I remember seeing a meteor shower in 1998 which was very interesting and wonderful. Truly I watched that phenomenon in Awe. The same kind of meteor shower but in a more aggressive manner is going to take place on Nov 17 2009. This shower is particularly a Leonid Meteor shower, which will be seen more prominently in Asia (expected over 200 meteor per hour) though it is also observed over North America( expected 20 to 30 meteors per hour) .The New Moon sets stage for Brilliant Leonids Meteor Shower, when the shower will be well up in the dark southeastern sky. The time frame for the most intense activity is anticipated sometime around 21:40 GMT
The current years leonid shower is mostly due to Cosmic garbage or bits of debris left by Comet Tempel-Tuttle. So let us all get ready to see this astronomical phenomenon (that are actullay very rare and spectacular)which is expected to hit earth with high intensity around 21:40 GMT on Nov 17th 2009
Why it is called Leonid Meteor Shower???
The point in the sky from where the meteor shower appears to come from is called the radiant of the shower and the shower is named after of the constellation in which its radiant lies. The meteor shower of November due to the Earth's passage across the orbit of the comet Tempel-Tuttle is known as Leonid because the radiant lies in the Leo constellation.
Approx timing Asia(India): Around 2:30 a.m i.e early hours of Nov 18th(showers may continue for few hrs)
As it interests many on the topic of space....I have collected some more interesting information on what meteors are all about…go through the following article:
Wish upon a Shooting Star
When we see a streak of light in the sky, rather like a bright little star falling down, we call it a shooting star. Astronomers call it "meteor". When an interplanetary particle traveling at high speed enters into the Earth's atmosphere, it ablates due to the energy produced by its friction with the atmospheric constituents. Such a particle, called a meteoroid, can be about as large as a pea, a few millimeters in diameter. Smaller grains may produce a meteor so faint that it can be seen only through a telescope. On the other hand, a bigger meteoroid can produce a meteor as bright as Venus. Such bright phenomena are called fireballs, which can be seen in broad daylight. (Remember Venus can be seen even when the Sun is above the horizon.) Sometimes a fireball also makes a noise as it rushes through the atmosphere of the Earth. Some of these fireballs may explode in the sky - they are then called bolides.
Extraterrestrials of different kindsIt is believed that meteoroids were formed at the time of the formation of the solar system and meteorites can give us clues of the condition prevailing during that period.
Meteorites are classified into three broad categories : Stones, Irons and Stony irons. Stony meteorites account for nearly 93% of all meteorites but owing to their close resemblance to the terrestrial stones they are difficult to discover. A freshly fallen stony meteorite may have a fusion crest which would be produced by its outer surface melting during the plunge.Iron meteorites account for about 6% of meteorites. They contain about 90% iron and about 9% nickel. In 1620 an iron meteorite was picked up at Jalandhar, Punjab. It weighed about 1.6 kilograms. Emperor Jahangir asked his artisan to make weapons out of it. The artisan found that the composition of the meteorite was "rather less dense" than required to make strong enough weapon. He added one part of iron to three parts of meteorite material to make two swords, one knife and one dagger.
Stony iron meteorites consist of about equal amounts of rock and iron. They look like small pieces of stone set in iron. Some carbonaceous chondrites, which belong to a class of stony meteorites, contain amino acids, which are the organic building blocks of life-sustaining proteins. It has been suggested that they may have played a role in the appearance of simple organisms on our planet about 4 billion years ago.How meteoroids burn
We observe meteoroids as "shooting stars" as they burn in the Earth's atmosphere. Usually a meteoroid starts burning at the height of about 140 km above the surface of the Earth and burns out completely in the atmosphere. A fireball may travel down to an altitude of about 50 km before it disappears.
Meteoric phenomena lasts from a fraction of a second to a few seconds. A meteor may leave behind a trail of ionized gas. This trail can be seen for as much as half an hour under undisturbed atmospheric conditions. The speed of a typical meteor in the atmosphere can range from 12 km per second to 72 km per second.On any clear dark night, one is expected to see a meteor every few minutes. It can come from any random direction in the sky. However, there are certain times of the year when meteors can be seen coming from a particular direction in the sky in large numbers.
Four hours before dawn on November 13, 1833, people of eastern North America saw what no one had seen ever before. The sky was almost lit up by large number of meteors. It was a heavenly firework. Among those who witnessed the display was one Denison Olmsted. He observed that meteors were coming from a particular point in the Leo constellation. He estimated that up to 150,000 meteors were observed in an hour. He then further investigated observations of this extraordinary display. He found that similar display was seen at other places too. In Jan 1834 he presented result of his investigation. He in his report he rightly suggested that the meteors had originated from a cloud of particles in space. Olmsted, however, no explanation for the nature of the cloud.
When a comet approaches the Sun, volatile material trapped inside its stony shell sublimates, breaks the shell and escapes forming a cloud of gas and dust, called coma, around the comet. Fragments of the shell gets scattered in different directions. But most of the debris go to form the tail of the comet and follow the same path as that of the comet. Over a period of time a ribbon of debris is formed along the comet's orbit.
If the orbit of the comet and the Earth intersect or lie close to each other, then every year when the Earth passes close to or through this point it would experience a surge comet's debris entering into its atmosphere. Of course, the probability of the Earth colliding with the comet itself may be negligible.The point in the sky from where the meteor shower appears to come from is called the radiant of the shower and the shower is named after of the constellation in which its radiant lies. The meteor shower of November due to the Earth's passage across the orbit of the comet Tempel-Tuttle is known as Leonid because the radiant lies in the Leo constellation.
Observations of meteor showers are ideally suited for those who are unable to invest inexpensive observing apparatus. The study of meteor showers can give us a lot of information about the parent comet and its constituents. All you need is a good eye. There are about a dozen meteor showers which we know are good to observe so you can make your plans well in advance. The observations can be carried out in a very comfortable position. In fact you simply lie down and look up. Such a project can be undertaken by individuals or by a team of observers. However, if you do not choose the proper time to observe your first shower, you are likely to find this game very boring: so one must make a good start. Once you get used to it, it is fun.
(Courtesy: IUCAA pune-public outreach website)
Indi Proff
http://indiproff.blogspot.com/
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