold was recovered from solution, and the medals re-cast.
Nobel laureates receive a diploma directly from the hands of the King of Sweden or the Chairman of the Norwegian Nobel Committee. Each diploma is uniquely designed by the prize-awarding institutions for the laureates that receive them. The diploma contains a picture and text which states the name of the laureate and normally a citation of why they received the prize. None of the Nobel Peace Prize laureates has ever had a citation on their diplomas.
 Award money
The laureates are given a sum of money when they receive their prizes, in the form of a document confirming the amount awarded. The amount of prize money depends upon how much money the Nobel Foundation can award each year. The purse has increased since the 1980s, when the prize money was 880 000 SEK (c. 2.6 million SEK or US$350 000 today). In 2009, the monetary award was 10 million SEK (US$1.4 million). If there are two winners in a particular category, the award grant is divided equally between the recipients. If there are three, the awarding committee has the option of dividing the grant equally, or awarding one-half to one recipient and one-quarter to each of the others. It is not uncommon for recipients to donate prize money to benefit scientific, cultural, or humanitarian causes.
 Controversies and criticisms
 Controversial recipients
Among other criticisms, the Nobel Committees have been accused of having a political agenda, and of omitting more deserving candidates. They have also been accused of Eurocentrism. This is especially true for the Literature Prize.
One of the controversial Peace Prizes was the 2009 Nobel Peace Prize awarded to Barack Obama. Nominations had closed only eleven days after Obama took office as President, but the actual evaluation occurred over the next eight months. Obama himself stated that he did not feel he deserved the award, and that he did not feel worthy of the company the award would place him in. Past winners of the Peace Prize were divided, some saying that Obama deserved the award, and others saying he had not yet earned it. Obama's award, along with the previous Peace Prizes for Jimmy Carter and Al Gore, prompted accusations of a left-wing bias.
Among the most criticised Nobel Peace Prizes was the one awarded to Henry Kissinger and Lê Ðức Thọ, who later declined the prize. This led to two Norwegian Nobel Committee members resigning. Kissinger and Thọ were awarded the prize for negotiating a ceasefire between North Vietnam and the United States in January 1973. However, when the award was announced hostilities still occurred from both sides. Many critics were of the opinion that Kissinger was not a peace-maker but the opposite; responsible for widening the war.
Yasser Arafat, Shimon Peres, and Yitzhak Rabin received the Peace Prize in 1994 for their efforts in making peace between Israel and Palestine. According to journalist Caroline Frost many issues, such as the plight of Palestinian refugees, had not been addressed and no lasting peace was established between Israel and Palestine. Immediately after the award was announced one of the five Norwegian Nobel Committee members denounced Arafat as a terrorist and resigned. Additional misgivings about Arafat were widely expressed in various newspapers.
The award of the 2004 Literature Prize to Elfriede Jelinek drew a protest from a member of the Swedish Academy, Knut Ahnlund. Ahnlund resigned, alleging that selecting Jelinek had caused "irreparable damage to all progressive forces, it has also confused the general view of literature as an art." He alleged that Jelinek's works were "a mass of text shovelled together without artistic structure." The 2009 Literature Prize to Herta Müller also generated criticism. According to The Washington Post many US literary critics and professors had never previously heard of her. This made many feel that the prizes were too Eurocentric.
In 1949, the Portuguese neurologist António Egas Moniz received the Physiology or Medicine Prize for his development of the prefrontal leucotomy. The previous year Dr. Walter Freeman had developed a version of the procedure which was faster and easier to carry out. Due in part to the publicity surrounding the original procedure, Freeman's procedure was prescribed without due consideration or regard for modern medical ethics. Endorsed by such influential publications as The New England Journal of Medicine, lobotomy became so popular that about 5,000 lobotomies were performed in the United States in the three years immediately following Moniz's receipt of the Prize.
 Overlooked achievements
The Norwegian Nobel Committee confirmed that Mahatma Gandhi was nominated for the Peace Prize in 1937–39, 1947 and a few days before he was assassinated in January 1948. Later members of the Norwegian Nobel Committee expressed regret that he was not given the prize. In 1948, the year of Gandhi's death, the Nobel Committee declined to award a prize on the grounds that "there was no suitable living candidate" that year. Later, when the Dalai Lama was awarded the Peace Prize in 1989, the chairman of the committee said that this was "in part a tribute to the memory of Mahatma Gandhi." Other high profile individuals with widely recognised contributions to peace have been missed out. As well as Gandhi, Foreign Policy lists Eleanor Roosevelt, Václav Havel, Ken Saro-Wiwa, Sari Nusseibeh and Corazon Aquino as people who "never won the prize, but should have."
The Literature Prize also has controversial omissions. Adam Kirsch has suggested that many notable writers have missed out on the award for political or extra-literary reasons. The heavy focus on European and Swedish authors has been a subject of criticism. The Eurocentric nature of the award was acknowledged by Peter Englund, the 2009 Permanent Secretary of the Swedish Academy, as a problem with the award and was attributed to the tendency for the academy to relate more to European authors. Notable writers that have been overlooked for the Literature Prize include; Émile Zola, Jorge Luis Borges, Marcel Proust, Ezra Pound, James Joyce, August Strindberg, John Updike, Arthur Miller, Graham Greene and Mark Twain.
The strict rule against awarding a prize to more than three people at once is also controversial. When a prize is awarded to recognise an achievement by a team of more than three collaborators one or more will miss out. For example, in 2002, the prize was awarded to Koichi Tanaka and John Fenn for the development of mass spectrometry in protein chemistry, an award that did not recognise the achievements of Franz Hillenkamp and Michael Karas of the Institute for Physical and Theoretical Chemistry at the University of Frankfurt. Similarly, the prohibition of posthumous awards fails to recognise achievements by an individual or collaborator who dies before the prize is awarded. In 1962, Francis Crick, James D. Watson, and Maurice Wilkins were awarded the Physiology or Medicine Prize for discovering the structure of DNA. Rosalind Franklin, a key contributor in that discovery, died of ovarian cancer four years earlier.
