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Close Encounters of the Classified Kind

06/09/2017 1:50 PM

A post-event analysis of the close approach of USA 276 to the ISS on June 3.

From SatTrackCam Leiden

Something odd happened a few days ago, high above our heads. In an earlier blogpost, I discussed in detail how the odd spy satellite USA 276 (2017-022A) was set to make a peculiarly close approach to the International Space Station ISS on 3 June 2017. The spy satellite was recently launched for the NRO as NROL-76 by SpaceX, on 1 May 2017.

With the close approach moment now in history and post-approach observations of USA 276 available (as well as an orbit for ISS based on tracking data, rather than an orbital prognosis), I present my final analysis of the situation in the current post.
With the new data included, we can establish the moment of closest approach as 3 June 2017, 14:01:52 UT. It happened over the southern Atlantic north of the Falklands, near 43o.75 S, 45o.45 W, with a miss distance of only 6.4 ± 2 km (the ± 2 km stems from the fact that TLE predicted positions have a typical positional accuracy of no more than 1 km at epoch).

The latter is significantly closer than the approach distances calculated before the approach (which were in the order of 17-20 km, see my earlier post). Ted Molczan also analyzed the situation and he finds an even closer nominal distance of 4.5 km (but within uncertainty intervals our results overlap).

For the ISS, I used elset 17154.48611204. For USA 276, I used the elset below which I calculated based on amateur observations including my own:

more ...

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#1

Re: Close Encounters of the Classified Kind

06/09/2017 2:04 PM

Well, close but, nobody gets the brass ring, or the purple heart either.

I would have thought USAF Intel would have been all over this before the event, however.

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#2
In reply to #1

Re: Close Encounters of the Classified Kind

06/09/2017 2:23 PM

You can be damn sure someone had approval from the top to pull off this stunt. Make no mistake: this was a demo, and what better craft to buzz than one having Russian guests aboard?

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#3
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Re: Close Encounters of the Classified Kind

06/09/2017 2:39 PM

I give you two points for that:

(1) In our control

(2) recent buzzing by Russki aircraft of our B-52 over the Baltic, and other buzzing of USN craft in the Mediterranean Sea.

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#4

Re: Close Encounters of the Classified Kind

06/09/2017 3:09 PM

It sounds like you're suggesting it couldn't have gotten a better shot if aiming for it?? Is it far fetched? Yes.. plausibility?

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#5
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Re: Close Encounters of the Classified Kind

06/09/2017 3:21 PM

You'll have to ask the author.

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#6

Re: Close Encounters of the Classified Kind

06/09/2017 10:01 PM

Now satellite orbits are political????

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#7
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Re: Close Encounters of the Classified Kind

06/10/2017 1:32 AM

Only since the very first one.

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#11
In reply to #6

Re: Close Encounters of the Classified Kind

06/12/2017 10:19 AM

Yes, my friend, we have re entered the cold war with a vengeance and this time we have a new playmate to really keep the game interesting. Russians were pretty predictable, the Chinese, well this should be fun.

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#8

Re: Close Encounters of the Classified Kind

06/11/2017 12:39 PM

So it missed; try harder. Is someone going to get canned for executing a miss?

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#9
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Re: Close Encounters of the Classified Kind

06/11/2017 5:53 PM

After shite landing... w/vpe

" I guess we should have gone around again. .. There goes my career.."

Copilot. "mine too"

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#10

Re: Close Encounters of the Classified Kind

06/12/2017 4:20 AM

One might hope for a better result with Apophys in 2029...

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