The US Department of Defense has issued a couple of NOTAMs out of the Honolulu ARTCC that may indicate when the US Navy is going to attempt a shootdown of the NRO Spy Satellite USA 193. The USS Lake Erie CG-70 and USS Decatur DDG-73 are set to perform the mission using the Navy has modified three SM-3 missiles aboard Aegis ships to strike the satellite, said Marine Gen. James E. Cartwright, vice chairman of the Joint Chiefs of Staff.The Navy wants to intercept the satellite at a point just above the atmosphere so there would be a high likelihood of bringing it down in an unpopulated area. An intercept also would rupture the hydrazine tank. The vice chairman would not say exactly where the ships would fire from, only saying it will be from the northern hemisphere and the Pacific Ocean.
The first operational opportunity is detailed in this NOTAM:
02/062 (A0038/08) - AIRSPACE CARF NR. 90 ON EVELYN STATIONARY RESERVATION WITHIN AN AREA BNDD BY 3145N 17012W 2824N 16642W 2352N 16317W 1909N 16129W 1241N 16129W 1239N 16532W 1842N 17057W 2031N 17230W 2703N 17206W SFC-UNL. 21 FEB 02:30 2008 UNTIL 21 FEB 05:00 2008. CREATED: 18 FEB 12:51 2008
Based on this NOTAM the shootdown will occur on 21 Feb 2008 between 0230-0500 UTC or 20 feb 2008, Wednesday evening 2130-2400 EST.
Using the NOTAM above and the latest TLE Ted Molzcan has plotted a possible shootdown scenario and placed that into a PDF at http://satobs.org/seesat_ref/06057A/USA_193_NOTAM_unverified.pdf.
That diagram is also presented below. Looks like the actual first shootdown attempt of USA 193 will occur around 21 Feb 2008 at 0330 UTC (20 Feb 2008 2230 EST).
USA 193 Shootdown plot courtesy of Ted Mozcan and the SEESAT-L newsgroup.The benefit of a shootdown during this pass, is that if anything does come down, it will do so over the barren Canadian Arctic rather than over populated area. You can see that track on a satplot displayed on Dr. Marco Langbroek satrackcam blog at
http://sattrackcam.blogspot.com/2008/01/usa-193-imminent-decay-in-news.html.
Our good friend John Locker has just passed along a second NOTAM that I have reposted below.
02/067 (A0708/08) - AIRSPACE STATIONARY RESERVATION WITHIN AN AREA BNDD BY 3145N / 17012W, 2824N / 16642W, 2352N / 16317W, 1909N / 16129W, 1241N / 16129W, 1239N / 16532W, 1842N / 17057W, 2031N / 17230W, 2703N / 17206W SFC-UNL. 22 FEB 02:30 2008 UNTIL 22 FEB 05:00 2008. CREATED: 19 FEB 12:30 2008
This is exactly 24 hours later than the first attempt. So based on this NOTAM the 2nd attempt at a USA 193 shootdown will occur on 22 Feb 2008 between 0230-0500 UTC or 21 Feb 2008, Thursday evening 2130-2400 EST if the first attempt is not successful.
For visual observers the latest TLE elset from Ted Molzcan and the SEESAT-L group follows:
USA 193 5.0 2.5 0.0 4.3 v 250 X 257 km
1 29651U 06057A 08049.03290930 .00227439 00000-0 27958-3 0 02
2 29651 58.5131 39.7259 0005095 99.1484 261.0195 16.07330305 09
Arc 2008 Feb 11.46 - 18.04, WRMS residuals = 0.1 deg
Rate of altitude decrease is about 1.3 km/d (kilometres per day).Using the above elements and a 10.7 cm solar flux of 70, Satevo v0.51 estimatesdecay from orbit on 2008 March 15. The uncertainty is at least several days.Definition of 2-line elements format:http://spaceflight.nasa.gov/realdata/sightings/SSapplications/Post/JavaSSOP/SSOP