"DougD" wrote in message
...
In article , "Von Fourche"
wrote:

To see an Iridium flair, how close does on have to be to the track? Does
one have to be right under the track or can one
be a few miles away and still see the flair?

Thanks.



It's more a matter of what level of drop off of the reflected light are
you
able to see. The further from the track you get, the less reflected light.
If you use Heaven's Above, they provide the base intensity expected
at the track, say -8 (-9 being the maximum for the Iridium's), and then
the predicted intensity based on your observing position based on
your observing spec's that you enter. As you move further off track,
the intensity will drop, so for say Irid 21, with a base of -8, at my
location
4.5km east of the track, it drops to -7. There is a -9 Irid 66 tonight, my
location is 33km east, the predicted intensity is 0. I tend to only try to
spot IRD's that are within 10km or less from my location, so that I'm
not trying to spot less than -5 or -6's..



Thanks. I did see my first flair. I was about a month or so ago. It was,
I think ten miles or so away. I saw it
moving fast across the sky and got brighter for a few seconds, then dropped
down to it's original brightness.