Delay to Dec 7th: https://twitter.com/NatReconOfc/status/1065273975381594114
Does this have anything to do with SSO-A slipping to the 27th?
Patch-ology:Significance of the initials on the bald eagle's two dog-tags? I noted they were whited out in the image up-thread with the original Klingon phrase.
Noted from reading the writings and postings of several satellite observing boffins/analysts:All (deduced) KH-11 launches have been from Vandenberg.Amateur satellite observers have observed that all successful launches for KH-11's result in two different polar (sun-synchronous?) destination orbits labelled East and West.All "west" satellites have launched between 18:00 and 18:30 UTC.All "east" satellites have launched between 21:10 and 21:35 UTC.Some questions/thoughts:Will the launch window for NROL-71, when announced, conform to the previous pattern of strict duality?
unusuallaunch 08:19 PM PST ---> 04:19 UTC (?)https://www.ulalaunch.com/missions/delta-iv-nrol-71
This launch would be the first of the KH-11's on a Delta IV-H upgraded. Will the extra "performance" allow a greater breadth in launch time around the optimal, assuming other parameters are unchanged, such as payload mass and initial orbit?
So the plot thickens. Ted Molczan has posted a plot of the hazard areas on SeeSat-L (http://www.satobs.org/seesat/Dec-2018/0014.html) and it appears that the target inclination is about 74 degrees! That this is not going to sun-synchronous orbit is unusual to say the least.The USSR did operate Zenit photoreconnaissance satellites in similar orbits (up to about 73 degrees) but these launches ended in the 1980s and there were also a very small number of Corona satellites that used a 75-degree orbit in the 1960s. Russia has also used this inclination for ELINT satellites, but DIVH would seem like overkill for an ELINT bird.I am considering three possibilities: * A KH-11 or successor targeting a different inclination * A Misty/USA-144 follow-on (either operating in a 74 degree orbit, or manoeuvring to ~63 degrees) * Something completely different
Quote from: William Graham on 12/04/2018 09:41 pmSo the plot thickens. Ted Molczan has posted a plot of the hazard areas on SeeSat-L (http://www.satobs.org/seesat/Dec-2018/0014.html) and it appears that the target inclination is about 74 degrees! That this is not going to sun-synchronous orbit is unusual to say the least.The USSR did operate Zenit photoreconnaissance satellites in similar orbits (up to about 73 degrees) but these launches ended in the 1980s and there were also a very small number of Corona satellites that used a 75-degree orbit in the 1960s. Russia has also used this inclination for ELINT satellites, but DIVH would seem like overkill for an ELINT bird.I am considering three possibilities: * A KH-11 or successor targeting a different inclination * A Misty/USA-144 follow-on (either operating in a 74 degree orbit, or manoeuvring to ~63 degrees) * Something completely differentCould it be that is being deliberately launched into this orbit to hide its purpose and then manoeuvre into a more typical orbit after launch or would that kind of change require the use of too much propellant.
Quote from: Star One on 12/05/2018 10:37 amCould it be that is being deliberately launched into this orbit to hide its purpose and then manoeuvre into a more typical orbit after launch or would that kind of change require the use of too much propellant.From a very quick approximation, I think the Delta-V requirement would be somewhere on the order of 3km/s, which does seem excessively high - especially for a satellite the size of KH-11. This is assuming a 1,200 km circular orbit inclination change from of 74 to 98 degrees - in reality the perigee is likely to be lower, resulting in a greater Delta-V requirement.My earlier suggestion of a change to 63 degrees (the orbit previously used by MISTY) would be about half of the Delta-V to SSO, but that still seems too high to be likely, so I suspect the final orbit will be closer to 74 degrees (although it could still manoeuvre by a few degrees).I'd appreciate if someone could check my figures.
Could it be that is being deliberately launched into this orbit to hide its purpose and then manoeuvre into a more typical orbit after launch or would that kind of change require the use of too much propellant.
Could this KH-11 be a very different beast to its predecessors, perhaps smaller with the use of electric propulsion. I remember reading several articles over the past years where the NRO indicated that they wanted to use smaller satellites than in the past.
Quote from: Star One on 12/06/2018 03:08 pmCould this KH-11 be a very different beast to its predecessors, perhaps smaller with the use of electric propulsion. I remember reading several articles over the past years where the NRO indicated that they wanted to use smaller satellites than in the past.Yes but why launch it into a 74° orbit even if it has high delta-v? Unless it is stealthy, foreign countries and amateurs will be able to track it anyway.
