"Björn Gimle" wrote: > > "...J002E3 Elements in TLE form: > 1 99999U 99999A 03 84.00000000 -.00000000 +00000-0 +00000-0 0 00010 > 2 99999 25.3923 10.1760 3728026 257.3057 298.1392 0.01771572000007 > > .... > > SkyMap gives from Earth Centre at 30 Mar 00 UT 13:28 -5 32' range 474280 > km For a geocentric observer Horizons gives: 2003-Mar-30 00:00 13 31 58.26 -06 05 03.3 13 32 08.66 -06 06 07.1 Range converted from AUs, 480801 km. First RA/Dec pair is ICRF/J2000.0 with which I'm quite happy. Second is "a-apparent". What does this mean and why is it different? I turned off refraction correction so the difference is not just that. (Refraction correction seemed a bit pointless with 6000+km of rock in the way. :-) Is it due to nutation, etc: i.e., relative to the ITRF (terrestrial reference frame) rather than celestial? I forwarded John Holtz's message to somebody with a decent tele- scope and a web-cam modded for long exposures a few days ago when it looked possible that a front might clear the air here in south eastern England but actually we've gone from high pressure haze to quite heavy mist so I'm not too hopeful of him getting any piccies. Ed Davies. ----------------------------------------------------------------- To unsubscribe from SeeSat-L, send a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@satobs.org List archived at http://www.satobs.org/seesat/seesatindex.html
This archive was generated by hypermail 2b29 : Sat Mar 29 2003 - 19:37:23 EST