Current event in Astronomy Essay
Current event in Astronomy
The best of the fire-works which lit up the sky, cannot match this spectacular show. The beauty of these fire-works is not even comparable to the beauty of this show. The fire-works travel from earth to space while the objects of this show fall from space to earth. The host of fire works which adorn the sky is man, whereas the host of this show which will adorn the sky on the night of 12 August 07 is mother nature. Comet Swift-Tuttle is very far away from the Earth, but the tail of this comet is very near to Earth’s orbit, every year in the month of August.
The tail, which is traveling at a very high speed, of about 132,000 miles per hour, intersects the orbit of Earth and breaks into small meteors. This phenomenon occurs regularly every year in the month of August. The date this year is 12 August. These meteors are known as ‘ Persieds’ because they shoot out from the constellation Perseus. The meteors will appear like a stone skipping through the surface of water of a pond. They will appear from the horizon on the night of 12-13 August 07, and skim through the sky.
The number may be less initially, but as the night advances, one may be able to see many such persieds adorning the sky. To begin with, one may witness one Perseid per hour, but once the mid night passes, this number may rise to a dozen per hour, and the climax will be reached around dawn time, when the number could be a meteor per minute. It is advisable to go to the countryside to watch this natural show. The glare of the city lights may not give the joy that the absence of the same can give. Moreover, this 12th August is a new
moon night, so there is no fear of moonlight obstructing the view. It is going to be a completely dark sky. One needs to watch the North East direction to see this spectacular show. A Perseid fireball photographed by Pierre Martin, on 12 August 06 Ontario, Canada. (Dr. Tony Philips). There is one more exciting event occurring with this show on 12 Aug 07. Planet Mars, will also be visible in the constellation Taurus, just below the Perseus constellation. Mars looks brighter than normal, and it will be difficult to take the eyes off from this planet. It is more
brighter and more reddish because Earth and Mars are converging, and will be nearest to each other in December 07. Mars, unlike other planets and stars, does not twinkle. (Dr. Tony Phillips) The Eastern sky as it would appear before sunrise on 13 August 07. (Dr. Tony Phillips) What is the science behind the spectacular beauty created by the meteoroids in the night sky? It is simple. Even a high school student can understand the scientific fact, behind meteors. Earth is moving at a very high velocity along its orbit. The space around is full with comets which are
also moving at high velocity. The comets are clusters of dust and rocks. If they make a head-on collision with any revolving planet, it should create a catastrophe. However, in the human history, such an incident has never happened. What has happened is that the orbiting comets leave their debris and Earth’s atmosphere clashes with this debris. The Perseid meteor shower is a result of such a brushing between Earth’s atmosphere and the debris left over by comet Swift Tuttle. The impact causes a very high magnitude of frictional forces between the rocks, dust, pebbles and the atmosphere.
As a result, these meteors immediately vaporize and form a bright patch of light for a few seconds. When many such meteors vaporize simultaneously, a shower of light beams in the sky is seen. The contemporary name of this phenomenon is ‘ shooting stars’. ( Milan Will) The Perseid Shower ( Wil Milan ) Some of the distinct features of Perseid meteoroids are :
1. Perseids are not big in size. Most of them are the size of sand grain, some are as big as peas or marbles. They enter the atmosphere at a speed of approximately 133,200 miles per hour. 2. The nucleus of comet Swift-Tuttle is about 6 miles. Perseids generate from this comet. This comet is the one which visits Earth most frequently. 3. Earlier calculations predicted that Earth will collide with Swift-Tuttle in 2026. This is now expected to happen in 3044, or it may be a miss by about a million miles only. 4. Small meteors vaporize in the temperatures cause by the frictional forces, which exceed 300 degrees F. They create the shooting star while the larger meteors create a fireball. Explosion of fireball can be heard from ground also.
5. Perseids meteoroids are 60 to100 miles apart. 6. Pre dawn time is best for viewing the meteor showers. 7. Comet Swift-Tuttle was last seen in 1992. Prior to that it was last seen in 1862, when it was discovered. 8. The next appearance of the Swift-Tuttle is expected in 2126 ( Robert Roy Britt) Conclusively it can be said that the Persieds shower is a nature given annual entertainment program. Which should be enjoyed by every one who loves nature and admires its strength. This year, this feast will be more extra ordinary because of the presence of Mars.
References : 1. Dr. Tony Phillips, Great Perseids, [email protected], 11 July 07, Retrieved on 22 July 07 from: < http://science. nasa. gov/headlines/y2007/11jul_greatperseids. htm > 2. Wil Milan, Perseid meteor shower peaks this weekend, space. com, 10 August 2000, Retrieved on 22 July from: http://www. space. com/scienceastronomy/solarsystem/perseids_shower_000809. html 3. Robert Roy Britt, Top ten facts: Perseid meteor shower, space. com, 10 August 2004, Retrieved on 22 July 07 from: < http://www. space. com/scienceastronomy/perseid_facts_040810-10. html >