 Emphasis on discoveries over inventions and theories
Alfred Nobel left his fortune to finance annual prizes to be awarded "to those who, during the preceding year, shall have conferred the greatest benefit on mankind." He stated that the Nobel Prizes in Physics should be given "to the person who shall have made the most important 'discovery' or 'invention' within the field of physics." Nobel did not emphasise discoveries, but they have historically been held in higher respect by the Nobel Prize Committee than inventions: 77% of the Physics Prizes have been given to discoveries, compared with only 23% to inventions. Christoph Bartneck and Matthias Rauterberg, in papers published in Nature and Technoetic Arts, have argued this emphasis on discoveries has moved the Nobel Prize away from its original intention of rewarding the greatest contribution to society.
An example where discovery has been preferred over theory is Albert Einstein's prize. His 1921 Physics prize recognised his discovery of the photoelectric effect rather than his Special Theory of Relativity. Historian Robert Friedman proposes that this may be due to the Nobel Prize Committee's discrimination against theoretical science.
 Specially distinguished laureates
 Multiple laureates
Four people have received two Nobel Prizes. Maria Skłodowska-Curie received the Physics Prize in 1903 for the discovery of radioactivity and the Chemistry Prize in 1911 for the isolation of pure radium. Linus Pauling won the 1954 Chemistry Prize for his research into the chemical bond and its application to the structure of complex substances. Pauling also won the Peace Prize in 1962 for his anti-nuclear activism, making him the only winner of two unshared prizes. John Bardeen received the Physics Prize twice: in 1956 for the invention of the transistor and in 1972 for the theory of superconductivity. Frederick Sanger received the prize twice in Chemistry: in 1958 for determining the structure of the insulin molecule and in 1980 for inventing a method of determining base sequences in DNA.
Two organisations have received the Peace Prize multiple times. The International Committee of the Red Cross received it three times: in 1917 and 1944 for its work during the world wars, and in 1963 during the year of its centenary. The United Nations High Commissioner for Refugees has won the Peace Prize twice for assisting refugees: in 1954 and 1981.
 Family laureates
The Curie family has received the most prizes, with five. Maria Skłodowska-Curie received the prizes in Physics (in 1903) and Chemistry (in 1911). Her husband, Pierre Curie, shared the 1903 Physics prize with her. Their daughter, Irène Joliot-Curie, received the Chemistry Prize in 1935 together with her husband Frédéric Joliot-Curie. In addition, the husband of Maria Curie's second daughter, Henry Labouisse, was the director of UNICEF when it won the Nobel Peace Prize in 1965.
Although no family matches the Curie family's record, there have been several with two laureates. Gunnar Myrdal received the Economics Prize in 1974 and his wife, Alva Myrdal, received the Peace Prize in 1982. J. J. Thomson was awarded the Physics Prize in 1906 for showing that electrons are particles. His son, George Paget Thomson, received the same prize in 1937 for showing that they also have the properties of waves. William Henry Bragg together with his son, William Lawrence Bragg, shared the Physics Prize in 1915. Niels Bohr won the Physics prize in 1922, and his son, Aage Bohr, won the same prize in 1975. Manne Siegbahn, who received the Physics Prize in 1924, was the father of Kai Siegbahn, who received the Physics Prize in 1981. Hans von Euler-Chelpin, who received the Chemistry Prize in 1929, was the father of Ulf von Euler, who was awarded the Physiology or Medicine Prize in 1970. C.V. Raman won the Physics Prize in 1930 and was the uncle of Subrahmanyan Chandrasekhar, who won the same prize in 1983. Arthur Kornberg received the Physiology or Medicine Prize in 1959. Kornberg's son, Roger later received the Chemistry Prize in 2006. Jan Tinbergen, who won the first Economics Prize in 1969, was the brother of Nikolaas Tinbergen, who received the 1973 Physiology or Medicine Prize.
 Refusals and constraints
Two laureates have voluntarily declined the Nobel Prize. Jean-Paul Sartre was awarded the Literature Prize in 1964 but refused, stating, "A writer must refuse to allow himself to be transformed into an institution, even if it takes place in the most honourable form." The other is Lê Ðức Thọ, chosen for the 1973 Peace Prize for his role in the Paris Peace Accords. He declined, claiming there was no actual peace in Vietnam.
During the Third Reich, Adolf Hitler hindered Richard Kuhn, Adolf Butenandt, and Gerhard Domagk from accepting their prizes. All of them were awarded their diplomas and gold medals after World War II. In 1958, Boris Pasternak declined his prize for literature due to fear of what the Soviet Union government would do if he travelled to Stockholm to accept his prize. In return, the Swedish Academy refused his refusal, saying "this refusal, of course, in no way alters the validity of the award." The Academy announced with regret that the presentation of the Literature Prize could not take place that year, holding it until 1989 when Pasternak's son accepted the prize on his behalf.
October 16, 2010 Category : Miscellaneous
How Satellites Work
|What is a Satellite?||Geostationary (GOES) Satellites|
|What are the components |
of a human-made satellite?
|Mission to Planet Earth|
|How are satellites launched?||Topex/Poseidon|
|Why does a satellite stay in orbit?||SeaWIFS|
|Navigation Satellites||Mir Space Station|
|Weather Satellites||Tracking "Space Junk"|
|Polar Orbiting Satellites||OSCAR Satellites|
These links take you to subsections of this page. You can scroll down the entire page, or jump to a topic of interest.
In little more than a generation, the launching of a satellite has gone from stopping the nation's business to guaranteeing that it runs like clockwork. Today, satellites, like clocks, telephones, and computers, are commonplace tools of technology. They help us navigate, communicate, monitor the environment, and forecast weather. Appropriately, the word satellite means an "attendant."
In 1957, the launching of the Russian satellite Sputnik changed the course of our nation. The United States immediately launched massive efforts to compete in a breakneck Race to the Moon. In the space of a decade, our nation of armchair explorers sat glued to their television sets while Alan Shepard went up and back in a Mercury capsule in 1961, as John Glenn circled the globe 3 times in 1962, and as Neil Armstrong set foot on the moon in 1969.
That sense of discovery has muted over time as we became accustomed to the miracles of space travel. The launching of a Space Shuttle mission may not even come up in a class discussion of current events, yet satellites bring those same students the ability to watch the Olympics, the weather, and news of other events from around the world that are considered "newsworthy."
