NROL-39 search elements

From: Ted Molczan (
Date: Tue Dec 03 2013 - 14:07:24 UTC

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    NROL-39 will launch FIA Radar 3 (aka Topaz 3) on an Atlas V-501, from Vandenberg AFB, on 2013 Dec 06, at 07:13 UTC. The
    duration of the launch window has not been made public.
    That the codename of the FIA Radar series is Topaz was revealed in budget documents leaked by Edward Snowden, which
    indicated that five (5) spacecraft are planned, to be succeeded eventually by Topaz Block 2, for which spending was to
    begin in U.S. FY2013.
    Listed below are the historic and planned FIA Radar Block 1 launches.
    NROL-41  FIA Radar 1  Atlas V-501      10046A 37162  
    NROL-25  FIA Radar 2  Delta IVM+(5,2)  12014A 38109  
    NROL-39  FIA Radar 3  Atlas V-501
    NROL-45  FIA Radar 4  Atlas V-501
    NROL-??  FIA Radar 5  Delta IVM+(5,2)
    Those following NROL-39 are guesses. I am highly confident in NROL-45, since it was purchased together with NROL-41, 25
    and 39. All four launches have been long-delayed past their original planned launch dates, due to problems building the
    first spacecraft. That the fifth launch will employ a Delta IVM+(5,2) is a guess, based on the facts that one was used
    on NROL-25 for FIA Radar 2, and another was included in a recent EELV purchase, for use by the NRO: 
    The launch number and site of the newly procured vehicle were not specified, but I expect VAFB will eventually be
    revealed to be the launch site, which will almost certainly make the payload FIA Radar 5. The FIA Radar orbit can only
    be reached by launching from the west coast.
    I estimated the search TLEs based on the initial orbit of NROL-41 (FIA Radar 1), since it employed the same launch
    vehicle as NROL-39 (Atlas V-501). The initial orbit of NROL-25 (FIA Radar 2) was a bit higher, which I assume was due to
    the use of the Delta IVM+(5,2).
    Launch at 07:13 UTC would result in the following orbit:
    07:13 UTC launch                                      1067 X 1080 UTC
    1 78802U          13340.34639405  .00000000  00000-0  00000-0 0    03
    2 78802 122.9957 219.8171 0008930  69.2445 290.9476 13.49595610    01
    In the event that the orbit proves similar to that of FIA Radar 2, then the object will trail the above elements by
    about 2 min on the first pass over North America, and fall farther behind by about 20 s per rev.
    A couple of weeks ago, Cees Bassa reminded me that the first two FIA Radar orbits are almost precisely 180 deg apart in
    RAAN. Cees suggested that the present launch might target a plane midway between them. The above orbit falls reasonably
    close to that separation. Delaying the launch to 07:36 UTC would place the new orbit exactly midway between the first
    two in RAAN, with the following approximate elements:
    07:36 UTC launch                                      1067 X 1080 UTC
    1 78801U          13340.36236899  .00000000  00000-0  00000-0 0    04
    2 78801 122.9957 225.5838 0008930  69.2445 290.9476 13.49595610    04
    I expect the launch to occur at 7:13 UTC, but would not be shocked should it mysteriously slip to ~07:36 UTC.
    The above orbits would result in visible passes in the morning for northern hemisphere observers, and evening for those
    in the southern hemisphere.
    Soon after the first two launches in the series, the second stage was de-orbited into the Indian Ocean. NROL-39 carries
    secondary payloads, which may result in the second stage remaining in orbit. A re-entry hazard notification has yet to
    appear among the Broadcast Warnings.
    Observers in the North Eastern part of North America may be able to observe the primary payload and its Centaur on their
    first pass over that continent. Based on the 78802 orbit, visibility will be cut short by entry into eclipse at about
    08:43 UTC. From my location (Toronto) they should reach 21 deg elevation prior to eclipse, with a reasonably good solar
    illumination. Observers north and east of me will have a better view. 
    Kevin Fetter and I were clouded-out in our attempts to make this observation after the FIA Radar 2 launch, in April
    2012. Had the weather co-operated, we would have seen venting from the Delta IV 2nd stage, as evidenced by UFO sightings
    from Northern Ontario, Pennsylvania, Virginia and West Virginia, which Tim Printy correlated with the initial FIA Radar
    2 orbit and venting from 2nd stage, as reported in the July-August 2013 edition of his SUNlite publication (see pg.14,
    Canadian Unknowns identified):
    Given the difference in launch vehicles and the presence of secondary payloads, it is unclear what to expect of
    NROL-39's first North American pass, but observing the proximity of the Centaur to its primary payload, as well as any
    signs of manoeuvring by the Centaur, may assist in estimating the orbit of the secondary payloads and the final orbit of
    the Centaur.
    Ted Molczan
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