USA-179 - Orbital Adjustments in the First Half of 2008The major orbital adjustment that would have been the norm in early-January did not happen in the same way as in the past. When the Mean Motion hit its peak value, the downward adjustment was quite small and the Mean Motion kept increasing. The major manoeuvre occurred Feb 8. At this point, USA-179 set three "personal" records since it became operational - the highest value of its Mean Motion ever measured, followed by the biggest drop, and then the lowest value ever measured. The ground track is now somewhat to the east of the earlier operational location. The orbit is in view from the UK when USA-179 is following the Pacific loop of its trajectory. Transmitter switching in now visble across the north pole where it used to occur below the horizon. The new location maintains ground-track synchronisation with USA-137 and USA-198, the newcomer to the constellation. Prior to the recent launch, USA-179's operating companions were USA-137 and USA-125. 2008 February saw two significant retrograde adjustments. One came soon after the Feb 8 major adjustment - interpreted it as a small tweak to correct a small error. The second came Feb 28 but the reason is not obvious.
| |||||||||