A satellite is an object that goes around, or orbits, a larger object, such as a planet. While there are natural satellites, like the moon, hundreds of man-made satellites also orbit the Earth.
Communications antennae, radio receivers and transmitters enable the satellite to communicate with one or more ground stations, called command centers. Messages sent to the satellite from a ground station are "uplinked"; messages transmitted from the satellite to Earth are "downlinked."
Many satellites are powered by rechargeable batteries, taking advantage of the ultimate battery charger, the sun. Silvery solar panels are prominent features on many satellites. Other satellites have fuel cells that convert chemical energy to electrical energy, while a few rely on nuclear energy. Small thrusters provide attitude, altitude, and propulsion control to modify and stabilize the satellite's position in space.
Specialized systems accomplish the tasks assigned to the satellite. These often include sensors capable of imaging a range of wavelengths. Telecommunications satellites require no optics, while environmental satellites do. Environmental satellites transmit images as numbers to a computer on Earth, which translates this digital data into images.
Some of the data can be enhanced to look like photographs. Bright colors (false colors) are often added to enhance the contrast, make details stand out, or allow us to see what was recorded in the wavelengths beyond our visual range. The false colors do not necessarily correspond to the colors we expect to see. For example, a field of wheat might look pink; clear water may appear black.
The trick to launching a satellite is getting it high enough to do its job without losing the capsule to outer space. It's a delicate balance of push and pull, accomplished by the inertia of the moving object and the Earth's gravity. If you launch a satellite at 17,000 mph, the forward momentum will balance gravity, and it will circle the Earth. On the other hand, if the satellite is launched faster than 23,500 mph, it will leave the gravitational pull of the Earth.
Due to the balance of two effects:
To illustrate this principle, attach a small weight or a ball to a string, and swing it around in a circle. If the string were to break, the ball would fly off in a straight line. But because it is tethered (like gravity tethers a satellite), it orbits your hand.
Imagine that you could climb an imaginary mountain whose summit pokes above the Earth's atmosphere (it would be about ten times higher than Mt. Everest). If you threw a baseball from the mountain top, it would fall to the ground in a curving path. Two motions act upon it: travelling in a straight line and falling toward Earth. The faster you throw the ball, the farther it will go before it hits the ground. If you could throw the ball at a speed of 17,000 mph, the ball wouldn't reach the ground. It would circle the Earth in a curved path; it would be in orbit. (It would be traveling at 5 miles per second and take about 10 minutes to cross the United States.) This is the speed needed to put satellites into orbit, which is why the Space Shuttle and other satellites require such powerful boosters.
Human-made satellites circle the Earth in two special ways: polar orbits and geostationary orbits.
A satellite in a polar orbit travels over the North and South Poles. A polar orbit may be several hundred miles to several thousand miles above Earth. A satellite in a relatively low orbit circles the Earth approximately 14 times each day, while higher-orbiting satellites orbit less frequently. Because the Earth is turning more slowly than the satellite, the satellite gets a slightly different view on every revolution. Over the course of a few days, a satellite in a polar orbit will cover almost all of the planet.
A satellite in a high-altitude, geostationary orbit circles the Earth once every 24 hours, the same amount of time it takes for the Earth to spin on its axis. The satellite turns eastward (like our Earth) along the Equator. It stays above the same point on Earth all the time. To maintain the same rotational period as the Earth, a satellite in geostationary orbit must be 22,237 miles above the Earth. At this distance, the satellite can view half of the Earth's surface. (Its viewing area is called its "footprint.") Because the high-altitude satellite appears to remain fixed in one position (it's really orbiting at the same rate as the Earth turns), it requires no tracking to receive its downlink signal. That is why when we turn our home satellite dish to receive the TV signal from a particular geostationary satellite, we don't have to keep jumping up to adjust its position.
One of the advantages of geostationary satellites is that imagery is obtained and displayed constantly, compared to imagery transmitted more sporadically by low Earth-orbiting platforms.
Most satellites serve one or more functions:
Back to Top
Communications satellites have a quiet, yet profound, effect on our daily lives. They link remote areas of the Earth with telephone and television. Modern financial business is conducted at high speed via satellite. Newspapers such as USA Today and The Wall Street Journal are typeset and then transmitted to printing plants around the country via satellite.
Radio signals near the microwave frequency range are best suited to carry large volumes of communications traffic, because they are not deflected by the Earth's atmosphere as lower frequencies are. Basically, they travel in a straight line, known as "line-of-sight communication." If someone in San Francisco tried to beam a microwave signal directly to Hawaii, it would never get there; it would disappear into space or dissipate into the ocean. Over short distances, we erect microwave towers every 25 miles or so to act as "repeaters" to repeat and boost the signal. Think of a geostationary communications satellite as a repeater in the sky.
Where am I? Where do I want to go? How can I get there? These are questions we've all asked at one time or another. Satellites for navigation were developed in the late 1950s as a direct result of surface ships and submarines needing to know exactly where they were at any given time. In the middle of the ocean out of sight of land, one can't determine an accurate position by looking out the window.
The idea of using satellites for navigation began with the launch of Sputnik 1 on October 4, 1957. Monitoring that satellite, scientists at Johns Hopkins University's Applied Physics Laboratory noticed that when the transmitted radio frequency was plotted on a graph, a curve characteristic of the Doppler shift appeared. By studying this apparent change of radio frequency as the satellite passed overhead, they were able to show that the Doppler shift, when properly used, described the orbit of the satellite.
Most navigation systems use time and distance to calculate location. Early on, scientists recognized the principle that, given velocity and the time required for a radio signal to be transmitted between two points, the distance between the two points can be computed. To do this calculation, a precise, synchronized departure time and measured arrival time of the radio signal must be obtained. By synchronizing the signal transmission time between two precise clocks, one in a satellite and one at a ground-based receiver, the transit time could be measured and then multiplied by the speed of light to obtain the distance between the two positions.
