The original work on this was performed in 1995 by Rainer Kracht, using Russell Eberst's observations available at that time: http://www.satobs.org/seesat/Dec-1995/0034.html I have updated the analysis, using Russell's observations to date: NOSS 2-1 (C) 1990-050C 20691 309 5.82 0.0244 NOSS 2-1 (D) 1990-050D 20692 336 5.85 0.0246 NOSS 2-1 (E) 1990-050E 20642 185 5.47 0.0166 NOSS 2-2 (C) 1991-076C 21799 333 5.72 0.0254 NOSS 2-2 (D) 1991-076D 21808 333 5.75 0.0257 NOSS 2-2 (E) 1991-076E 21809 210 5.68 0.0238 NOSS 2-3 (C) 1996-029C 23908 98 5.86 0.0197 NOSS 2-3 (D) 1996-029D 23862 91 5.77 0.0173 NOSS 2-3 (E) 1996-029E 23936 80 5.69 0.0180 ------------------------------------------------------ ALL 1975 5.74 0.0231 column 1 : name column 2 : international designation * column 3 : catalogue number * column 4 : number of observations column 5 : standard magnitude, 1000 km range, 90 deg phase angle column 6 : phase coefficient, magnitude per degree * note that in the absence of official information, hobbyists have agreed on a naming convention that designates objects according to their location with each triad, in order of leader, trailer and outlier. Those locations could change over time. I believe that my methodology is similar to Rainer's, in that we determined the range of each observation and used that information to compute the equivalent magnitude at a range of 1000 km, according to the inverse-square law. Finally, we correlated 1000 km magnitude with phase angle. One small difference in methodology: Rainer used pairs of observations on the same pass to compute an approximate circular orbit, from which he computed the range of each observation. I used the available elements, on the basis of epoch nearest time of observation. The advantage of Rainer's method is that it does not depend on knowledge of the elements, while maintaining high accuracy, even with moderately eccentric orbits (like KeyHoles). The advantage of my method is that it does not require pairs of observations, thus increasing the number of usable observations. Ted Molczan ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www.satellite.eu.org/seesat/seesatindex.html
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