USA 338, the NROL-91 payload, observed

NROL-91. Click image to enlarge

On 24 September 2022 at 22:25:30 UT, with half an hour delay, ULA launched NROL-91, a Delta IV Heavy with a classified payload for the NRO. The payload is probably an electro-optical reconnaissance satellite in the KH-11 lineage (for more backgrounds see the previous post).

Six hours after the launch, the payload, USA 338, made a pass over the Netherlands and around 4:17 UTC (6:17 local time) was observed by Cees Bassa from Dwingeloo and by me from Leiden. It was visible by the naked eye with a brightness around magnitude +2.5 to +3.

The image above shows it ascending over the roof of my house, passing close to the Hyades cluster in Taurus. The image was taken with a Canon EOS 80D + Samyang 1.4/35 mm lens, 5 seconds at ISO 800. The sky was clear but with sacttered clouds, as can be seen in the image.

A very preliminary orbit fit suggests a 73.59 degree inclined, 376 x 415 km orbit. The RAAN difference with USA 290, an earlier launch of similar type, is ~99 degrees. When the orbit gets better established, these figures might still change somewhat.

 

NROL-91: a new (possibly electro-optical) sister ship of USA 290

 

click map to enlarge

On 24 September 2022 at 21:53 UT, an ULA Atlas Delta IV Heavy (the last to be launched from Vandenberg) will launch from Vandenberg SFB Launch Complex 6 as NROL-91, carrying a classified payload into Low Earth Orbit for the NRO.

The launch is in southernly direction. The locations of the four hazard areas from the published Navigational Warnings (see map above and text below) are consistent with launch into an orbital inclination of 73.6 degrees, which is similar to NROL-71 from January 2019 that launched USA 290 (2019-004A). 

So the NROL-91 payload likely is a sister ship to USA 290.

Below is Navigational Warning HYDROPAC 2592/22 for the launch (note that there appears to be a clerical error in the first coordinate of area C):

122224Z SEP 22
HYDROPAC 2592/22(GEN).
EASTERN PACIFIC.
CALIFORNIA.
1. HAZARDOUS OPERATIONS:
   A. 242020Z TO 242347Z SEP, ALTERNATE
      2020Z TO 2347Z DAILY 25 THRU 27 SEP
      IN AREA BOUND BY
      33-53.00N 120-23.00W, 34-28.00N 120-40.00W,
      34-39.00N 120-40.00W, 34-39.00N 120-35.00W,
      34-27.00N 120-25.00W, 33-55.00N 120-18.00W.
   B. 242020Z TO 242345Z SEP, ALTERNATE
      2020Z TO 2345Z DAILY 25 THRU 27 SEP
      IN AREA BOUND BY
      25-18.00N 117-07.00W, 25-12.00N 117-27.00W,
      26-35.00N 117-53.00W, 26-41.00N 117-33.00W.
   C. 242020Z TO 242345Z SEP, ALTERNATE
      2020Z TO 2345Z DAILY 25 THRU 27 SEP
      IN AREA BOUND BY
      00-17.00S 121-28.00W, 00-07.00S 110-21.00W,
      03-24.00S 109-33.00W, 03-24.00S 110-21.00W.
   D. 242242Z TO 250133Z SEP, ALTERNATE
      2242Z TO 0133Z DAILY 25 THRU 27 SEP
      IN AREA BOUND BY
      17-57.00N 140-23.00W, 06-13.00N 137-52.00W,
      06-30.00N 136-25.00W, 18-15.00N 138-53.00W.
2. CANCEL THIS MSG 280233Z SEP 22.// 

A second Navigational Warning for this launch, NAVAREA XII 695/22, is identical.

The locations of the first three hazard areas A to C from the Navigational Warning are indeed very similar to those for NROL-71 in 2019: compare for example to this map for NROL-71 from this december 2018 post:

 

NROL-71 from January 2019. click to enlarge

Area D, the upper stage deorbit area, is situated slightly more south and is a bit more elongated than it was for NROL-71, for unclear reasons. The upper stage deorbit happens at the end of the first revolution. The deorbit burn might be visible from central Asia around 23:10-23:20 UTC.