This three-dimensional satellite navigational system (NAVSTAR) enables a traveler to obtain his or her position anywhere on or above the planet. Data transmitted from the satellite provides the user with time, precise orbital position of the satellite, and the position of other satellites in the system. Currently, there is a full constellation of 24 orbiting satellites devoted to navigation.
Using a commercial Global Positioning System (GPS) locator, the user can calculate distance by measuring the time it takes for the satellite's radio transmissions, traveling at the speed of light, to reach the receiver. Once distance from four satellites is known, position in three dimensions (latitude, longitude, and altitude) can be calculated by triangulation, and velocity in three dimensions can be computed from the Doppler shift in the received signal. The new GPS receivers do all of the work; a traveler simply turns on the unit, makes certain that it's locked onto at least four satellites, and the precise position of the GPS unit is displayed automatically. One innovative application of GPS technology is to determine Earth's ground movement after an earthquake. Referencing a network of these sensitive receivers can lead to a remarkably accurate assessment of plate movement.
There are two available radio signals that GPS receivers can use: the Standard Positioning Service (SPS) for civilians, and the Precise Positioning Service (PPS) for military and other authorized personnel. The most significant cause of errors in positioning is the deliberate effort by the Department of Defense to decrease the accuracy of user systems for national security reasons. Selective Availability (SA) refers to the purposeful degradation of the information broadcast by the satellites. SA affects the accuracy of the SPS, but not PPS. With SA, a GPS system will be accurate 95% of the time to within 328 feet (100 meters) horizontally and 512 feet (156 meters) vertically.
For those who require positions with higher accuracy, Differential Global Positioning Systems (DGPS) add a new element to GPS. DGPS places a GPS stationary receiver at a known location on or near the Earth's surface. This reference station receives satellite signals and adjusts for transmission delays and Selective Availability, using its own known latitude, longitude, and altitude. The stationary receiver sends out a correction message for any suitably-equipped local receiver. A DGPS-compatible receiver adjusts its position calculations using the correction message. DGPS reference stations are constructed, operated, and maintained by the United States Coast Guard.
Weather satellites have been our eyes in the sky for more than 30 years, since the April, 1960 launch of Tiros I. Today, satellite images showing the advance of weather fronts are regular elements of the evening news. This meteorological information is also available to anyone with a personal computer. A network of American, European, Japanese, and Russian satellites orbits the Earth in various configurations to provide "real-time" monitoring of our environment. Many of these satellites transmit signals directly to ground stations in schools, including the Frank H. Harrison Middle School in Yarmouth, Maine, and Wiscasset Primary School in Wiscasset, Maine. Highly-trained technicians, like Georgie Thompson's second-grade students, operate the controls of such a station. They are able to predict when the satellites will be overhead, when they can expect to receive an image, and they can loop together several images of cloud conditions and movements from different passes of the satellites to make reliable weather predictions. Any school can establish such a ground station at a surprisingly low cost.
TIROS polar orbiting satellites (NOAA-class), launched and operated by the United States, are the principal sources of environmental data for the 80% of the globe that is not covered by conventional monitoring equipment. These satellites measure temperature and humidity in the Earth's atmosphere, record surface ground and surface sea water temperatures, and monitor cloud cover and water/ice boundaries. They have the capability to receive, measure, process, and retransmit data from balloons, buoys, and remote automatic stations distributed around the globe. These satellites also carry Search and Rescue (SAR) transponders, which help locate downed airplanes or ships in distress. Polar orbiting satellites send back pictures to Earth via Automatic Picture Transmission (APT) or High Resolution Picture Transmission (HRPT) formats.
NOAA (National Oceanic and Atmospheric Administration) class satellites and Russian Meteor class satellites orbit very close to the poles on each revolution of the Earth. At an altitude of 860 km. (600 miles), the sensors scan the Earth's entire surface over a 24-hour period. The sensors are sensitive to visible light and infrared (IR) radiation. As each NOAA polar-orbiting satellite orbits the Earth, it sends back a constant stream of data.
Instruments on board the satellite scan the Earth's surface from side to side (perpendicular to the ground track), with each scan covering an area about 2 km. high and 3,000 km. wide. Typically, the lower resolution APT imagery is transmitted at 2 lines/second, or 120 lines/minute. In a pass lasting 12 minutes, this translates into an image approximately 5,800 km. long and 3,000 km. wide. As an example, the entire east coast of the United States would be visible in one image, from southern Florida north up to Hudson Bay, and from the Atlantic Ocean to west of the Great Lakes.
During the day, this data stream consists of one visible and one infrared image. At night, both channels are infrared. Imagery in both the visible and infrared formats is transmitted simultaneously. Students are familiar with the visible image because it is similar to one from a conventional camera. Understanding what the infrared imagery represents is sometimes harder to grasp. Various land and water bodies absorb heat differentially, so they reflect different levels of heat energy. The Gulf Stream offers an excellent example: on an infrared image, the warmer temperatures of the Gulf Stream are clearly delineated as the darker portions of the image, while the cooler temperatures of the surrounding Atlantic are lighter in color. With readily-available computer software, students can use a mouse to place a cursor anywhere on the image and accurately measure the surface water temperature to within 2 degrees Fahrenheit.
Currently, four NOAA-class satellites, which transmit both APT and HRPT imagery, are available for classroom use. NOAA 14 passes over Maine in the middle of the day. NOAA 12 is considered the primary early morning and early evening satellite. In addition to the United States' NOAA satellites, Russian Meteor class satellites transmit weather satellite imagery in the APT format as well. As a result, these satellites are also a valuable resource for your classroom.
In late 1966, ATS-1 was launched into a geostationary orbit over the equator south of Hawaii. For the first time, meteorologists could monitor the weather continuously during daylight. It provided images of nearly one-third of the Earth's surface every 23 minutes with 4 km. resolution.
In May of 1974, the first of a new series of GOES satellites was launched. Both visible and infrared images were acquired simultaneously by the Visible and Infrared Spin Scan Radiometer (VISSR) on board the spacecraft. The visible channel offers ground resolution of 0.8 km. for sections of the full Earth view and 6.2 km. resolution in the infrared spectra. The greatest advantage to having both visible and infrared capability is that weather systems can be monitored both day and night (at 30-minute intervals). Thus, destructive hurricanes can be tracked around the clock. Most satellite images seen on our local evening news and the Weather Channel are produced by GOES satellites. Usually, the infrared images are "loop animated" to show the progression and movement of storms.
