posted on Apr, 19 2012 @ 09:26 PM
Originally posted by defcon5
Technically I believe that a grazer is going faster as it is not interacting with the thicker air for as long a period, but you can see them longer.
None of that is going to change the other features that are common with fireballs.
You are right about the first part, but I would argue that earthgrazers have quite different characteristics compared with meteoroids hitting at
higher angles, not just the unusually long path across the sky.
For example, because of the low entry angle, an earthgrazing meteoroid will not experience as traumatic an atmospheric entry as a meteoroid with a
high entry angle. Many meteoroids (because they are relatively fragile), will disintegrate/break up if they hit the atmosphere at too high an angle
and/or going too fast, where as they would not at lower entry angles.
The result is that earthgrazers tend to be more constant in brightness over their flight path, whilst meteoroids with higher angles will tend to
brighten/flare more randomly as they break up, and larger/faster ones that are made of more fragile material often just disintegrate in a blinding
flash of light almost immediately when they hit.
Another example is the meteor train or trail, which may be much less obvious, or even missing altogether with grazers, since it's made up of plasma
created from atmospheric molecules (such as oxygen and nitrogen) mostly, and because of the low densities a grazer encounters, there may not be enough
for a train/trail to be visible.
There are other characteristics such as the difference in perspective will affect the apparent angular speed of the meteor - read more on the subject
edit on 19-4-2012 by FireballStorm because: fixed typos