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Re: Iridium Flares

> I have also been watching Iridium flares ..

Me too, and it is something special.

> FYI, a magnitude '0' is about
> the same brilliance as a NOAA weather satellite ... that's to say that it's
> relatively dim (to *my* eyes, anyway).  You have to be closely watching the
> correct region of the sky or you'll miss a Mag 0.  In addition, moonlight
> easily washes a Mag 0 out. 

I don't think this is correct.  Assuming that you are referring to visual 
magnitudes, all but about 4 of the stars in the sky are less than magnitude 0, 
so if you can see stars at all, you can see magnitude 0.  Even MIR is slightly 
dimmer than magnitude 0, and it is un-missable.  You are right, that NOAA 
sats are relatively dim, but they are MUCH dimmer than magnitude 0.  
Moonlight will NOT wash out Mag 0 . Magnitude 0 is generally related to the 
brightest stars in the sky, not dim stars.  People can see stars down to 
magnitude 6, which is about 250 times dimmer than magnitude 0.  This is why 
this Iridium thing is so spectacular, since the mag -7 flares are 630 times as 
bright as magnitude 0, ie hundreds of times brighter than the brightest stars in 
the sky.  

After seeing the Iridium a couple of times, I realized that I had seen them 
before, but had mistaken them for airplane landing lights.

| Bill Jones, N3JLQ,Sweden, Maine  Zone 4 1/2  |
| wejones@megalink.net                         |
| http://www.megalink.net/~wejones             |