Tony Beresford, David Brierley and Russell Eberst have reported new observations. The object was more than half a minute early relative my three day old elements, due to an increase in geomagnetic activity during Feb 1 to 3, which sometimes reached storm level: http://www.swpc.noaa.gov/ftpdir/indices/DGD.txt This is reflected in the updated elements by a 50 percent increase in rate of decay: USA 193 5.0 2.5 0.0 4.3 v 264 X 273 km 1 29651U 06057A 08035.26297568 .00167697 00000-0 28374-3 0 08 2 29651 58.4890 101.9619 0006774 80.4195 279.7669 16.02067677 05 Arc 2008 Jan 31.29 - Feb 04.28, WRMS residuals = 0.029 deg Definition of 2-line elements format: http://spaceflight.nasa.gov/realdata/sightings/SSapplications/Post/JavaSSOP/SSOP _Help/tle_def.html Geomagnetic activity has since subsided; therefore, the above rate of decay probably is overstated for prediction purposes, which will result in the object running late. Using the above elements, but with a guessed lower rate of decay going forward (ndot/2 = 0.0012), and a 10.7 cm solar flux of 71, Satevo v0.51 estimates decay from orbit on 2008 March 26, in line with earlier estimates. The uncertainty is at least one week. Ted Molczan ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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