SCIENCE TRIBUNE | Thursday, August 23, 2001, Chandigarh, India |
Birth of
stars
SCIENCE
QUIZ |
Computers
that you can wear Wearable computers have been the dream of most science fiction films and TV series for many a year. But not any longer, according to the Japanese company NEC, one of the world leaders in computers, communications and electron devices. From its futuristic Advanced PC design centre in Tokyo, a handful of special engineers and designers have been busy creating what they envision as the future of personal computers, a wearable computer terminal. The wearable PC terminal is predicted to become an indispensable business tool, as well as a fashion accessory. Some of the models under development include; a wearable data terminal, a Lapbody computer, a TLC PC, a Porto Office and a Spoon PC. According to researchers the age is soon coming upon us when we will be wearing personal computers the way we wear clothes today. The NEC Corporation’s Tokyo design centre has made prototypes of a number of lightweight computers which can be worn on the human body. Some can be worn round the neck like a tie, others strapped round the waist like a belt, some slung from the shoulders and adorning the arms and legs. But these computers would be far from just adornments. They would make work easier and a user would no longer have the need to carry heavy laptops and notebooks. Memos could then be dictated while travelling, or simply utilising the time while having a cup of coffee. Computations could be done while relaxing at home with a drink or even on the golf course. But there would be more serious use of such personal wearable computers. They would greatly enhance the quality of medical services with the doctor always being just the press-of-button away. He may be sitting miles away, but all he has to do is to get the data of a patient and then communicate back his remedy, all through these computers. According to experts, in just a decade from now, computer miniaturisation would be so advanced that that it would allow computers to instantly recognise sounds and handwriting over long distances. These sophisticated computers would also incorporate miniature keyboards, voice mail facilities, telephones, faxes, CD roms and even cameras and satellite transmission. Weighing no more than a kilo each, these wonder computers would be made of very soft though superstrong plastic and would be strapped around the body with the help of velcro. They would come in various shapes and colours — perhaps to match the clothing of the wearer. However, the basic shapes of these computers designed at the Tokyo workshop are designed for specific tasks and they would be most beneficial for those people who do these special kind of work. For example, a Lapbody computer would be strapped around the arm and the keyboard and monitor would come at the bottom of the ribcage for easy accessibility. This contraption could be of special use to journalists and those who have to transmit field data apart from those with basic computing needs. However, the TLC computer would be specific to the needs of a doctor. Specific, because this would incorporate a body sensor for immediate response, a video camera to transmit pictures of a patient, a phone for messages and also a CD roms medical encyclopedia for quick reference. The Inventory Data Terminal, as the name suggests, would come in very handy for those working in large departmental stores. Strapped to a salesperson’s arm it would transmit data at the flick of a button on inventory, prices of items, sales figures and reading of bar codes. The Portable Office computer, of course, would encompass most of the functionings of a modern-day paperless office. Besides normal features like a monitor, keyboard and a printer, it would incorporate a phone, a fax machine, a CD rom and E-mail facilities. This would be a boon to people on the move. Most of these portable computers can be easily strapped and unstrapped. While resting or sitting they can be taken off and stood up on a stand for easy use. Indeed, at these personal wearable
computers would have the potential of revolutionising the world around
us. Even if a person is travelling or vacationing or just dining out,
he or she doesn’t need to lug a laptop or a notebook along. A busy
executive now just needs a contraption which can be worn like an
ornament with a small display screen. All that’s required to carry
the world in your pocket! NF |
Birth
of stars
