Modeling unidentified slow satellites

Allen Thomson (
Tue, 19 Nov 1996 05:42:41 -0800

   With regard to Lasse Teist Jensen's observation of a slowly moving 
satellite and subsequent suggestions that it might have been an object 
in a highly eccentric orbit seen near apogee, Roland Vanderspek of the 
Explosive Transient Camera (ETC) project spake thus: 

>I have just one more data point, perhaps.  Using an automated wide-field 
>(20x15 degrees in each of eight fields-of-view) CCD system sensitive to 
>m=9-10 in a five second exposure, we see lots of satellites, as you 
>would expect.  Most are streaks, many are flashes, and we see stationary 
>flashes from geosynchronous satellites as well.  Over the last six 
>years, we've seen several instances of what seem near-stationary 
>satellites at an apparent declination of about 42 degrees:  the object 
>moves very little (maybe an arc-minute or two) over 50 seconds.  For 
>this particular program, these observations are noise, and it suffices 
>that we saw it move to be able to reject it, so I don't have many more 
>details at my fingertips.  However, these crude numbers may help you to 
>narrow it down somewhat...
   As they pursue this matter, let me urge people to keep in mind the 
question of the "disappearing satellites."  Briefly put, the problem is 
that some objects associated with US classified launches over the past 
seven years or so have vanished somewhat mysteriously.  Based on pre-
disappearance observations, hints and rumors, and a fair amount of 
energetic handwaving, the hypothesis has arisen that they moved to "short 
Molniya" orbits at or near 63 degree inclination, ca. 1000 km perigee 
and apogee in the 5000 to 10000 km range.  Apogee would probably occur 
well into the Northern Hemisphere. 

    Attempts to model observations such as those LTJ and the ETC people 
have made should include some orbits in this category.