While the United States maintains and operates its GOES satellites, the European community is served by its European Space Agency (ESA) Meteosat satellite, and Japan with its GMS satellite. This network provides complete global coverage of all but the extreme north and south polar regions.
GOES satellites make day and night observations of weather in the coverage area and transmit real-time VISSR data, monitor cataclysmic weather events such as hurricanes, relay meteorological observation data from surface collection points, and perform facsimile transmission of processed graphic and imaged weather data. This rebroadcast function is known as WEFAX, which stands for Weather Facsimile.
The primary function of our GOES satellites to the education community is to provide imagery of varying resolution and time frames. VISSR is the most stunning example, although it requires a much more sophisticated ground station to receive and process the signal. From Hawaii to Maine, land features can be examined to 0.8 km. resolution. The snow-capped Rocky Mountains stand out nicely, as do larger lakes and reservoirs.
WEFAX, on the other hand, is easily received with relatively simple equipment. Much of the imagery transmitted via WEFAX is considered low resolution, usually 4 km. Along with satellite imagery, weather charts and other information are also transmitted regularly.
Four Landsat satellites (launched in 1972, 1975, 1978, and 1982) were specifically designed to learn about how different parts of the planet interact. Three are still sending back data. The newest generation of environmental satellites is part of a National Aeronautics and Space Administration (NASA) initiative that aims its space instruments at the Earth instead of the stars.
This program, Mission to Planet Earth, may well take precedence over space exploration for the next few years. Its Earth Observing System (EOS) will include 17 new satellites to be launched over the next 15 years. "The idea grew out of a critical mass of scientists coming together to understand how the Earth as a system is changing," explains Robert Price, director of the Mission to Planet Earth office for NASA. "If humankind is changing the face of the Earth, it's time we started answering some of the scientific questions relating to that." EOS focuses on the remote sensing of climate change indicators such as the ozone layer in the upper atmosphere, cloud cover, and sea-ice at the poles. In addition, it follows the climatological effects of localized phenomena like volcanic eruptions and El Niño, a periodic change in wind patterns and current movements that results in decreased fisheries along the southern Pacific coast. The information provided by EOS satellites will determine the course of environmental management in the future.
The Topex/Poseidon project is a joint venture between NASA and the French Space Agency designed to study the dynamics of the ocean as part of Mission to Planet Earth. The satellites orbit 830 miles above the Earth and measure the height of sea level to within 5 inches. Using these measurements, scientists examine ocean circulation patterns and interactions between the ocean and the atmosphere in an effort to predict climate changes on a global level. Topex/Poseidon imagery helped scientists predict the 1994-1995 El Nino and its effects in the Northern Hemisphere.
The SeaWIFS satellite will provide important data on ocean productivity. SeaWIFS stands for the Sea-viewing Wide Field of View Sensor, designed to measure the amount of phytoplankton in the ocean and the seasonal changes in distribution. This satellite will also examine the fate of sediments washed from the land into the ocean and the mixing of nutrients at the edge of eddies and boundary currents. Measuring phytoplankton blooms from space has an obvious advantage over trying to cover the vast tracts of the ocean from a boat. The SeaWIFS satellite replaces an earlier sensor called the Coastal Zone Color Scanner (CZCS) that failed in the late 1980s.
The Space Transportation System (STS) followed the Apollo Project to the Moon and Skylab which orbited the Earth from 1973 to 1979. With the flight of the shuttle Columbia on April 12, 1981, America entered a new era in manned space flight. The reusable shuttle enables regularly-scheduled transportation for people and cargo between Earth and low Earth orbit, providing dramatic imagery of bold satellite rescue and repair missions. Less dramatic, but more personal, offshoots of this aerospace research include computer software in cars and airplanes and a host of medical technologies including CAT scans, portable x-ray machines, and laser surgery.
The current schedule of space shuttle missions provides an excellent opportunity for students and teachers to monitor flight activity on a real-time basis. Shuttle launch manifests offer approximate dates and durations of upcoming missions. A great deal of space-related information, including current shuttle manifests, is available at NASA's SpaceLink WWW page.
Schools with Amateur Radio ("ham") equipment or short-wave listening equipment can also monitor the audio portion of most shuttle missions. Station WA3NAN, located at the Goddard Space Flight Center in Greenbelt, Maryland, re-transmits live air-to-ground shuttle communications on amateur frequencies. The best times to monitor transmissions are during the launch and landing sequence and satellite deployment or repair missions.
In recent missions the Space Shuttle has carried a new type of radar called Spacebourne Imaging Radar - C/X - band Synthetic Aperature Radar (SIR-C/X-SAR). After launching, the cargo doors on the shuttle open to deploy this radar, which is designed to look at vegetation, soil moisture levels, ocean dynamics, volcanic activity, and erosion. The projects that have evolved using this data include studies of deforestation in the Amazon, desertification of the Sahara, and soil moisture retention in the Midwest.
In February of 1986, the then-Soviet Union launched a space platform called Mir (Russian for "peace") Space Station as a replacement for the aging SALYUT 7 space station. The Russians hold the world record for long-duration flight. In 1987, two cosmonauts spent more than 300 days in space and new records are set every year.
It is especially exciting to view the Mir Space station or to monitor its progress by radio because it is one of the few satellites manned almost continuously. Students may feel a connection with the people in the capsule when they can observe it speeding overhead. Mir was launched in a fairly high inclination orbit (51.6 degrees), so the orbit is directly over the most populated portions of the Earth. Using a simple pinwheel device, students can determine when and where to look for this and other space objects. One of the largest and brightest objects currently orbiting the Earth, this platform provides for spectacular viewing several times during a 5-6 week period. Mir traverses the sky with an apparent magnitude of 0 or +1. In comparison, the brightest stars or planets are usually of a magnitude of -1, and the faintest stars visible with the naked eye are in the range of +6, +7.
