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| SCIENCE TRIBUNE | Thursday, January 6, 2000, Chandigarh, India |
4 satellites to study sun by Radhakrishna Rao SUN the throbbing source of inexhaustible energy, has always fascinated and captivated man. As a sustainer of life on earth, sun has for long remained a focus of an intensive scientific investigation. Despite the close-up study of sun using satellite probes and ground based observation, many of the features and phenomenon of the sun continues to remain a scientific riddle. Art of alcoholic
beverages making Ultimate
death rays
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4 satellites to study sun SUN the throbbing source of inexhaustible energy, has always fascinated and captivated man. As a sustainer of life on earth, sun has for long remained a focus of an intensive scientific investigation. Despite the close-up study of sun using satellite probes and ground based observation, many of the features and phenomenon of the sun continues to remain a scientific riddle. In order to gain a better understanding into the influence of the sun on our planet’s environment, the 14-nation European Space Agency (ESA) has unveiled Cluster-II mission comprising as many as four satellites — flying information between 19,000 kg and 119,000 km above the earth. The four spacecraft mission will be launched in mid-2000 by means of the Russian Soyuz rocket from the Baikonur cosmodrome in Kazakstan. Cluster-II is a part of an international programme to find out more about how the sun exerts impact on earth’s environment. The four Cluster-II satellites will join an armada of spacecraft from many countries, which are already studying the sun and high speed wind of charged particles (mainly electrons and protons) which it continually blasts into space. Ulysses and SOHO, both joint European-American missions and ESA’s cluster-II, when it will be there, are the flagships of this armada. The timing of the mission is ideal, since it will take place during a period of peak activity in the sun is eleven-year cycle, when sunspots and solar radiation reach a maximum. Cluster-II will measure the effects of this activity on near-earth space as incoming energetic particles subject the magnetosphere—the region dominated by the earth’s magnetic field—to a buffeting. Each of the Cluster-II spacecraft carries an identical set of 11 instruments provided by the scientific institutions in different countries. Significantly, Cluster-II will be the first space mission ever to fly four identical spacecraft simultaneously. Once the quartet has been inserted into highly elliptical polar orbits, ranging from 19,000 to 119,000 km above the earth, they will spend the next two years travelling from the magnetosphere into interplanetary space and back again. Sometime, they will be within a few hundred kilometres of each other, sometimes 20,000 km apart, depending on the physical phenomenon to be studied. By orbiting in a tetrahedral (triangular pyramid) formation, they will be able to make the first detailed three dimensional study of the changes and processes taking place in near-earth space. As the satellites orbit the earth, they will investigate the rapid changes which occur in the earth’s atmosphere when large number of electrically charged particles in the solar wind reach the earth. Huge amounts of data will be returned which will help scientists unravel the physical process and small-scale variations taking place in the near-earth environment. “Cluster-II will give us the best information yet on how the sun affects the near-earth environment”, says Cluster-II project scientist Philippe Escouber. “For the first time we will be able to study the earth’s magnetic field from four viewpoints with identical instruments. “It will be like having four cameras at a football match-one behind the goal and three others at different angles” says he. Solar researchers say that such studies are not just of academic interest, for the sun affects our world in many ways. Apart from its familiar output of light, heat and ultraviolet radiation, our nearest star also emits a continuous stream of atomic particles — the solar wind — that sweeps out into space at speeds ranging from 280 to 1000 kms. Sometimes explosions on the sun send millions of tonnes of gas towards the earth. These clouds of high energy particles can travel the 150-million km between the sun and earth in a few days. The most energetic particles of all, created by solar flares, can reach the earth in just 30 minutes. This activity is particularly noticeable at times of solar maximum. When charged particles from the sun enter the earth’s upper atmosphere, they create shimmering curtains of coloured light, known as auroras, in the polar night sky. Other effects of sun on earth’s environment include.
