Sunday, 1 September 2019

Image from Trump tweet identified as imagery by USA 224, a classified KH-11 ENHANCED CRYSTAL satellite

click to enlarge. image: US Government

The incredibly detailed image above was leaked declassified and revealed to the world by US President Donald Trump, very characteristically in a tweet, on 30 August 2019.

It shows the aftermath of the failed Iranian Safir launch of August 28/29, with considerable damage to the platform and vehicles. Obviously, there was an explosion or crash of some sort, likely an explosion of an engine or rocket stage or failed lift-off.

The image is a photograph of a printed photograph: you can see the reflection of the camera flash on the photographic print near the center of the image and the silhouet of the person photographing it. There is also some image distortion, likely because the print was curling somewhat at the edges. But the level of detail is amazing (and the original might have been even more detailed).

That level of detail quickly led to speculation: what platform took this image? A drone? A high altitude reconnaissance aircraft? A satellite?

Some initially argued that the level of detail was too high for a satellite. But as we will see in this post, it was made by a satellite, and we can even say which satellite.

The level of detail in the image is incredible and points to one of the NRO's classified KH-11 EVOLVED ENHANCED CRYSTAL electro-optical reconnaissance satellites (they are also known as ADVANCED CRYSTAL, KENNEN, and colloquially as 'KeyHole').

These are high resolution optical satellites that resemble the Hubble Space Telescope, but look down to Earth instead of to the heavens. It is known that the optics of these satellites are 2.4-meter diameter mirrors. Theoretically, from the perigee of their orbits this would yield a resolution of just under 10 cm.

Christiaan Triebert analysed the shadow directions on the image and placed the time of the image between 9 and 10 UT (August 29), or 13:30-14:30 local Iranian time. Michael Thompson pointed out on Twitter that one of the KH-11 satellites, USA 224 (2011-002A), made a pass over the launch site in that time window.

This satellite is a classified satellite, but we do know its orbit because amateur trackers track this object regularly. This is USA 224 passing over my hometown Leiden in June 2014 for example:

USA 224 passing over Leiden, 21 June 2014

This blogpost consolidates two analysis which I initially published through Twitter. I will show in this analysis that there is very little doubt that USA 224 took this image.

Matching view angles 

The map below shows how USA 224 passed almost right over the launch site at 9:43:47 UT on August 29, with a maximum elevation of 87.7 degrees. The photograph tweeted by President Trump was taken post culmination, from the location indicated by the white cross in the map above. That position is based on the analysis that now follows.

click map to enlarge

The depicted trajectory for USA 224 is based on amateur tracking data. I used elset 19239.00965638 which was ~2.5 days old at the time of the overflight. In the absence of a manoeuvre, it should be accurate to a few seconds in time along-track and very little error cross-track.

USA 224
1 37348U 11002A   19239.00965638 0.00010600  00000-0  95384-4 0    03
2 37348  97.9000 349.1166 0536016 134.6567 225.3431 14.78336728    04

The imaged launch site itself is located at 35.2346 N, 53.9210 E, altitude 936 m, and indicated by the blue dot in the map. The launch platform is part of Iran's Imam Khomeini Space Port, near Semnan.

click to enlarge. Image: US Government

Trump's image shows the platform viewed under an oblique angle, looking in a northern direction (i.e. with the satellite to the south of the site). As the launch platform is circular, we can use the ellipticity of the platform on the image to estimate the angle under which the platform was imaged. For this, we have to measure the semi-minor and semi-major axis of the ellipse (denoted Y and R in the diagram below): their ratio corresponds to the sinus of the viewing angle.

The result of this measurement is a nominal view angle of 46.03 degrees. For USA 224, this elevation with respect to the imaged site was reached at 09:44:20.7 UT (nominally), post-culmination when the satellite was to the south of the site. From the satellite ephemeris, the satellite was at an azimuth of 194.85 degrees as seen from the imaged site at that moment. The satellite's geographical position was near 33.005 N,  53.220 E at an altitude of  283 km. The range to the imaged site was 385 km.

