Re: SL-16 (26076)

>Has anyone seen SL-16 (listed as bebris)? Catalog number 26076.
>Heavens-Above has the magnitude listed as 4.4 but I have never 
>been able to see it using my 7x50 binoculars or with the naked 
>eye. I have looked for it several times using the Heavens-Above 
>star charts to get an accurate location to look.

Mike McCants' RCS file, which averages USSTRATCOM's measurements 
of radar cross-sections of objects, lists 26076 as .1 square 
meter -- a very small object.  As Bill said, it could be an odd 
shape that sometimes reflects much more brightly than others.

Magnitude estimates have to be well understood.  They are 
estimates based on available information.  Some objects are 
consistently observable near estimated magnitudes, but others 
vary much more.  Quite a few payloads can vary wildly from 
estimates if flat surfaces are nicely aligned for bright 
specular reflections.  Some big launch vehicle stages are
badly aligned, say pointing directly at the Earth's surface,
and may be invisible when they should be +3.5 magnitude.

Here's the link to that RCS file:

http://users2.ev1.net/~mmccants/catalogs/rcs.zip

Ed Cannon - [EMAIL PROTECTED] - Austin, Texas, USA