NROL-34 is scheduled for launch on an Atlas V-411, from VAFB, on 2011 Apr 15 at 04:24 UTC.
The target orbit appears to be NOSS (Naval Ocean Surveillance System). If it is another 3rd generation NOSS launch, then
the payload would consist of two satellites that would orbit in close formation.
The Centaur will be de-orbited within one rev of launch; its debris footprint is centred near 45 S, 104 W; time of
impact would be roughly 06:40 UTC.
Assuming the same trajectory as the previous NOSS launch from VAFB (Dec 2003, Atlas 2AS), the initial orbit would be as
follows (epoch is that of the first ascending node):
1010 X 1202 km
1 79934U 11105.23337441 .00000000 00000-0 00000-0 0 00
2 79934 63.4238 350.7625 0128090 179.8595 180.2488 13.40628235 07
The plane is not close to that of any existing operational NOSS formation.
I have not analyzed visibility windows in detail, but it appears that Northern hemisphere observers would have evening
visibility; southern hemisphere observers would have marginal pre-dawn passes.
I had expected this to be another SIGINT payload headed for a Molniya orbit, like that of NROL-28, which also launched
from VAFB on an Atlas V-411. For a NOSS 3 launch, the Atlas V-401 appeared to have plenty of performance, so the use of
the larger rocket is a bit of mystery. I offer the following guesses for discussion:
1. The June 2007 NROL-30 launch of NOSS 3-4 from CCAFS on an Atlas V-401, left both satellites in too low an orbit,
after a failed valve caused some of the Centaur's hydrogen to leak out. The spacecraft used their thrusters to make up
the shortfall, but it was a close call. Could the experience have prompted the NRO to opt for a higher performing rocket
for future launches? Seems unnecessary if the present valves are reliable, but I throw it out for discussion. Here is a
report on the mishap.
http://www.spaceflightnow.com/news/n0708/16rl10valve/
2. The Atlas V-411 appears to have sufficient performance to launch three NOSS 3 satellites. Two could establish a new
operational plane; the third could replace an ailing satellite in one of the other existing planes (altering its
altitude and/or inclination slightly from the standard NOSS values would enable its plane to drift toward the other
target plane). I do not know whether the fairing could accommodate a third NOSS 3.
3. It will launch a secondary payload unrelated to NOSS - perhaps a replacement of the developmental USA 193 (aka 06057A
/29651 / NROL-21) satellite that failed upon reaching orbit in Dec 2006. A pair of NOSS 3 (~3000 kg each) plus the
approximately 2300 kg USA 193 are within the performance capability of the Atlas V-411 to a NOSS orbit. I do not know
whether the 58.5 deg, 360 km USA 193 orbit could be accommodated on the same launch as a NOSS, nor do I know whether all
three spacecraft would fit within the fairing. Seems like a long shot.
4. It is the first launch of a fourth generation NOSS, more massive than the third generation NOSS.
5. It is something completely new, unrelated to NOSS, headed into a quasi-60 deg orbit of unknown altitude.
Ted Molczan
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