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At 01:08:38 UT on this night an unknown satellite trails through the field of view. It's pretty faint.
At the mid-point of the 50-second exposure (arrow), the satellite's position is RA= 09:09:04.07 and
Dec= +09:36:17.2, and it's in the sky at alt= 57.092 degrees and az= 148.934
degrees. It's moving west to east (right to left) at a rate of 9.89 arcsec per sec. The brightest flashes
compare with the 15.1 magnitude star, ZN075:0900 (circled). The 4-flash cycle in the satellite's image
trail shows that, in the space of 50 seconds, the satellite has tumbled about 5½ times.
Can we learn anything more about this object? There would be several questions we'd need to answer first:
How high is the Earth's shadow? (the satellite is in the sun, after all)
How high is the satellite (it has to be above the Earth's shadow)?
How fast is a satellite at that altitude actually moving? (in meters per second)
Is that in agreement with the angular rate of motion we see here? (9.89 arcsec per second)
If we get all this, can we make an estimate of its size based on it's apparent magnitude?
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