SCIENCE TRIBUNE | Thursday, May 4, 2000, Chandigarh, India |
Planetary alignments Myth and reality by Ravinder Singh WE usually hear warnings from astrologers and doomsayers about the lining up of the planets. Every few years, they start to relate this phenomenon with the earthquakes, floods, doomsday etc. Such thing happened last year, when newspapers cautioned the public on similar happenings. But the predicted events were not to occur in the year 1999, but are due in the year 2000. Ultimate remote control Cybersurfing
with Amar Chandel Science
Quiz |
Planetary alignments WE usually hear warnings from astrologers and doomsayers about the lining up of the planets. Every few years, they start to relate this phenomenon with the earthquakes, floods, doomsday etc. Such thing happened last year, when newspapers cautioned the public on similar happenings. But the predicted events were not to occur in the year 1999, but are due in the year 2000. In an ideal situation, if the planets lie on the same side of the sun and the line passing through their centres is a straight line, then only can we say that they are aligned (See fig.). If planets were ideally aligned, then it would mean that one planet was eclipsing part or the whole of another planet. But in the case of planets, this ideal situation never arises. Throughout human history no one has ever witnessed alignment between all five planets visible to the unaided eye. Although planetary alignment is a rare phenomenon, the appropriate question in this context is: over how many degrees the directions of all the considered planets are scattered around the sky. The year 2000 began with the planets (Mercury, Venus, Mars, Jupiter and Saturn) dispersed over 160° of sky. During first four months, Mercury and Venus are visible in the morning sky, while Mars, Jupiter and Saturn are visible in the evening sky. On February 28, their angle of separation reduced to 90°. On March 15, Mercury and Venus were only 2.1° apart and on April 6, Mars and Jupiter were 1.0° apart. The angle between five planets further reduced to 30º, on April 28. On May 5, all the five planets, moon and sun will come within an angle of 25° 53. Finally, on May 17 these celestial objects (now excluding the moon) will subtend their smallest angle of separation, i.e. 19° 25. During these alignments, all the planets will be on the far side of the sun. A planet is affected by two factors. First is the gravity i.e., how hard a planet can pull on us. Second is tidal force. We can think it as a stretching force. Gravity depends on the mass of the object and its distance. The more massive is the object the stronger is its pull, whereas if the distance between two objects is greater, they pull each other less. The strength depends on the square of the distance (inverse square law). Now if we put two objects 10 times farther away, the gravitation force drops by 10x10=100. Here the tidal force is less important because of the fact that it decreases with the cube of the distance. So, if we know the mass
and distance of an object, we can calculate the
gravitational force as well as the tidal force. Moon is
our nearest neighbour, so it has the largest effect on
us. (Tides in the oceans are caused as a result of tidal
forces of the moon. But in this case, we are only
considering the gravitational effect of the moon. The
gravitational force is far more powerful than the tidal
force. To make things simpler, lets say that the
moons gravitational force on the earth is equal to
1 unit. In these terms, the gravity of 5 units means that
the planet pulls on the earth five times as much as the
moon does. Jupiter is the king of planets in terms of
size and mass. its equatorial diameter is 1,42,984 km and
its mass is 1.900 x1027 Kg. Jupiters mass is 25,857
times than that of the moon, but it is 1620 times farther
away. After simple calculation, we find that the Jupiter
pulls about 1% as hard as the moon does. Venus (closest
planet to the earth) pulls about 0.6% as hard. Even if
the total pull of all the planets is combined (if we
assume that all planets lie in a straight line), the
figure comes out to be not even 2% of the moons pull. We
can clearly see that these figures turn out to be almost
negligible. Hence, we can conclude that planets do not
affect us at all. |
Ultimate remote control A novel feature incorporated into electronic gadgets in the recent past is the facility of remote control operation. Manually operated gadgets are yielding way to the ones with remote control facility since the remote control operation makes life easier. A remote control system has two basic units; a hand-held device that generates a coded electromagnetic signal and a receiver-cum decoder fitted into the gadget to be operated by the remote control. Coded signal from the hand-held device is picked up by the receiver, the signal is decoded and the operation assigned to that particular code is performed electronically. The person using the remote control thinks of the operation to be performed and by mechanically pressing the appropriate button on the hand-held device controls the working of the gadget through the receiver-cum-decoder. Obviously, the first step in the operation of the remote control is the thought process i.e. a brain wave. The brain wave is translated into the desired operation through muscular movement in the form of pressing of the appropriate button on the hand-held device. This mechanical action at a distance generates the coded signal that is picked up by the receiver which in turn activates the controllers in the gadget. Brain wave dictat is accomplished through muscular movement. Now visualise the scenario where the signal associated with the thought process, the brain wave itself, is picked up by the receiver-cum decoder and direct control of the gadget operation takes place without the involvement of the hand-held device