At 15:55 10/05/00 , Ed Cannon wrote: >Below are a couple of online sites. The first one >purports to do the conversion in either direction, from >state vector to TLE or vice versa. > >"The applet below allows conversions between orbit >elements and state vectors.": >http://alpha.fesg.tu-muenchen.de/dieter/java/TLOrbit.html > >"Transform from orbital elements to state vector" >http://www.geocities.com/SiliconValley/2902/ele2vec.htm > Ed, I think both of these sites just use the two-body formulation of the conversion. If one used them to go ftom state vector to elements, one will get the osculating elements, not mean elements like the SPG4, SPD4 element sets in TLEs. This means these sites are OK for solar system calculations, but not of much practical use for earth satellite prediction, but may be useful for satellite orbit design studies. Thus there use is not the same as converting TLE's to position and velocity, which i understand the query was about. To go from TLE's to state vector one should follow the formulae given in the spacetrack documentation, or copy the code from a publicly available source code, like TS Kelso's example programme, TRAKSTAR. Tony Beresford ----------------------------------------------------------------- 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 : Wed May 10 2000 - 23:54:53 PDT