In preparation for the proposed International Space Station, seven dockings between the Space Shuttle and the Mir Space Station are planned between now and 1997. In June of 1995, the Shuttle Atlantis successfully docked with Mir and began the journey to the ultimate completion of the International Space Station by the year 2002.
Tracking Earth-orbiting satellites visually makes for a great outdoor homework assignment. Literally thousands of objects orbiting our planet are listed in the latest Satellite Situation Report compiled by NORAD (North American Air Defense), and distributed by NASA. Any satellite larger than a softball is tracked by NORAD, and the data is disseminated by NASA. Many of these are debris from payloads and rocket bodies, called "space junk." On any clear evening, you have an excellent chance to see a satellite about 1 to 1 1/2 hours after sunset. Most will be observed in north-south or south-north orbit. In the space of an hour or more, a dozen satellites can be spotted. Brightness of the objects will vary depending on orbital altitude, size, and spin rate. Although part of the Earth is in the sun's shadow at night, the satellite is still in sunlight, and the reflected sunlight illuminates it for Earth-bound observers.
How does one know when and where to look for specific satellites, such as the Soviet Mir Space Station, and, on occasion, even the US Space Shuttle? Amateurs have been tracking satellites for more than two decades. Before the microcomputer became a household item, ham radio operators plotted orbits on maps to determine when the satellites could be seen overhead. This method is still in use and is a good primer for those interested in tracking orbiting satellites.
In 1969, interested hams formed the Amateur Radio Satellite Corporation (AMSAT) to continue to enhance amateur satellite communication. Through the years, AMSAT has been a leader in research and development for amateur satellite technology. With the advent of microcomputers, tracking programs were written to automatically track specific satellites of interest, thus leaving the operator with more time to communicate.
How does the computer operator know which satellite is which? The user must input information for each satellite. These numerical data sets are called Keplerian Elements, named after Johannes Kepler. These elements, unique to each satellite, are orbital parameters which define individual orbits. They are available from a variety of sources on the Internet. Many of the newer tracking programs, including InstaTrack (PC) and OrbiTrak (Mac), provide users with quick means of updating elements. Complete files can be downloaded in a matter of minutes, and the computer software updates elements for as many as 200 satellites in seconds. Compare this with the arduous task of updating each satellite via computer keyboard, which takes several minutes per satellite. Either way, information is available for all satellites of interest to educators, including weather satellites, amateur satellites, and objects of high visibility such as the Mir space station. It is important to secure the latest Keplerian element sets available when tracking the Russian Mir Space Station or the Space Shuttle.
The satellite UOSAT-11 is one of dozens of amateur satellites orbiting the earth. Sputnik, the world's first artificial Earth-orbiting satellite, transmitted a beacon on 20.005 MHz. which was monitored by thousands of hams and Short Wave Listeners (SWL). Since 1957, many OSCAR (Orbiting Satellites Carrying Amateur Radio) satellites have been constructed by ordinary people interested in satellite communications. Oscar 1, launched in December of 1961, weighed 10 pounds and transmitted a 15 milliwatt beacon for about 3 weeks. Oscar 13, launched in the summer of 1988, provides reliable, near-global communications. Interestingly enough, the OSCAR series of satellites are actually ballast for larger primary NASA payloads. It is simpler and cheaper to ballast a rocket with dead weight than to reduce the thrust. As a result, it is possible to add secondary payloads of homemade satellites to multimillion-dollar NASA missions at minimal costs.
There are currently nineteen OSCAR satellites orbiting our planet with various communications capabilities and functions. Most are used by ordinary amateur radio operators for educational, scientific, and purely recreational purposes. Anyone interested in knowing more about the OSCAR series of satellites is encouraged to contact the Amateur Radio Satellite Corporation (AMSAT).
or directly to the subsections below:
Comparing Oceans | Human Impact | Antarctica | Weather
How Satellites Work | Remote Sensing | Imaging the Earth
Gulf of Maine Aquarium Home Page
To make navigation through our WWW pages easier, we have included several alternate starting points:
Last modified 12/08/2005 23:31:09
Copyright (c) 2000. Gulf of Maine Aquarium.
All rights reserved. Mail comments to firstname.lastname@example.org
October 16, 2010 Category : Miscellaneous
Engineering is the discipline, art and profession of acquiring and applying scientific, mathematical, economic, social, and practical knowledge to design and build structures, machines, devices, systems, materials and processes that safely realize solutions to the needs of society.
The American Engineers' Council for Professional Development (ECPD, the predecessor of ABET) has defined "engineering" as:
[T]he creative application of scientific principles to design or develop structures, machines, apparatus, or manufacturing processes, or works utilizing them singly or in combination; or to construct or operate the same with full cognizance of their design; or to forecast their behavior under specific operating conditions; all as respects an intended function, economics of operation and safety to life and property.
One who practices engineering is called an engineer, and those licensed to do so may have more formal designations such as Professional Engineer, Chartered Engineer, Incorporated Engineer, or European Engineer. The broad discipline of engineering encompasses a range of more specialized subdisciplines, each with a more specific emphasis on certain fields of application and particular areas of technology.
The concept of engineering has existed since ancient times as humans devised fundamental inventions such as the pulley, lever, and wheel. Each of these inventions is consistent with the modern definition of engineering, exploiting basic mechanical principles to develop useful tools and objects.
The term engineering itself has a much more recent etymology, deriving from the word engineer, which itself dates back to 1325, when an engine’er (literally, one who operates an engine) originally referred to “a constructor of military engines.” In this context, now obsolete, an “engine” referred to a military machine, i.e., a mechanical contraption used in war (for example, a catapult). Notable exceptions of the obsolete usage which have survived to the present day are military engineering corps, e.g., the U.S. Army Corps of Engineers.
Later, as the design of civilian structures such as bridges and buildings matured as a technical discipline, the term civil engineering entered the lexicon as a way to distinguish between those specializing in the construction of such non-military projects and those involved in the older discipline of military engineering.
 Ancient era
The Pharos of Alexandria, the pyramids in Egypt, the Hanging Gardens of Babylon, the Acropolis and the Parthenon in Greece, the Roman aqueducts, Via Appia and the Colosseum, Teotihuacán and the cities and pyramids of the Mayan, Inca and Aztec Empires, the Great Wall of China, among many others, stand as a testament to the ingenuity and skill of the ancient civil and military engineers.
