Re: NROL-82: targeting sun-synchronous orbit

From: Marco Langbroek via Seesat-l <seesat-l_at_satobs.org>
Date: Tue, 13 Apr 2021 15:38:00 +0200
Op 12-4-2021 om 19:00 schreef C. Bassa via Seesat-l:
> The NRO just posted a tweet indicating that NROL-82 "is targeted for
> no-earlier-than April 25, 12:39-15:57PDT".
> https://twitter.com/NatReconOfc/status/1381648189267271680
> 
> This launch window correspond to 19:39 to 22:57UTC, and for a
> sun-synchronous is consistent with the Eastern plane of KH-11
> satellites, currently occupied by only USA 224 [37348/11002A].


[note: April 25 above in Cees' mail should read April 26!]

This is interesting. If the USA 224 plane is indeed targetted, I expect launch
near 21:00 - 21:30 UTC.

The orbital plane of USA 224 passes over Vandenberg LC-6 at 21:20 UT (April 26).
In 2011, USA 224 was launched some 20 minutes before the orbital plane of it's
predecessor USA 161 passed over the launch site.

We can then also expect, if it follows historic KH-11 constellation patterns
(see
https://sattrackcam.blogspot.com/2013/09/past-and-future-of-kh-11-keyholeevolved.html),
that after insertion of NROL-82 into the KH-11 primary East plane and a period
of checkout, USA 224 currently occupying that plane will be moved to a plane
10-20 degrees more eastwards (the secondary East plane) and lower it's apogee
considerably, to near ~400 km.

By the way: if we indeed see this return to the historic KH-11 orbital
constellation, then this also strongly begs the question what USA 290
(2019-004A) is.

USA 290 was thought to be a KH-11 by analysts but surprisingly went into an
unexpected, distinctly non- KH-11 orbit. It is non-polar (73.6 degrees
inclined), non Sun-Synchronous, and unlike what you expect for a KH-11 or indeed
any IMINT mission. The identification as a KH-11 therefore never has been
sitting well with me.

If NROL-82 goes into an old-fashioned KH-11 orbit again, then I am more and more
convinced that USA 290 is not a KH-11.

- Marco



-----
Dr Marco Langbroek  -  SatTrackCam Leiden, the Netherlands.
e-mail: sattrackcam_at_langbroek.org

launchtower:    http://launchtower.langbroek.org
Station (b)log: http://sattrackcam.blogspot.com
Twitter:        _at_Marco_Langbroek
-----


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Received on Tue Apr 13 2021 - 08:38:46 UTC

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