Posted on 08/08/2002 1:04:13 PM PDT by aShepard
Good view in 2002
In 2002, Earth is expected to encounter the core of the Perseid swarm, where meteoroid concentration is densest, on Monday, Aug. 12. This is when the Perseids put on their best show as the meteors appear to diverge from a patch of sky near the Double Cluster in Perseus. This is actually an illusion of perspective, since that is the direction toward which the Earth’s orbital motion carries us at this time of the year.
At the same time, the meteoroids are traveling on parallel paths nearly perpendicular to the Earth’s orbit. The combined speeds of the Earth and the meteoroids cause the Perseids to rush into our atmosphere at average speeds of 37 miles per second (60 kilometers per second).
The bane of meteor observers is bright light, natural or artificial. The Moon will be a slender crescent and will set during the evening hours, and will be of no hindrance to Perseid viewing this year.
For an observer with access to a wide-open view of a clear, dark sky, meteors should appear at an average rate of about one every minute or two. Veteran observers, however, say that the Perseids tend to appear in bunches: several over an interval of minute or two, followed by a lull of several more minutes before the sky again "bears fruit."
Comet crumbs
These cometary fragments -- countless bits of metal and stone -- are called meteoroids while they exist in and move through space.
But a meteor is not a particle of matter itself. It is merely the short-lived streak of light produced by the meteoroid as it is heated to incandescence by its plunge through the Earth’s atmosphere. (The handful of objects that hit the ground are called meteorites.) The kinetic energy released per gram of the meteoroid’s weight far exceeds the energy efficiency of the most powerful man-made explosives.
Thus, an object the size of a pea or pebble can create a substantial meteor trail. Ultimately, Schiaparelli was proven correct; comet Swift-Tuttle is indeed the progenitor of the Perseid meteor shower -- the first direct correlation to be found between a comet and meteor shower. Soon afterward, Schiaparelli suggested that another annual display, the November Leonids, was caused by Earth’s interception of the debris of the comet Tempel-Tuttle (discovered in December 1865).
Today, while not all meteor showers have been associated with specific comets, astronomers think that all showers probably have a cometary origin. More than 500 cometary meteor swarms that produce (or have produced) meteor showers are currently known.
A meteoroid swarm is sometimes referred to as a "flying gravel bank," though it is not a very compact one. The Perseid meteoroids, for example, are anywhere from 60 to 100 miles apart at the densest part of the swarm. Earth enters the outer fringes of the gravel bank around July 25 and does not leave it behind until we see the last stragglers around Aug. 18.
All told, the Perseid stream is immense -- perhaps as large as 50 million miles (80 million kilometers) in diameter.
Are you aware that there's an asteroid you will be able to see with binoculors on the 18th of this month? It'll be pretty close by and apparantly it's a pretty rare occurance to be able to see one. Come to think on it, I've never seen one.
I keep reading about nice folks that just kinda pick them up from their front yards, bedrooms, whatever.
Get yourself some cute ones!
I thought you couldn't say that on FR...
The one event I've been waiting on is Asteroid 2002 NT7 as it will be viewable by binoculars August 18th when it glides past Earth 1.3 times the distance of the Moon.
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