The earliest civil engineer known by name is Imhotep. As one of the officials of the Pharaoh, Djosèr, he probably designed and supervised the construction of the Pyramid of Djoser (the Step Pyramid) at Saqqara in Egypt around 2630-2611 BC. He may also have been responsible for the first known use of columns in architecture.
Ancient Greece developed machines in both the civilian and military domains. The Antikythera mechanism, the first known mechanical computer, and the mechanical inventions of Archimedes are examples of early mechanical engineering. Some of Archimedes' inventions as well as the Antikythera mechanism required sophisticated knowledge of differential gearing or epicyclic gearing, two key principles in machine theory that helped design the gear trains of the Industrial revolution, and are still widely used today in diverse fields such as robotics and automotive engineering.
Chinese, Greek and Roman armies employed complex military machines and inventions such as artillery which was developed by the Greeks around the 4th century B.C., the trireme, the ballista and the catapult. In the Middle Ages, the Trebuchet was developed.
 Renaissance era
The first steam engine was built in 1698 by mechanical engineer Thomas Savery. The development of this device gave rise to the industrial revolution in the coming decades, allowing for the beginnings of mass production.
With the rise of engineering as a profession in the eighteenth century, the term became more narrowly applied to fields in which mathematics and science were applied to these ends. Similarly, in addition to military and civil engineering the fields then known as the mechanic arts became incorporated into engineering.
 Modern era
Electrical engineering can trace its origins in the experiments of Alessandro Volta in the 1800s, the experiments of Michael Faraday, Georg Ohm and others and the invention of the electric motor in 1872. The work of James Maxwell and Heinrich Hertz in the late 19th century gave rise to the field of Electronics. The later inventions of the vacuum tube and the transistor further accelerated the development of electronics to such an extent that electrical and electronics engineers currently outnumber their colleagues of any other Engineering specialty.
The inventions of Thomas Savery and the Scottish engineer James Watt gave rise to modern Mechanical Engineering. The development of specialized machines and their maintenance tools during the industrial revolution led to the rapid growth of Mechanical Engineering both in its birthplace Britain and abroad.
Chemical Engineering, like its counterpart Mechanical Engineering, developed in the nineteenth century during the Industrial Revolution. Industrial scale manufacturing demanded new materials and new processes and by 1880 the need for large scale production of chemicals was such that a new industry was created, dedicated to the development and large scale manufacturing of chemicals in new industrial plants. The role of the chemical engineer was the design of these chemical plants and processes.
Aeronautical Engineering deals with aircraft design while Aerospace Engineering is a more modern term that expands the reach envelope of the discipline by including spacecraft design. Its origins can be traced back to the aviation pioneers around the turn of the century from the 19th century to the 20th although the work of Sir George Cayley has recently been dated as being from the last decade of the 18th century. Early knowledge of aeronautical engineering was largely empirical with some concepts and skills imported from other branches of engineering.
The first PhD in engineering (technically, applied science and engineering) awarded in the United States went to Willard Gibbs at Yale University in 1863; it was also the second PhD awarded in science in the U.S.
Only a decade after the successful flights by the Wright brothers, the 1920s saw extensive development of aeronautical engineering through development of World War I military aircraft. Meanwhile, research to provide fundamental background science continued by combining theoretical physics with experiments.
 Main branches of engineering
Engineering, much like other science, is a broad discipline which is often broken down into several sub-disciplines. These disciplines concern themselves with differing areas of engineering work. Although initially an engineer will usually be trained in a specific discipline, throughout an engineer's career the engineer may become multi-disciplined, having worked in several of the outlined areas. Historically the main Branches of Engineering are categorized as follows:
- Aerospace engineering - The design of aircraft, spacecraft and related topics.
- Chemical engineering - The exploitation of chemical principles in order to carry out large scale chemical process, as well as designing new specialty materials and fuels.
- Civil engineering - The design and construction of public and private works, such as infrastructure (roads, railways, water supply and treatment etc.), bridges and buildings.
- Electrical engineering - a very broad area that may encompass the design and study of various electrical & electronic systems, such as electrical circuits, generators, motors, electromagnetic/electromechanical devices, electronic devices, electronic circuits, optical fibers, optoelectronic devices, computer systems, telecommunications and electronics.
- Mechanical engineering - The design of physical or mechanical systems, such as engines, compressors, powertrains, kinematic chains, vacuum technology, and vibration isolation equipment.
New specialties sometimes combine with the traditional fields and form new branches. A new or emerging area of application will commonly be defined temporarily as a permutation or subset of existing disciplines; there is often gray area as to when a given sub-field becomes large and/or prominent enough to warrant classification as a new "branch." One key indicator of such emergence is when major universities start establishing departments and programs in the new field.
For each of these fields there exists considerable overlap, especially in the areas of the application of sciences to their disciplines such as physics, chemistry and mathematics.
Engineers apply the sciences of physics and mathematics to find suitable solutions to problems or to make improvements to the status quo. More than ever, engineers are now required to have knowledge of relevant sciences for their design projects, as a result, they keep on learning new material throughout their career.
If multiple options exist, engineers weigh different design choices on their merits and choose the solution that best matches the requirements. The crucial and unique task of the engineer is to identify, understand, and interpret the constraints on a design in order to produce a successful result. It is usually not enough to build a technically successful product; it must also meet further requirements.
Constraints may include available resources, physical, imaginative or technical limitations, flexibility for future modifications and additions, and other factors, such as requirements for cost, safety, marketability, productibility, and serviceability. By understanding the constraints, engineers derive specifications for the limits within which a viable object or system may be produced and operated.
 Problem solving
Engineers use their knowledge of science, mathematics, logic, and appropriate experience to find suitable solutions to a problem. Engineering is considered a branch of applied mathematics and science. Creating an appropriate mathematical model of a problem allows them to analyze it (sometimes definitively), and to test potential solutions.
