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Methane gas find Equinox day Spinal injury breakthrough
Prof Yash
Pal
THIS UNIVERSE |
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Methane gas find Methane is an organic molecule which can be produced by biological activity but the scientists believe that its presence on this particular planet cannot be a by-product of living organisms as temperatures there are 900C, hot enough to melt silver. However, the researchers said that just being able to detect methane on a planet beyond our own solar system shows that it is possible to find the vital signs of extraterrestrial life forms on other “extrasolar” planets more suitable to life. “Methane is an organic molecule and so even if it is not produced by biological forces in the environment of this planet, finding methane in another planetary environment could indicate that life might be there,” said Giovanna Tinetti, of University College London, who took part in the study published in the journal Nature. “We haven’t found life on another planet yet, but this is an exciting step towards showing that we can detect these signature molecules where they are present in the universe.” The extrasolar planet, known as HD 189733b, is composed of hot gases and is similar in size to Jupiter. It orbits close to its star, with each orbit lasting just two Earth days, and is “locked” so that one side faces its sun and is bathed in constant radiation, whereas the other is in constant darkness. The Independent |
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Every day Sun rises and sets but have you ever noticed the directions where it rises and sets? If you have, then you must have realised that sun never rises in east everyday and never sets in west every day. So is there any day when it actually does happen? Equinoxes are the days when you have sunrise and sunset exactly in east and west. But does it imply that on these days we have day and night equal? The word equinox derives from the Latin words aequus (equal) and nox (night). Just get hold of any newspaper on the equinox day and see the times for sunrise and sunset. You will be surprised to see that day and night are not equal. So where is the problem? In practice, at the equinox, the day is longer than the night. Commonly the day is defined as the period that sunlight reaches the ground in the absence of local obstacles. This is because the Sun is not a single point of light, but appears to be a disc. So when the centre of the Sun is still below the horizon, the upper limb is already visible and emits light. Furthermore, the atmosphere refracts light downwards, so even when the upper limb of the Sun is still below the horizon, its rays already reach around the horizon to the ground. These effects together make the day approx 14 minutes longer than the night (at the equator, and more towards the poles). The most dramatic example of this effect is at sunrise or sunset. In the diagram, if there was no atmosphere then when the Sun is at position A, it would already be below the horizon of the observer. However, refraction causes the Sun’s rays to bend down towards the observer so that it appears to be at point B. In Delhi, day and night were equal on March 16th. This day is commonly referred to as the “equilux” to distinguish them from the equinox. The equinox is a point in time, but the equilux is day. The instances of the equinoxes are not fixed but fall about six hours later every year, amounting to one full day in four years, but then they are reset by the occurrence of a leap year. Smaller irregularities in the times are caused by perturbations of the moon and the other planets. On the day of the equinox, one can find its own latitude by observing the sun angle (angle made by sunrays with vertical) at local noon. Well, that’s another story to tell.
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A pioneering technique that uses the body’s nerves to bypass spinal injuries could help thousands of people to regain feeling, and possibly even the use of paralysed limbs, scientists say. Using similar principles to heart bypass surgery, where veins from a patient’s leg are used to get around an artery blockage, scientists in the US have shown that nerves can be used to circumvent spinal damage and reconnect the brain to the body. The procedure, successfully used in experiments with rats, raises the prospect of the first human trials within five years, offering rent hope to people with spinal cord injuries. Researchers know that the part of the spine below an injury is often capable of responding to electrical signals, but because it is isolated from the brain it cannot control anything. According to a report in New Scientist, in experiments on rats with spinal injuries, a team led by John Martin, a neuroscientist at Columbia University in New York, cut away a nerve from just above the injury that normally stretches into the body to control abdominal muscles and reattached it to the spine below the injury. The rats went on to show an increase in movements of previously-paralysed limbs, Martin told a meeting of the New York state spinal cord injury research programme. “What we’ve documented is that we’ve reconnected the nervous system above the injury with below the injury in a robust way,” Martin told the Guardian. The Guardian |
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THIS UNIVERSE
CO2 is a poisonous gas. But why it is used for making soda? Can we use other gases to prepare soda? CO2 is not that poisonous. It is a product of metabolism in which oxygen is used to convert the food we consume into energy. The gas forms, after oxygen and nitrogen, the most significant component of the atmosphere. But it must be remembered that CO2 dissolves in water to form carbonic acid. This might be partly responsible for the taste of sodas and colas that we like. Another reason for using carbon dioxide in aerated drinks is that under pressure a large amount can be absorbed in water or syrup and when it is continuously emitted after a bottle or a can is opened we get a pleasant fizzy tingling feeling. I think the soft drink makers discovered a perfect gas for imparting a generally pleasing sensation while drinking plain or syrupy water. I can think of no other gas that would do. It is possible that the fashion arose because some of the real natural mineral waters are also slightly fizzy and loaded with carbon dioxide. Nobody can claim that the habit of drinking colas is good for health. Like tea and coffee they also contain caffeine and therefore
habit forming. It has been argued that colas are injurious to our teeth because of their sweetness and acidity — one could say that colas are nothing more than sweetened and flavoured carbonic acid, with some additional carbon dioxide under pressure to provide a fizz to our tongue. One can, of course argue that the habit of cola drinking is not as deadly as several other things that we consume. How are shooting stars formed? Are they harmful? Shooting stars are not stars. They are called meteors. If a bit of dust or a rock moving about in the interplanetary space happens to encounter the earth’s atmosphere the collision is very violent because the relative velocity can be very high. The frictional force heats up the material with emission of bright light and evaporation of the material before it reaches the surface of the earth. A large number of such meteors hit the earth every day. Occasionally a big rock comes in that is not completely vapourised in the atmosphere. Its remnants can hit the earth and cause damage. In the history of the planet some very large impacts of this kind must have occurred and caused a major change in its morphology as also on the evolution of life on the planet. |
Scientists have for the first time detected methane gas in the atmosphere of a planet orbiting a distant star, an achievement that might soon lead to the discovery of extraterrestrial life. 
March 20, 2008, was a day for earthlings to celebrate. The day is “equinox day” and it comes twice in a year. In other words we know equinox day as the time when the sun crosses the plane of the earth’s equator, making night and day of approximately equal length all over the earth and occurring about March 21 and September 22.