NOSS 3-3 (A) 0.0 0.0 0.0 4.0 v 1 28537U 05004A 05071.85691448 .00000011 00000-0 20000-4 0 03 2 28537 63.4359 66.8198 0128055 179.5464 180.5699 13.39754399 03 Arc 2005 Mar 03.83 - 12.87, WRMS residuals = 0.027 deg NOSS 3-3 (C) 0.0 0.0 0.0 4.0 v 1 28541U 05004C 05071.85700506 .00000011 00000-0 20000-4 0 04 2 28541 63.4372 67.0105 0128275 179.3702 180.7507 13.39754976 02 Arc 2005 Mar 08.99 - 12.88, WRMS residuals = 0.022 deg NOSS 3-3 r 0.0 0.0 0.0 4.7 v 1 28538U 05004B 05071.84923411 .00000030 00000-0 50000-4 0 05 2 28538 63.8239 68.1460 0136307 175.2018 185.0354 13.42846713 03 Arc 2005 Mar 07.14 - 12.87, WRMS residuals = 0.020 deg Description of 2-line elements: http://www.satobs.org/element.html I no longer believe that 05004C raised its orbit between the observations of 2005 Mar 09 at 10:55 UTC, and Mar 10 at 12:00 UTC; therefore, I have reinstated the earlier arc starting date/time that I used previously. It will be interesting to see how long the payloads cruise at their present mean motion before manoeuvring to match that of the other operational groups, near 13.40465 rev/d. Perhaps the upper limit could be deduced by the date at which the nearly coplanar 91076C,D,E group would overtake 05004A,C. As of the above epoch, their node crossings trailed those of 05004A,C by 2197 s, closing at the rate of about 45.8 s/d, which puts the overtaking date about 48 d later, or about Apr 29. Presumably, optimal spacing would not have the these groups above the horizon at the same time, so the manoeuvre to station-keep should come well before or after that date. Another possibility is for 05004A,C to manoeuvre to an intermediate cruising mean motion, and remain there for some time, before their final manoeuvre to station-keep. As I noted in an earlier post, the NOSS 3-1 and 3-2 groups cruised for several months at a temporary mean motion within approx +/- 0.0015 rev/d of the operational mean motion. Regardless of when it is achieved, any station-keeping with 91076C,D,E will be in time only, because 91076C,D,E's plane will drift nearly 0.009 deg/d west relative 05004A,C's. Ted Molczan ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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