Usually multiple reasonable solutions exist, so engineers must evaluate the different design choices on their merits and choose the solution that best meets their requirements. Genrich Altshuller, after gathering statistics on a large number of patents, suggested that compromises are at the heart of "low-level" engineering designs, while at a higher level the best design is one which eliminates the core contradiction causing the problem.
Engineers typically attempt to predict how well their designs will perform to their specifications prior to full-scale production. They use, among other things: prototypes, scale models, simulations, destructive tests, nondestructive tests, and stress tests. Testing ensures that products will perform as expected.
Engineers as professionals take seriously their responsibility to produce designs that will perform as expected and will not cause unintended harm to the public at large. Engineers typically include a factor of safety in their designs to reduce the risk of unexpected failure. However, the greater the safety factor, the less efficient the design may be.
The study of failed products is known as forensic engineering, and can help the product designer in evaluating his or her design in the light of real conditions. The discipline is of greatest value after disasters, such as bridge collapses, when careful analysis is needed to establish the cause or causes of the failure.
 Computer use
As with all modern scientific and technological endeavors, computers and software play an increasingly important role. As well as the typical business application software there are a number of computer aided applications (Computer-aided technologies) specifically for engineering. Computers can be used to generate models of fundamental physical processes, which can be solved using numerical methods.
One of the most widely used tools in the profession is computer-aided design (CAD) software which enables engineers to create 3D models, 2D drawings, and schematics of their designs. CAD together with Digital mockup (DMU) and CAE software such as finite element method analysis or analytic element method allows engineers to create models of designs that can be analyzed without having to make expensive and time-consuming physical prototypes.
These allow products and components to be checked for flaws; assess fit and assembly; study ergonomics; and to analyze static and dynamic characteristics of systems such as stresses, temperatures, electromagnetic emissions, electrical currents and voltages, digital logic levels, fluid flows, and kinematics. Access and distribution of all this information is generally organized with the use of Product Data Management software.
There are also many tools to support specific engineering tasks such as Computer-aided manufacture (CAM) software to generate CNC machining instructions; Manufacturing Process Management software for production engineering; EDA for printed circuit board (PCB) and circuit schematics for electronic engineers; MRO applications for maintenance management; and AEC software for civil engineering.
In recent years the use of computer software to aid the development of goods has collectively come to be known as Product Lifecycle Management (PLM).
October 16, 2010 Category : Miscellaneous
The modern age is the age of science. The inventions of science govern our life. At every stage we are dependent on the inventions and discoveries of science.
In the every day life of an individual science plays a very important and significant part. The discoveries of science such as electricity, wireless, telephone, railways, airplanes, medicines, etc. are extremely valuable and it is difficult to conceive of modern life without the amenities provided by modern science. We are really very grateful to scientists who have rendered great services to humanity by their manifold discoveries.
Scientific inventions and discoveries are used without conscience, and the result tit that modern scientific inventions are dragging humanity on the path of destruction and ruin. if the scientific inventions are sued with conscience i.e. with the full realization of the destruction and ruin that will be brought about by the indiscriminate sue of the weapons of science, there will be no danger to humanity. But when scientific inventions are used without conscience they are likely to send the humanity to its doom. Hence what is urgently needed is that the scientists should employ their scientific inventions with caution and care so that mankind may not have to suffer as a result of the indiscriminate use of scientific discoveries.
Atom is a vast source of energy and if it is employed with conscience for the service of humanity it can be a source of welfare to mankind. But unfortunately atomic energy is being harnessed without conscience for destructive purposes. Bombs are being made out of this potential energy. The atom bomb was the outcome of the craze of scientists to use atomic energy for destructive purposes. it was used by the Americans in Second world War of 1939-1945 and the two cities of Japan, Hiroshima and Nagasaki, had suffered incalculable losses in men and money due to the conscienceless employment of atomic energy in warfare.
It is an admitted fact that scientific inventions, particularly the inventions used in modern warfare, have been employed without conscience in the past and will be employed without conscience in the future unless we go to the root of conscienceless use of scientific weapons and seek to cut t the very root of this wrong basis. The main reasons why scientific inventions are used root of this wrong basis. The main reason why scientific inventions are used in a conscienceless manner is that nations using them are cut of expansion and aggrandizement at the cost of weaker nations. The lust of territorial expansion and subjugations of weaker powers is the root of this wrong and immortal employment of scientific weapons of warfare. So long as nations will vie with one another in territorial supremacy, and expansion of their sphere of influence, scientific weapons will continue to be employed in a conscienceless and unscrupulous manner by modern warriors.
Another reason for this wrong and unethical use of scientific weapons is a greed and jealousy of big power, who cannot see eye to eye with each-other on international problems, and who have ideological differences dividing them is separable groups. It is this rivalry, strife and hatred that leads warring nations to use fair or foul methods for subjugating and crushing their foes in the war. There are other reasons equally powerful such as ambition for world domination, control of scientific weapons, which lead belligerent nations to the use of scientific weapons in an abashed and immoral way.
If we really want that scenic inventions may not be used unscrupulously and conscienceless to the determent of humanity, it will be necessary to bring about a basis change in the mental attitude of the great powers who are likely to be embroiled in a global war. Great nations should realize that war is not the civilized way of settling international disputes. War is a relic of barbarism and an expression of the instinct of pugnacity rooted in man in a crude form. In civilized society the belligerent instinct can be modified, and peaceful methods can be employed for the settlement of disputes and disagreements among nations. War would be banned as a means of arriving at solutions of vexing international problems. Only then there is the possibility that scientific inventions will not be harnessed to gain wrong ends, and the brains of the scientists will be used in making discoveries which will ensure the steady progress of civilization. And if war can not be outlawed then at least there should eb a ban on the use of nuclear weapons such as atom bomb and hydrogen bomb in the future worlds. this ban will also provided a check to the conscienceless use of weapons in modern war.
We should learn to use the marvels of science for the welfare of humanity and the progress of our civilization. "The need of mankind" observed Rd. Rajendra Prasad, the Late President of India, "if it is to survive, is to hark back to the supremacy of the moral law and to take the path of self-conquest. Without taking a moral view of life, we cannot properly use the inventions of science for the welfare of humanity. Science grounded in spirituality and not in materialism can alone bring about the salvation of the human-race".