and the muscular motion. It is an established fact that an electrical signal is produced with the thought process and the electrical signal is linked with the firing of the neurons in the brain. In other words the new device would, in fact, be a remote control without the hand-held device. In such a device the receiver-cum-decoder picks up the brain waves directly and controls the operation of the gadget without the intermediatory hand-held device. This kind of remote control operation may appear a bit far-fetched to some and a pure piece of science fiction to others but such devices are within the realm of the possible. Experiments have been performed by neuroscientist John Chapin the USA in which electrical signal associated with the thought process in a rat was picked up directly and used to activate a mechanical device without the intermediate step of muscular movement by the rat. In Chapins experiment a rat in a cage was trained to depress a bar that swung a metal arm which is turn delivered a sip of water in a cup placed inside the cage. The rat was fitted with 24 microelectrodes around that portion of the rats brain which controlled its paw movement. It was established that activity in the brain just before the rat pressed the bar carried a code for how far the bar has to be pressed in order to get water. The signal from the brain was used to see if the bar could be pressed by a device controlled by the brain wave directly to get water in the cup. Surprisingly the mechanical metal arm was moved through the distance that was needed to get a sip of water. In this experiment brain wave has been used to control the working of a device at a distance without the involvement of muscles. This is the first step towards the development of thought driven machines. The foundation of the pioneer machines that translate thought into action, the ultimate remote control, has been laid by Chapins experiments on rats. A field where thought-driven machines have been tested on human beings is that of neuroprosthetic devices. The ultimate beneficiaries of brain wave driven devices are thousands of completely paralysed patients some of them cannot even blink. For such patients a tool that could read their thought to execute commands or translate them into written language through a computer would become a lifeline to the outside world. This would really be a boon for locked-in patients. Quick advances are being made in neuroprosthetic device technology. A first generation of communication devices driven by brain waves, detected from outside the body or by electrodes implanted in the brain, has been tested with certain degree of success. An exciting and surprising feature noted by researchers in the field is the adaptability of the human brain to treat a cursor on a computer screen or a robotic arm as an extension of the self. Researchers were convinced that human beings can control their electroencephalo grams (EEG), the brain wave pattern detected by electrodes placed on the scalp. EEG is the electrical signal associated with the brain activity that can be detected by electrodes placed in the scalp. Patients were trained to use their EEG pattern to control the cursor movement on the computer screen and to spell out words. The speed was slow but for those who had no communication with the outside world at all some slow communication is a divine gift. Improved results have been obtained in experiments in which electrodes have been implanted inside the brain rather than outside on the scalp. Now that neuroscience
has shown that the human brain has the potential to
control prostheses directly, it is only a matter of time
before neuroprosthetic devices become common and help the
incapacitated patients. In principle, the possibility of
thought control machines has been established and the big
question is to what degree and when such machines will
become available on a commercial scale. |
Cybersurfing with Amar Chandel It must have happened to you also. You send an e-mail and avidly await a reply. It never comes. You contact the recipient through some other means, only to be told that he or she never got it. You have no way to know whether the e-mail got lost on the way or the person concerned is fibbing. Well, there is a solution at hand. The website www.certifiedmail.com has come up with an add-on which sends a separate message to the recipient informing him that a message is waiting for him at an e-mail box. The software notes the date and time on which the message is read and informs you about it. The add-on seamlessly integrates with MS Outlook, Express and MS Exchange Client. It is a 180 kb file that users download from the website and install on their computers. You can even send messages directly from MS Word. Send Certified automatically encrypts and digitally fingerprints the message and attachment without any user intervention. That makes sure that the e-mail reaches the recipient without the possibility of any alteration. The recipient does not have to install any additional software. *** Leher is an Indian band based in Detroit which has been performing before live audiences in Canada and the USA. It has become the first Indian band to provide streaming music clips of their songs on the Net. These can be accessed at http://oeonline.oeonline.com/~leher. There are not too many songs in their repertoire but the few that are there (Indi-pop, bhangra and old Bollywood numbers) have been well done. If Net congestion does not strike, they provide a good source of Indian music. *** Internet is all the rage but still there are many things which one does not know. One way to learn them is to join a professional course. The other method, of course, is trial and error. Hold on! There is a third option available. You can learn many tricks online, for free. This cyber course is available at www.newbie.com. This training workshop has been designed to assist people who have some (between a few months to a few years) experience of using the Internet. For those who are absolutely new to the world of Internautics, there is an orientation course also. The lessons are all
