Saturday, February 02, 2008

US Spy Satellite USA 193/NROL-21 Update 2/2/2008





Ted Molzcan on the SEESAT group has posted a new element set for this ill-fated American radar imaging spy atellite. Here are updated elements:





USA 193 5.0 2.5 0.0 4.3 v 267 X 275 km
1 29651U 06057A 08032.26673860 .00108121 00000-0 19426-3 0 03
2 29651 58.4892 115.4602 0006491 79.8395 280.3436 16.01043930 04
Arc 2008 Jan 30.29 - Feb 01.29, WRMS residuals = 0.029 deg

Definition of 2-line elements format posted above can be found at http://spaceflight.nasa.gov/realdata/sightings/SSapplications/Post/JavaSSOP/SSOP
_Help/tle_def.html


Using Satevo v0.51 with a 10.7 cm solar flux of 71, results in a decay prediction for USA 193 of March 29, 2008, in line with earlier estimates. The uncertainty is at least one week.

Ted has updated the standard visual magnitude calculation:
http://satobs.org/seesat_ref/06057A/06057A_stdmag_6.jpg

Results are unchanged: mag 4.3 +/- 2, at range 1000 km, phase angle 90 deg. Co-efficient of phase = 1.26 mag/rad (0.0220 mag/deg).

And on a personal note, I am pleased to welcome Ms Angela Gunn, the Tech-Space guru and blooger at USA Today, as a reader of this blog. Thanks for the kind words Angela and keep that hard hat within reach. Now if we can get the Alpha Centaurians to groove out on the Beatles. For more on this tidbit, see my story on the Beatles and space my personal blog - BMP at http://monitor-post.blogspot.com/2008/02/beatles-will-be-beaming-to-polaris.html