|SCIENCE TRIBUNE||Thursday, October 4, 2001, Chandigarh, India|
Turning outer space into a theatre of war
Galaxy in the middle
The busiest inventor: Edison
Turning outer space into a theatre of war
The USA, which is busy exhorting every other country in the world to renounce weapons of mass destruction as a step towards lasting world peace, has been vigorously pushing ahead with plans to turn the tranquil outer space into the battlefield of the future. Indeed, for many years the pet thesis of Pentagon has been that a robust military space infrastructure will be essential to win future conflicts. Meanwhile, the US defence forces are assessing the vulnerability of all satellites in orbit to possible collateral damage from high powered lasers being tested by the Pentagon.
Pentagon is taking all precautionary measures to ensure that spacecraft are not damaged when two types of laser systems — the US Air Force’s air borne laser and the US Army’s Tactical high energy lasers —are tested on a regular basis. The airborne laser, which is slated to begin tests in 2003, will be fired from an aeroplane flying in the upper atmosphere. The Tactical High Energy laser which was first tested in 1999 will undergo a series of trials as part of the move to deploy it for field use.
The damaging effects of lasers on satellites have been well established. Now American laser specialists are planning to assess the effects of lasers on manned spacecraft because personnel inside the spacecraft could suffer eye damages if they look out of the window when a laser is fired in their direction. Evidently, the laser weapons combine speed, lethality and precision. Pentagon has successfully tested the feasibility of using "hit and kill" satellites to immobilise the enemy spacecraft constellation. In a recent series of tests carries out over the Pacific Ocean, the USA was able to demonstrate the feasibility of using the hit and speed satellite to cripple an enemy target through a direct hit at a closing speed of some 4.5 miles per second.
Interestingly, the Kinetic Energy Satellite programme designed to destroy an enemy satellite with a head-on collision was for sometime in the cold storage after its initiation in early 1980s. This weapon comprises a rocket tipped with an anti-satellite warhead fitted with sensors that can distinguish between many types of satellites. After its release into orbit, the warhead manoeuvres itself to ram the target satellite which it would annihilate without generating any debris in the high frontiers of space. According to William Redes, director of the army’s missile defence and technology centre in Huntsville, Alabama, an operational kinetic energy vehicle would destroy a satellite with a fly swatter-like device made of synthetic mylar material.
Interestingly, in early 1980s, the US army had launched a programme called "Sipapu" — the American Indian word for fire — for developing a particles beam weapon for anti-satellite operations. But then it was subsequently given up because of lack of funds and political support.
The array of anti-satellite devices being contemplated are directed towards putting out of commission a whole complement of satellites that work as the ears, eyes and commands posts in outer space and thus deny rival nations access into space. The US army is also keenly interested in developing a string of satellites with hyper-spectral imaging capability which will have the ability to detect objects hidden beneath camouflaging net.
Thus we see how the
ancient business of war has now infected fourth dimension after being
practised for thousand of years on land and sea and for decades in the
air. With this development, space will no longer remain the silently
tranquil, tension free canopy of our overcrowded and over-heated
planet. Indeed as one observer put it, outer space has become a
potential battle field of the future. As things stand now, any major
global war in the near future will be decided in favour of those of
who manage to control outer space.
Galaxy in the middle of nowhere?
The Solar System could be sitting at the centre of a giant optical illusion that fools astronomers into thinking distant galaxies are accelerating away from us, scientists have concluded.
In 1998, astronomers discovered that distant galaxies appear to be accelerating away from us. They hypothesised that this acceleration could only be caused by a mysterious "dark energy."
But Kenji Tomita, an astrophysist at Kyoto University, says there is an alternative explanation, a report in New Scientists said.
Observations hint at a "wall" of galaxies lying between 650 million and 1 billion light years away from in all directions, Tomita says. This suggests that the Milky Way may lie near the centre of a "local void," a rarefied region in which galaxies are scarce and space is expanding unusually quickly.