self-paced and promise to make knowbies out
of newbies. |
New products & discoveries Drive-in-wheel
car And some of the results were truly technological marvels attractive novel and very practical. An engineer came up with a workable Drive-in-wheel car, which is designed like a wheel into which the driver sits and drives around wherever he or she wants to go. Though it may be absolutely impractical on the roads, the contraption has found interested buyers in many amusement parks around the world. It may go into production soon. Worlds
first opium-less poppy The variety Sujata was developed at the Lucknow-based Central Institute for Medicinal and Aromatic Plants (CIMAP), a laboratory under the Council of Scientific and Industrial Research (CSIR). The opium-less and alkaloid-free poppy developed for the first time in the world has heralded a new era of opium poppy cultivation which need not be licensed, JR Sharma and colleagues from CIMAP report in Current Science. The opium-free variety could be used as a food crop as it is rich in proteins and oil. It was developed through a programme initiated by CIMAP in 1994 in which scientists systematically converted narcotic opium poppy into a non-narcotic crop by inactivating the opium gene through mutations. The new variety does not contain opium in its latex, fruit or straw. But it can be used as a protein and oil-rich food crop, with a high calorie value. Test tube
mangoes Scientists had in the past achieved some success in tissue culture growing tiny pieces of a plant on a special nutrient medium to give rise to hundreds of plants of the popular Alphonso mango variety and few others such as Mundan, Baneshan and Arka Anmol. Now the BHU scientists have developed a method to grow two more popular varieties Amrapali and Chausa. The BHU scientists have succeeded in raising tiny plants, called plantlets, of Chausa and Amrapali varieties by growing miniature pieces of nucleus tissue inside the fruits ovule on a special nutrient medium supplemented with salts and growth hormones. The ovule contains the embryo surrounded by the nucleus and eventually forms the seed. While Amrapali plantlets survived in pots containing garden soil, Chausa plantlets grew in pots containing a mixture of sand and soil, a report by BHU scientists V.S. Jaiswal, Hussain Ara and Uma Jaiswal in the journal Current Science says. New antibiotic
in sea snail The sea snail, called common dog whelk, uses the antibiotic to sterilise its eggs to protect them against infection, says Kristen Benkendorff, the researcher from Wollongong University. The discovery can provide an answer to the problem of bacterial resistance to currently available antibiotics, according to a report in Ascent Technology Magazine. At concentrations half as low as penicillin, the compound tested active not only against marine bacteria, but against human pathogens including Staphylococcus, E-coli, Candida and the bacteria that cause pneumonia. The new
antibiotics chemistry is different from all known
antibiotics and it is non-toxic to humans. |
Science Quiz 1. When a student approached the British physicist Lord Ernest Rutherford for doing research work in nuclear physics under his guidance, Rutherford suggested, Choose another field since work in this field has been completed. What was Rutherfords discovery which was only a beginning to a vast store of knowledge hidden in the atom and thus falsifying his statement? 2. This radiation is considered the remnant of the hot, early universe created by the Big Bang and provides strong evidence for the Big Bang theory. What is this radiation called and who discovered it? 3. MAP, the 800-kg probe to be launched by NASA this year, will measure the properties and temperature of the background radiation of the universe to an accuracy of the order of one millionth of a degree. These measurements made by MAP will provide vital information about the size, matter content, age, geometry and fate of the universe. What is the full name of MAP? 4. Taking a glass of milk with sugar is the grannys prescription for having a good sleep at night. Which chemicals are there in milk and sugar which induce sleep? 5. To focus attention on the significance of a heavenly object for man, the world observes on May 3 every year an International Day. Which day? 6. Oil gas is generally used in the laboratory for heating and is obtained by thermal cracking of kerosene oil. Which gases constitute oil gas? 7. The animal chimpanzee is known to have genetic structure most similar to that of man. Scientists have recently found that an insect also has genetic makeup similar to that of man. Apart from round worm, the genetic structure of this insect has been completely decodified. Can you name this insect? 8. For radio or TV transmission, electrical signals from a microphone or a TV/video camera are mixed with an electromagnetic carrier wave of a suitable high frequency. What is this process called and what are the two types of this process? 9. Which is the first known system of a normal star outside our own solar system which has at least three orbiting planets each much larger than the earth? 10. Name the Indian garden where a fossilised tree trunk, estimated over 20 million years old, is located. Answer 1. Atomic nucleus 2.
Cosmic microwave background; US scientists Robert Wilson
and Arno Penzias in 1965 3. Microwave Anisotropy Probe 4.
Melatonin and serotonin respectively 5. International Sun
Day 6. Hydrogen, methane, ethylene and carbon monoxide 7.
Droso philla fruit fly 8. Modulation; Amplitude
Modulation and Frequency Modulation 9. Upsilon Andromedae
10. Botanical Garden, Ooty (Karnataka). |