NROL-15 is scheduled for launch from CCAFS on a Delta-IV-Heavy, on 2012 June 29. The launch period is from 09:30 to 14:30 UTC. Lift-off is scheduled for 10:13 UTC. http://www.spaceflightnow.com/delta/d360/status.html The launch azimuth indicates a GEO mission, which for an NRO heavy-lift launch, means the second stage will perform three burns to place the payload directly into an inclined GEO orbit. Below are estimated orbital elements at the end of the three burns. SECO 1 190 X 244 km 1 79501U 12181.43458101 .00000000 00000-0 21234-3 0 09 2 79501 28.7000 253.6000 0040859 90.0000 38.0000 16.22456322 06 SECO 2 212 X 35809 km 1 79501U 12181.44336807 .00000000 00000-0 00000-0 0 03 2 79501 26.5000 253.5314 7298000 180.0000 0.0000 2.28000000 07 SECO 3 35746 X 35830 km 1 79501U 12181.66206019 .00000000 00000-0 00000-0 0 08 2 79501 7.0000 253.4496 0010000 180.1373 179.8600 1.00270000 09 The launch period closely correlates with the 235-275 deg RAAN (right-ascension of ascending node) range associated with nearly all of the inclined GEO SIGINT satellites of Rhyolite lineage, modern-day versions of which we know as Mentor. However, I continue to guess that NROL-15's payload is the third and final first generation Misty, as I explained in April: http://satobs.org/seesat/Apr-2012/0199.html Since then, I have worked on the technical aspects of the problem as time permits. Briefly, I am considering two variations of the Misty hypothesis that may be feasible. The first would result in immediate deployment of Misty into the SECO 1 orbit, after which it would manoeuvre to an an approximately 35 deg, 700 km orbit. The Delta-IV second stage would continue on to GEO, where it would deploy a decoy of perhaps 1500 kg mass into the SECO 3 orbit. Without the RS-68A upgrade, there would be insufficient performance to lift much of a decoy to GEO. The upgraded rocket may have sufficient performance to execute a dog-leg late in the ascent, to increase the SECO 1 inclination a degree or two, which would help Misty reach a higher inclination, at the expense of decoy mass. Whether the fairing could accommodate a decoy (probably housed within a variant of the Sylda5 dual payload adaptor) is an open question; it appears to be a tight fit at best. Could a low-mass decoy be made to appear sufficiently bright to appear to be a heavy SIGINT, with the ability to perform east-west station-keeping for at least 10 years (20 would be better, given the long-life of NRO satellites)? The second variant dispenses with the decoy, and sends nothing to GTO or GEO. The second stage would perform a couple of burns to raise the altitude and inclination of Misty, after which Misty would separate and manoeuvre to further increase its inclination. The second stage would be disposed of in solar orbit. Misty could end up in an approximately 700 km, 45 deg orbit. Without the RS-68A upgrade, Misty's inclination would be limited to well below 40 deg. One challenge with this concept is how best to dispose of Misty's radar-reflective skin. Ideally, it would best be disposed of in the SECO 1 orbit, where they would remain out of range of professional and most hobbyist trackers, before eventually decaying from orbit. That would require disposal prior to separation from the second stage, which may not be feasible. Designing it out probably would be the best solution of all, due to the mass reduction, but that probably would have been impossible if the spacecraft had already been mostly built when it was decided to change the launch profile. Both variants probably require some combination of careful timing and rapid deployment and activation of the optical stealth system, to minimize the risk of detection once Misty manoeuvres to the higher inclination/altitude orbit. Whether that could be achieved with the first generation design is unknown. If nothing new shows up in GEO, then the no-decoy concept will look more attractive. If the second stage and a bright payload show up in GEO, then we will need to decide whether it's an actual SIGINT or a decoy. A high-fidelity decoy may not be immediately distinguishable from an actual SIGINT payload, in which case, I would be left with only my suspicions and proof of nothing. In time, we may be able to determine whether the NRO performed a grand fake-out, or I merely faked myself out. Ted Molczan _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
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