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Dear etaoin: I should think comet orbits would be limited in size or they would be totally
disturbed by passing near some high mass object.
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Carpal Tunnel
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well, of the several sites I've just explored, this one seems to have the most info: http://www.amsmeteors.org/showers.htmlthis is good too: http://www.astronomynotes.com/solfluf/s8.htmthere is so much information out there, I'll need to take the week off to get through only a small portion of it!
formerly known as etaoin...
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Carpal Tunnel
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From the link you gave, etaoin, the frequency of flashes is influenced somewhat by rotation
of earth:Over the course of a night, it will be noticed that more sporadic meteors can be
seen in the hours before sunrise than in the hours after sunset. This is due to the motion
of the Earth as it revolves around the sun, with the leading edge (morning side) of the Earth
encountering more meteoroids than the trailing edge (evening side). In general, 2 to 3 times
as many meteors can be seen in the hour or so just before morning twilight, than can be
seen in the early evening. Additionally, the numbers of random, or sporadic meteors will
also vary from season to season, due to the tilt of the Earth on its axis and other factors.
As a general rule, about 2 to 3 times as many sporadic meteors can be seen in the early
fall (September) as can be seen in the early spring (March). Together,these two effects
can generate a fluctuation in the hourly rate of sporadic meteors by a factor of 4 to 9 times,
over the course of the year.
But difference in trajectories that Wordwind was interested in seems to be quite small.
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old hand
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old hand
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But difference in trajectories that Wordwind was interested in seems to be quite small. ~ wwh
Maybeso Bill, but I saw a website (NASA maybe) where the visual simulation of the (then) upcoming leonids showed them streaking in different directions from a central, but large sector of the sky. To me the relative motions, as you have outlined, would all come into play, but the size of the shotgun scatter pattern of these cometal pieces of rocks as they follow the path of their orbit would be the determining factor inasmuch as what direction their fall would take relative to an observer on earth. That is, if the scatter pattern was larger than the diameter of earth the fact that the individual positional extremes would still be directed towards the single atom at the center of the earth (Hi Hogwash) and that would insure that they would be viewed as streaking in different directions by an observer at any point on earth.
Well. It could not be otherwise and still be within our current understanding of what is.
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Carpal Tunnel
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Well, a big thank you! to all of you! You've put my mind to ease. I wasn't seeing things.
Now my children here at school, upon hearing me say I'd seen a couple green fireballs, told me that they'd also seen blue and red, which I did not observe. The only colors I saw were green, gold, and white.
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Carpal Tunnel
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The only picture I could find showing different trajectories was taken as a time exposure
witha fish eye lens, which showed tracks at angles due to distortion and time difference.
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Carpal Tunnel
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Here's you a picture: http://antwrp.gsfc.nasa.gov/apod/ap021127.htmlThere's some time lag due to this being thirty one-minute exposures but I don't think there is any noticeable directional distortion caused by that. Think of what it looks like to be driving into a snow storm and the snow is coming at you; if you are going fast enough that your motion is the main component, the snow will appear to be radiating from a point somewhere in front of you. How far off directly in front of you will depend on the speed and direction of the snowfall. This is pretty much the same thing as what is happening in the meteor shower. What? You don't drive in the snow in Virginia? Well, you oughta try it sometime. It's fun.
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Who said I don't drive in snow in Virginia? I drive all over the place when it snows in Virginia. Driving in snow is one of my favorite things in the whole world to do. 4WD is the thing that makes it all possible. You know I must be crazy about driving in snow in Virginia just to have a 4WD that I use approximately 1.5 times a year.
And thanks, Fald, for the fantastic!!! photograph! That really does show a little of what I thought I was seeing. How very, very exciting to see that time-lapse photograph! I cannot wait till the next big meteor shower so now I'll know what to look for--even though W'On has told us that this is the biggest we'll see for another 30 or so years.
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Carpal Tunnel
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Fascinating thread! Thanks to everyone!  Here's the official Nasa Leonid site (and be sure to click on Leonids Live over in the left column, then "Photographs" > "Image gallery" for 445 Leonid meteor images from 27 different countries!): http://leonid.arc.nasa.gov/
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