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Art of alcoholic beverages
making Alcoholic beverages are common drinks of the rich and poor from time immemorial. They are being consumed worldwide, in both underdeveloped and developed countries. Their consumption produces deleterious effects on human system when taken in appreciable doses. The common alcoholic beverages are derived from plants like barley, grapes, rye, rice, maize, wheat, banana, sugarcane, cassava, sweet potato, yucca, sorghum, pineapple, cashew nut, palm, apple etc. Alcoholic beverages are produced using different strains of yeasts, such as Saccharomyces cerevisiae, S. ellipsoideus and S. carlsbergenesis, which convert sugars (such as glucose, maltose etc.) into ethanol or alcohol and CO2. These sugars obtained from fermentable substrates i.e. utilisable carbohydrates called must can be used directly to allow natural fermentation to occur or after sterilisation by means of pasteurisation or by treating it with SO2 (to inhibit growth of wild yeast) followed by addition of desired strains of the yeast species. Complex carbohydrates must be degraded/hydrolysed by enzymes (produced by barley malts or moulds) or acid. Wine is generally made from grapes and rice. The various steps involved in wine production are collection of grapes followed by crushing and separation of the must prior to fermentation and concludes with a variety of storage and ageing (varying between 1-15 years) steps for clearing and development of flavour. Clearing or racking (removal of sediments produced during fermentation) can be carried out at the time the fermented wine is transferred to bottles or casks (charred oak barrels) for ageing or even after the wine is transferred in bottles. All grapes have white juices. Red wine is prepared from red grapes without removing skins to release their coloured components. The must are fermented for 3-5 days (temp 20-28°C) and the final product may contain 10-18% alcohol. Dry (no free sugar) or a sweeter (with varying amount of free sugar) Wine can be made by controlling the level of the initial must sugar concentration. Grapes usually need no additional sugars but other fruits are to be supplemented with sugars to ensure enough alcohol production. Sometimes, bacteria that can convert the malic acid to lactic acid by a process called “malolactic fermentation” are added for the production of better tasting wine. “Burned wine” or “Brandy” is made by distilling wine where alcohol concentration is increased to 40-45%. Exposure of wine to air i.e. deliberately allowing the growth of aerobic bacteria belonging to genera Acetobacter or Gluconobacter by maintaining temperature between 15-35 °C can convert it into acetic acid or vinegar. Thus, alcohol is produced using yeasts by anaerobic fermentation of carbohydrates which can aerobically oxidised to acetic acid. “Sake”, the Japanese rice wine, is made from rice without malting (i.e. germination of grains and activation of their enzymes) because the mould Aspergillus oryzae is first used to convert complex carbohydrates in rice into simple sugars followed by incubation at 20 °C with the addition of desired strains of yeast by which 14-16% alcohol is produced. Champagnes are produced by carrying secondary fermentation in the inverted bottles (having 2.5% sugars and yeast) incubated at 15 °C which produce CO2 and yeast settles quickly. The neck of the bottles is frozen and the cork removed to disgorge the accumulated sediments and the bottles are refilled with clear, sparkling champagne from another disgorged bottle. Bourbon is an example of whiskey prepared from rye and maize. Scotch whiskey is made primarily of barley. Sometimes, mash is inoculated with a homolactic organism such as Lactobacillus sp. for lowering mash pH to near 3.8 for preventing growth of undesirable micro-organisms. Secondary distillation is carried to convert sugar to 50-95% alcohol as also for making RUM from cane molasses followed by ageing in charred oak barrels. Vodka (a Russian alcoholic drink from rye and other vegetable products) is also produced by distillation. Gin (colourless alcoholic drink) is vodka to which often Juniper berries are added for providing aroma and flavour. In the case of beer and ale production, after malting (from barley, wheat, rye etc.) the mash is heated with hops (dried flowers of the female vine, Humulus lupulis) which provide flavour and assist in the clarification followed by inoculation with desired strains of the yeast (S. carlsbergenesis, a bottom yeast, settle at the bottom of the fermentation vessel at 37-50 °C, pH 4.1-4.2, 7-12 days) for beer (4% alcohol) and S. cerevisiae (top yeast, grows at the top at 50-70 °C, pH 3.8) to produce ale (6% alcohol). Flavour is also influenced by the production of small amount of glycerol and acetic acid and addition of CO2. Beer is then pasteurised at 140°F or sterilised by passing through membrane filter to minimise flavour changes. Spirits are produced from beer, where the fermented liquid is boiled and the volatile components are condensed to yield a product with a higher alcohol concentration than beer. Thus, much of the art of alcoholic beverage making involves the controlled hydrolysis of protein and carbohydrates and other steps to provide the desired body and flavour of the final product. The writers are
from Deptt of Biosciences, H.P. University, Shimla. |