To a casual observer, the night sky presents an unchanging look of star-studded hemispherical bowl. But careful observation of the milky way region on a clear night can reveal many patches with a relatively sparse population of stars. Presence of huge clouds of interstellar dust in these regions is responsible for this phenomenon. Dust blocks the view of background stars and so, only a few stars located in foreground of the cloud are visible. The presence of background stars is confirmed by making observations in the infrared and radio regions of the spectrum. American astronomer Bart J. Bok was the first person to study these clouds in the galaxy. According, these objects are popularly known as "Bok Globules". Scientists have discovered many of them using long-exposure photography. These clouds are the local concentrations of extremely tenuous interstellar dust and gas, which is spread over the entire galactic disk. Although the average density of this matter is of the order of one particle per cubic centimetre, over a span of millions of years, the weak gravitational attraction is able to unite them into huge clouds-thousands of times more massive than the sun. In the presence of a hot star, these clouds may reveal their presence by emitting extremely feeble pink radiation corresponding to Balmer alpha line of hydrogen. Once the cloud becomes heavy, it has a tendency to contract rapidly. But the resulting high temperatures provide sufficient buoyancy to prevent a rapid collapse. Accordingly, contraction can proceed just in proportion to the amount of energy lost as radiation. Since the cooling is more among outer layers, the whole mass becomes unstable and undergoes fragmentation into thousands of smaller clouds, each weighing almost as much as our sun. This results into many thousand nuclei of dense regions of dust and gas. As these individual clouds continue their journey of collapse, the gravitational force begins to occupy a dominant position, resulting into a progressive increase in temperature at the core. This hot cloud with a temperature of some 10 million degrees at its core is termed as "protostar". Protostar phase marks the end of gravitational collapse and the beginning of thermonuclear (fusion) reactions in the core, which put the star into its normal life cycle. Once the stars are born in this fashion, their strong ultraviolet radiation ionises the surrounding hydrogen gas, which starts emitting strong red light (Balmer Alpha line). In due course, the radiation pressure pushes away this shell of gas, revealing the newly born stars lying in their cradle. Rosette Nebula in Monoceros is an excellent example of this kind, where the new born stars belonging to open cluster NGC 2244 are blowing away the surrounding hydrogen gas and dust particles. The cavity thus created is several parsecs across. NGC 2244 is naked eye object (mag. 4.8) visible during winter season. Using a telescope, one can see the surrounding gas cloud. In a galaxy like ours, there are many
other factors that affect the gravitational collapse of the
interstellar dust cloud. The central bulge is populated by old stars,
many of whom end their lives through massive explosions, sending shock
waves through the outer disk. The wave fronts become the regions of
increased density and act like nuclei for the condensation of
interstellar matter into stars. Accordingly, we see many young star
clusters and associated nebulae along the spiral arms of our galaxy. |
SCIENCE
QUIZ 1. This Russia-born scientist discovered in Britain the bacteria needed for the production of acetone on a large scale, which also led to the production of butyl alcohol. Name this founder of the fermentation industry who was also instrumental in the creation of Israel and became its first President. 2. The underlying working of this 3,000-year old therapeutic Chinese technique has eluded scientists for long. Now scientists have obtained deeper insight into how this technique works. They have found that this technique eases blood pressure by stimulating specific receptors in the central nervous system, which can regulate neuronal activity in the brain. Which is this technique that, scientists hope, may help treat heart disease and other disorders? 3. What is the most common characteristic of the trees/plants "amaltas", "bougainvillaea", "gulmohar", "Chandani" and "hibiscus"? 4. This "lesser" and very uncommon cat resembles a jungle cat. Its distinguishing features are its uniform ochre-camel colour, black, large and pointed ears and long slender legs. It mainly feeds on hares, peafowls, partridges, desert gerbils, young ones of chinkaras, etc. Which is this exquisite creature that is one of the most endangered animals not only in India but in Asia as well? 5. What distinguishes a supersonic aircraft from a general aircraft from the point of view of physics? When a supersonic aircraft travels through air, it produces a sound bang. What is this bang called? 6. Polymer PFOS is commercially used in the treatment of leather, carpets, paper and fabrics. What is the full name of PFOS which mainly consists of carbon and fluorine atoms? 7. "Bird in a cage" is an arrangement displayed in many science exhibitions in which pictures of a bird and a cage are drawn separately on the opposite sides of a cardboard/metallic sheet. When this sheet is rotated at high speed, the bird appears to be trapped inside the cage. What is the name of the basic principle of this optical illusion? What is this arrangement called? 8. Type "metal" is actually an alloy of lead, tin and a third metal. Which is this third metal due to which the alloy possesses the property of expansion when the molten alloy solidifies? 9. Some animals like snakes shed their skins and some water animals cast off their outer shells. What is this phenomenon called? 10. According to the latest theory, what are the ultimate constituents of all matter? What holds these constituents together? Answer 1. Chaim Weizmann |