Robert Fenske wrote: > Yes I believe its standard magnitude is too bright. I > tried naked > eye observations of it last summer and never saw it. I > reported such in > the message > http://www2.satellite.eu.org/seesat/Jun-1999/0077.html. I > haven't looked for it since then so I don't have an idea of > how bright it > really is, though I suppose if it's the same kind of rocket > as the others > (#19468 and #20791) its standard mag should be around 6 (not 3.5). This discussion has prompted me to review my data. My software had estimated the standard magnitude at 6.2, based upon the object's dimensions at launch; however, it broke up soon after launch. Judging by its RCS of 10.4 m^2, the D piece must be quite a large chunk of the original rocket. I have searched Russell Eberst's observations, and found six since Nov'96. Though it is a small data set, it is fairly consistent, and indicates a std magnitude of 6.6. Using this value, the greatest deviation between Russell's observations and prediction was only 0.4 magnitudes. Here is a recent elset with the observation-based std mag: Feng Yun 1-2 r 1.9 2.9 0.0 6.6 v 10.4 1 20791U 90081D 00096.90782038 .00000371 00000-0 32191-3 0 3443 2 20791 99.1348 57.9592 0053894 144.8041 215.6705 13.91831558487226 Ted Molczan ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www2.satellite.eu.org/seesat/seesatindex.html
This archive was generated by hypermail 2b29 : Fri Apr 14 2000 - 08:34:06 PDT