Ralph McConahy wrote: > Using this TLE from the NASA ISS web site: > > ISS > 1 25544U 98067A 03105.53106156 .00041100 00000-0 34010-3 0 9050 > 2 25544 51.6352 334.9570 0006812 21.4703 338.6736 15.58205811 11238 > > The ISS will indeed cross the Sun's disk, but about 9-seconds > earlier than you predict (17:35:57 UT). Those elements are now out of date, which explains the 9 s difference. These two are now the closest ones to the time of the transit on the ISS site: http://spaceflight.nasa.gov/realdata/sightings/SSapplications/Post/JavaSSOP/or bit/ISS/SVPOST.html 1 25544U 98067A 03105.27461242 .00041100 00000-0 34010-3 0 9017 2 25544 51.6329 336.2421 0006040 22.0682 338.0732 15.58140717 11196 1 25544U 98067A 03106.30077509 .00041100 00000-0 34010-3 0 9022 2 25544 51.6329 331.0947 0006072 25.1974 334.9476 15.58180419 11356 Or, you can use the latest USSTRATCOM product, issued via NASA/OIG: 1 25544U 98067A 03104.78447162 .00011195 00000-0 15207-3 0 8924 2 25544 51.6336 338.6980 0006712 19.3333 109.6182 15.58131185251116 Note that the elsets on the ISS site are accurate conversions from the ISS Flight Dynamics Officer's predicted elements - except for the decay terms - which are almost never updated. As long as you use an elset within a day or so of the event, the error will be small. Ted Molczan ----------------------------------------------------------------- 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 : Mon Apr 14 2003 - 19:11:42 EDT