StarShine Magnitude

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The students here decided to ask Gilbert Moore about the visiblity of
Starshine here is his reply.

>A single mirror will have a visual magnitude of +1 when the spacecraft is at
>an elevation angle of 10 degrees, when the mirror is at a zero phase angle
>relative to the observer, and the Sun is directly behind the observer.  When
>the spacecraft is directly overhead, the brightness will increase to -1.
>(These values do not take into account the effects of atmospheric extinction
>or light pollution.)  
>
>We plan to rotate the spacecraft about an axis parallel to the local magnetic
>field vector at a rate of 1/2 rpm, so that the flash from a given mirror will
>have a duration of approximately 1/10th second.  With nearly 1000 mirrors
>distributed uniformly across the surface of the spherical spacecraft, a given
>observer should see a flash every 10 seconds or so.
>
>Unfortunately, however, the satellite will have essentially no "average"
>brightness, in between flashes, since it will be covered almost completely by
>the mirrors, which, except for the one that is reflecting to the observer in
>question, will all be reflecting sunlight away from that observer.


Regards Steve Daniels
I.T. Technician
Brixham Community College
50.245N 3.34W 210ft

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