The difference in the expansion rate, or Hubble constant, would explain why studies of supernovae in distant galaxies seem to point to a speeding up in the expansion of the Universe, Tomita says.
Observers in a local void feel as if the Universe at the present stage is accelerating relative to older, more remote sources," he said.
The void scenario can also explain why a supernova 11 billion light years away appears to have gone off in an era when the expansion of the Universe was decelerating. This recent observation is considered by some scientists to be strong evidence of dark energy, demonstrating that its influence did not overcome the pull of gravity until the universe had expanded and thinned out.
But Tomita says the void would produce the illusion that closer, younger supernovae are accelerating and older, more distant ones are decelerating.
The idea faces some serious challenges, according to Mario Livio, an astrophysicist at the Space Telescope Science Institute in Baltimore, Maryland, the report said.
observations have shown that the Hubble cannot change by more than a
few per cent across distances of up to 500 million light years, while
Tomita assumes that the Hubble constant changes by roughly 20 per cent
across a distance as small as 650 million light years. "It will
have to be a very strong argument to convince me," says Livio. PTI
The busiest inventor: Edison
When Edison, the inventor of light bulb, died on October 18, 1931 at the age of 84, lights all over America were dimmed in his honour.
Edison was known for working almost non-stop all his life. He would hardly sleep for three to four hours; and that also often taking catnaps on a cot in his laboratory. "Most people overeat 100 per cent, and oversleep 100 per cent, because they like it. That extra 100 per cent makes them unhealthy and inefficient". The man who wrote these words in his diary was Thomas Alva Edison. Once his invention, the light bulb, banished darkness, the average person’s sleep time of 9-10 hours each night came down by 1-2 hours.
Edison, a genius of technology, is known as the busiest inventor. He had 1,093 patents to his name. And left 3,400 notebooks. Besides the revolutionary light bulb, his many inventions include: gramophone, motion picture camera and projector, storage battery, electric pen, dictating machine, advanced telegraph system, a new cement-making process, electricity generation, and so on.
Edison had practically no schooling. He was expelled from school after 3 months, the teacher calling him "retarded". Thereafter his mother, a former schoolteacher, tutored him. And he started work at the age of 12, selling newspapers and candy on trains. At 16 he became a telegrapher.
An attack of scarlet fever in childhood left him nearly deaf; people had to speak directly into his ear to get heard. His impaired hearing had one unexpected advantage; he could work long hours undisturbed amidst fellow workers.
Edison had a highly curious, inventive mind, fond of scientific experimentation. Even as a boy he kept a small laboratory at home. Later he was to set up the world’s first industrial laboratory. It was quite common for him to pursue 6 to 7 ideas at the same time. Edison experimented with x-rays. He discovered the "Edison effect", which laid the foundations of electronic industry. He created the Edison General Electric Company, which later merged into General Electric Company (GEC). His cement-making firm supplied bulk of cement needed for the Panama Canal. He did much work on harnessing solar energy. And late in life, he did botanical research on growing trees that could produce latex rubber.
Edison married twice, second time after the death of his fist wife, and had three children from each. But both the wives had this complaint: he remained too engrossed in his work to give time and attention to home and family.
One of his closest friends was Henry Ford, the car king; both lived as neighbours for sometime. Ford presented him with a 1916 Model T and Edison became extremely attached to this car. Another close friend was Firestone, the tyre maker.
Edison was jovial company, fond of relating jokes. And he was full of facts on almost every subject. His only relaxation was fishing. And only weakness tobacco-chewing.
NEW PRODUCTS & DISCOVERIES
Stinging enemy vehicles
The US Army’s latest tool for discouraging unwanted visitors is an autonomous munition that attacks ground vehicles.
