Ted Molczan wrote: >The following object passed within about 0.2 of the centre of the lunar disk >about 84 s after the reported time of the transit: According to my calculation, Cosmos 1931 never came closer than 0.8 degree to the center of the lunar disc. This was between 21:21:25 and 21:21:28 UTC. I am using the WGS84 model for the shape of the Earth, and this may explain the discrepancy. Another explanation might be the method to calculate the Moon's position. For this application I am using an algorithm given by Montenbruck/Pfleger in their book "Astronomy on the Personal Computer". I also have the Chapront-Touzé algorithms but I find that the added accuracy does not warrant the increase in calculation time for this kind of problem, the main source of inaccuracy being the TLEs and their evolution and not the motion of the Moon. Bruno Tilgner ----------------------------------------------------------------- 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 : Sat May 05 2001 - 15:46:22 PDT