I used these values as input in STK and simulated the view of the damaged launch platform as seen from USA 224 for 29 August 09:44:20.7 UT. The images below compare the original image from President Trump's tweet (top) and the simulated view from USA 224 (bottom):

click to enlarge

Ignoring the shadow directions, the simulated view is very similar to the actual image, pointing out that indeed the image very likely was taken by the USA 224 satellite.

(the simulated view uses an overhead commercial satellite image taken at another time, rendered to mimic an oblique view, hence the different shadow directions).

Cees Bassa, in an independent analysis, has calculated very similar figures for the viewing angle and from that azimuth and elevation.

Matching times

In a second analysis, I tried to improve on the time of the image derived from the shadow directions.

When projecting a line through the shadow of one of the masts at the edge of the platform, this line passes almost through the middle of the access road at top right in the image:

click to enlarge

I used this observation to measure the direction of the shadow in Google Earth. It corresponds to an approximate azimuth of 40.45 degrees, which would place the sun at an azimuth of about 220.45 degrees (+- 1 degree error or so):

click to enlarge

Looking this direction up in the solar ephemerids for the imaged site (calculated with MICA), this solar azimuth corresponds to 09:46:25 UT (Aug 29). This is only 2 minutes later than the time for which the image best matches the USA 224 view of the site, as reconstructed earlier in this post.

This again confirms that this image could very well have been taken by USA 224. Both the time matches, and the view matches.

With the uncertainties in the shadow direction measurement taken into account (including uncertainties introduced by possible image deformations), within error margins the two times match. The difference between the measured (~220.45) solar azimuth and the solar azimuth calculated for 09:44:21 UT is 0.85 degrees, i.e. under a degree and hence small.

The 09:44:21 UT  derived from matching the satellite view to the image, probably is more accurate than the time derived from the shadow analysis. This time is probably accurate to a few seconds, given that the satellite TLE used was 2.5 days old.


And then the baffling question: why did President Trump tweet an image that otherwise would be considered highly classified?

The KH-11 satellites are classified, and so is imagery from these satellites. If an adversary gets her hands on KH-11 imagery, it reveals information about the optical capacities of these space assets.

In 1984, a Navy intelligence analyst was sent to prison for leaking three KH-11 images to the press.

Reconnaissance satellite imagery made public by the US Government itself over the past decades were either from commercial DigitalGlobe satellites, or purposely degraded in quality such as not to reveal the optical capacities of the KH-11. But now we see a US President tweet, on what appears to be a whim for the purpose of gloating, a very detailed image that as was shown in this post definitely was taken by a KH-11 satellite.

The occassion at which this happened, is eyebrow raising. A failed space launch hardly is a matter of great geopolitical concern. It is something trivial compared to e.g. imagery showing preparations for an invasion, the production of WMD, or atrocities against humanity. The latter could perhaps be argued to be a valid reason to publish imagery that also divulges the capacities of your best space-based imaging platforms: this occasion was not.

Which makes this a rather momentous occasion.

(note: there is a black block in the upper left of the image that seems to be placed there to redact some information that might have been printed there. I think it is likely this information was the time of image, space platform ID and the location of the latter. It points out that some deliberate thought was given to the release of this image, before it was tweeted).

USA 224 passing through Corona Borealis, 17 June 2014

Edit (2 Sep 2019):

In the comments, Russ Calvert makes a very valid point: the phone camera used to photograph the photographic print might also introduce some slant. But I suspect the error introduced this way is small as normally you would try as best as you can to hold the camera perpendicular to the paper you are photographing. A clear slant angle of the camera also would introduce a sharpness gradient that does not seem to be there. The good match between the image and the simulated view from the satellite also bears out that error introduced in this way is likely small.

Edit II (2 Sep 2019):

Added two archive images of USA 224 passing through the night sky over my hometown Leiden.