When the Hornet detects an enemy vehicle, it launches a small projectile. The projectile’s infrared sensors locate the target, then it fires an armour-piercing shell. The Hornet can be left unattended for 30 days and can be programmed to self-destruct. Target range is 100 meters..— Popular Science
Gene therapy for blindness
Gene therapy may be used in future to halt or even prevent overgrowth of blood vessels in the eye that blinds patients with macular degeneration and diabetic retinopathy, according to two recent studies led by researchers at John Hopkins’ Wilmer Eye Institute, US.
In the studies, performed with laboratory mice, two different genes that were separately injected into the rail veins or eyes of the animals reduced new blood vessel growth by upto 90 per cent.
One gene is for endostatin, which inhibits blood vessel growth; the other is a substance that increases cell survival. The mice had conditions similar to malcular degeneration and diabetic retinopathy, the leading causes of blindness.
"These studies show that when therapeutic genes are introduced before the stimulus for abnormal blood vessel growth, they partially prevent the abnormal vessels from growing", says Peter A Campochiaro, MD, senior author of the studies and a professor of ophthalmology and neuroscience at Hopkins. PTI
Ultrasound of valvesScientists have developed a new system for ultrasound testing of miniature mechanical parts that enables any sufficiently powerful PC to serve as an ultrasound test instrument, besides being fast with high resolution.
The commonly used techniques for ultrasound testing of mechanical parts are slow and have low resolution. However, the new plug-in board system for ultrasound testing, developed by the Fraunhofer Institute for Non Destructive Testing IZFP, provides better results.
The opening and closing of tiny valves control the flow of blood through arteries. In many areas of medical engineering, valves are used to deliver the correct dose of liquids or gases, at the appropriate times.
Micro valves are also used in aerospace applications, where they are expected to operate reliably over long periods of time. This calls for extremely careful quality testing after manufacture, a report in Fraunhofer Gesellschaft said. PTI
Fibreglass "beaks" for hornbills
Wildlife Trust of India (WTI) has made fibreglass "beaks" as an alternative to hornbill beaks that are used in traditional headgear by the male members of a northeast tribe.
This would save about 2000-3000 hornbills that are killed every year by "Nishis", the largest tribe in Arunachal Pradesh, Bombay Natural History Society (BNHS) said.
Although not endangered, the combined population of great Hornbills, Oriental Pied Hornbills and Wreathed Hornbills was probably not more than 10,000 according to BNHS.
Hornbill beaks attached to the headgear not only identifies a ‘Nishi’, but is also considered a sign of manhood. WTI programme director Anirudha Mookerjee reported in the latest ‘misnet’ newsletter of BNHS.
"This also makes Nishis the largest killers of hornbills," Mookerjee said adding WTI officials persuaded powerful village chiefs in the state to break the Nishi’s age old tradition, replacing hornbill beaks with fibreglass ones.
2. Scientists in America have recently detected the possible existence of a black hole in Milky Way using a powerful instrument. Do you know what is Milky Way ? How much is its diameter?
3. Continuing on the subject, do you know what is a black hole? Which powerful observatory (named after a famous Indian astrophysicist) has been used for this detection?
4. This vegetable, normally used in salad, can help clear sinuses, ward off cancer and prevent tooth decay. Which vegetable are we talking about?
5. This plant is called nature’s vitamin capsule because it contains very high level of vitamin A compared to even fruits like mango and papaya, which are rich in vitamin A. It also has high content of vitamin B and C. Which is this perennial shrub that grows in mild humid regions and has high medicinal value ?
6. What is the area of the brain called that is most associated with learning, memory and emotion ?
7. At present the total mass of the earth separated by oceans is divided into several continents. But about 240 million years ago this land was a single continent and the ocean occupied the rest of the earth’s surface. Name this single continent.
8. Who developed the first modern printing press in Germany?
9. What is an isotope (usually an artificial one) called which is used in chemical systems to track an element by detecting radiation?
10. The Ministry of Environment and
Forests has this year chalked out a programme called NEAC. What is the
complete name of this programme the theme of which is
blindness; for propounding the atomic theory of matter