Friday, February 15, 2008

USA 193/NROL-21 Update 2/15/2008

Charles Vick has worked up a drawing of what USA 193/NROL-21 probably looks like. And Charles is noted for being pretty accurate. You can see that image on the Global Security website at

You can learn more about this satellite and the E-305 Radar capability on the Global Security website at USA 193 is believed to be a new generation military radar imaging recon. This Future Imagery Architecture (FIA) Imagery Radar Satellite is probably a replacement for the operational Lacrosse/Vega/Onyx spacecraft that are believed to carrying two elongated radar imaging dishes.

And here is the latest TLE set from Ted Molczan and the SEESAT-L gang.

USA 193 5.0 2.5 0.0 4.3 v 260 X 268 km
1 29651U 06057A 08040.19031987 .00154186 00000-0 23822-3 0 09
2 29651 58.4879 79.7345 0006557 83.6022 276.5824 16.03599602 00
Arc 2008 Feb 04.28 - 09.21, WRMS residuals = 0.039 deg

Mean rate of altitude decrease over the past five days was about 850 m/d (metres per day).

Definition of 2-line elements format:

Using the above elements and a 10.7 cm solar flux of 71, Satevo v0.51 estimates decay from orbit on 2008 March 19, in reasonable agreement with earlier estimates. The uncertainty is at least one week.