Ultimate death rays IN 1960 the first laser was demonstrated and death rays became “respectable.” Though it was hard to believe that they could ever produce death dealing power. The Laser (Light Amplification by Stimulated Emission of Radiation) arm race is producing more and more destructive beams. Though many modes of producing lasers have been tried but CO2 lasers now lead the field in laser weaponry.They produce infrared lasers (here ‘1’ stands for light) which are really “horrifyingly powerful”. Though all such lasers are most efficient in vacuum of space as the air on earth soaks their power and scatters them, yet experiments prove that a large laser can destroy a small antitank missile from a distance of 1 km. In other top secret experiments lasers have been fired at aircraft. A British study in 1981 predicted that a ground based anti-aircraft laser would be in routine use by 1995 or so. It is understood that satellites are also being used for military purposes. For example they are regularly launched by Russia and America to spy on each other. Spy satellites have powerful cameras that can photograph vehicles and even people on ground. It is almost certain that if Third World War occurs the “Quick and sure” artificially intelligent laser weapons will take care of ground and aerial attacks by enemy (whereas ICBMs with nuclear warheads will look after the distant targets). Who knows some of the satellites above our head might be carrying laser devices, but for the time being they would not be able to fire from space to ground. They can only destroy other satellites in their field of vision. They would also disable the long range missiles-which come out of the atmosphere in peak of their flight path. This would just be an orbital fighting, but of course with dire consequences. It’s so simple you just switch off the enemy’s satellite in orbit and watch them going blind and paralysed (as today’s infantry, navy or airforce is very much dependent on satellites). It will be cheap on the part of attacking nation but too costly for the victim country. But as the advancement of laser weapons takes place so will be of the defensive methods. We know that laser beam is basically a beam of light and follows all laws of reflection and refraction. It means if anybody shoots you with a laser gun you just show him a mirror, and so you don’t have to bear cost of buying a laser gun for yourself to teach him a lesson. Another more clever choice is to develop some system for satellites so that it can “eat and digest” the laser beam. The energy in the form of laser beam which is “thrown” at your satellite will be absorbed and used up for its own benefits. (Here you save the cost of mirror too!) But lasers need not be
restricted to low energy radiation eg: Infrared or
visible light. An X-ray laser (raser-here ‘r’
stands for Roengten) pumped by the nuclear explosion has
already been tested. As soon as they are declared OK for
routine use the “ultimate death rays” will soon
follow. These are gamma-ray lasers (graser-here
‘g’ stands for gamma), the photons of which are
millions of time more energetic than infrared photons of
today’s biggest laser. Our technology today lacks
the controlled power to pump a graser. But when it is
done, these will be true planet Smasher beams. Most
possibly there would be no defensive measures, against
it. You have to simply remember your god and welcome the
death. Some scientists and astronomers (who feel the
search of extraterrestrials worthless) believe it could
be the same story that might have happened with alien
civilisations out somewhere in the universe that they had
developed their technology to such an advanced level that
they had blown away their own planet (who otherwise had
the capacity to establish contacts with earth). For
example-a few billion megawatts of graser power could
blow up our sun or make stars go Nova at many light years
range. We should keep ourselves away from evils of
technology, and it will definitely be the most valuable
gift the science can give to mankind. |
Science Quiz 1. Name the US computer engineer who produced operating systems and application programmes which became the world standard for computers and brought to this business executive fame and fortune. 2. XMM is a satellite observatory designed to conduct research about the origin and future of our universe and is expected to operate for 10 years. What does XMM stand for? Which organisation has built this huge scientific instruments? 3. This white compound occurs naturally in marble, chalk, limestone etc. and is used in the manufacture of cement, iron, steel and lime. Which chemical are we talking about? 4. What is general about gravitational, electromagnetic, weak nuclear and strong nuclear forces? Name the theory that seeks to unite the properties of these forces. 5. What is the name of the device which is used to maintain constant speed in some contrivances (for example, a fuel regulator which automatically decreases the fuel supply when the engine exceeds a certain speed)? 6. If you were a student of “ichthyology”, what would you be studying and researching about? 7. The amount of unsaturated fatty acid present in a sample of fat, oil or any such product is measured by finding the percentage of iodine by weight absorbed by the sample in a given time under standard conditions. What is this measure called? 8. In anatomy, a node is a thickening or enlargement of an organ or tissue. In botany, a node is the position on the stem of a plant from which a leaf or leaves grow. What is a node in physics? 9. Some persons suffer from imagined diseases like stomach ache, headache, dizziness etc, although there is no such physical problem with the body. What is this mental condition of the patient called? 10. Named after a famous ornithologist of India, this institute is actively engaged in conducting studies and research about birds and related areas. Can you name this institute? Answers 1. Bill Gates 2. X-Ray
Multimirror Mission; European Space Agency 3. Calcium
carbonate 4. These are four fundamental or basic forces
of nature; Unified Field Theory 5. Governor 6. Fish 7.
Iodine value 8. A point of minimum displacement on a
stationary (standing) wave 9. Hypochondriasis 10. Salim
Ali Centre for Ornithology and Natural Science,
Coimbatore. |