In 2019, NROL-71 was launched into a 395 x 420 km, 73.6 degree inclined non-sun-synchronous orbit and I expect the orbit of the NROL-91 payload to be very similar.

Here is my pre-launch orbital estimate for the NROL-91 payload based on this assumption:

 

NROL-91                      for launch on 24 Sep 2022 at 21:53:00 UT
1 70001U 22999A   22267.91180556  .00000000  00000-0  00000-0 0    06
2 70001 073.6000 044.7175 0018421 155.1634 324.7303 15.53162541    00

 

If NROL-91 indeed launches at 21:53 UT on the 24th, the orbital planes of the payload and USA 290 will end up at a 90-degree angle to each other, as can be seen in the polar view below:

polar view of the orbital plane relative to that of USA 290. Click to enlarge

 

If the launch is scrubbed on the 24th, and if indeed this specific orbital plane at 90-degree angle to that of USA 290 is aimed for, the launch time will shift ~13 minutes earlier each day.

USA 290 at the time was widely believed to be a new generation electro-optical reconnaissance (IMINT) satellite, a follow-on on the KH-11 ENHANCED CRYSTAL program. That it was launched, as NROL-91 will be, in a non-sun-synchronous orbit is odd though, for an optical reconnaissance satellite. 

One really wonders why the sun-synchronous polar orbit typical for such missions (and typical for earlier generation KH-11 EVOLVED ADVANCED CRYSTAL missions) was dropped in favour of this new 73.6 degree orbital plane. What is the advantage of this new orbital configuration? Or are USA 290 and NROL-91 perhaps not electro-optical systems, but something else?

NROL-82: an upcoming new KH-11 EVOLVED ENHANCED CRYSTAL launch [UPDATED]

image: ULA

(updated 27 Apr 2021 with first observational orbit, see end of post)

If the weather and the launch Gods cooperate, ULA will launch a Delta IV Heavy with a classified payload for the NRO on 26 April 2021. The launch is designated NROL-82 and the payload will likely receive the designation USA 314. In a tweet from April 19, ULA mentions a prospective launch time of 20:46 UT.

Several lines of evidence lead us to believe that the payload is a KH-11 EVOLVED ENHANCED CRYSTAL optical reconnaissance satellite, colloquially also known as a 'Keyhole'. It is the kind of satellite that makes these kind of detailed pictures of areas of interest for the NRO.

A map in the ULA Mission Overview for this launch, and the Navigational Warnings issued for this launch (NAVAREA XII 173/21 and HYDROPAC 1221/21) provide information on the launch azimuth and from that the orbital inclination targetted. Likewise the position and time window of the upper stage deorbit area provides - in a very broad sense- information on the orbital altitude aimed for. Together they indicate a launch into a sun-synchronous Low Earth Orbit with an orbital inclination near 98 degrees. This is a very familiar orbit, as we will discuss later in this post.

Below is a map I prepared depicting the hazard areas from these Navigational Warnings as well as the launch trajectory I calculate based on this information:

click map to enlarge

The listed times along the track are for launch at 20:46 UT into the 250 x 1020 km, 97.9 degrees inclined estimated orbit below:

 NROL-82 (USA 314)          for launch on 26 April 2021 at 20:46:00 UT
1 70002U 21999A   21116.86527778  .00000000  00000-0  00000-0 0    03
2 70002 097.8600 222.0898 0548970 157.1680 337.2110 14.78203944    02

 

The text of the Navigational Warnings:

220434Z APR 21
NAVAREA XII 173/21 (also: HYDROPAC 1221/21)
EASTERN NORTH PACIFIC.
EASTERN SOUTH PACIFIC.
CALIFORNIA.
1. HAZARDOUS OPERATIONS:
   A. 2016Z TO 2257Z DAILY 26 THRU 28 APR
      IN AREA BOUND BY
      34-38N 120-40W, 34-36N 120-30W,
      34-07N 120-39W, 34-08N 120-44W.
   B. 2016Z TO 2257Z DAILY 26 THRU 28 APR
      IN AREA BOUND BY
      22-57N 120-46W, 23-47N 125-18W,
      26-27N 124-45W, 25-36N 120-08W.
   C. 2016Z TO 2257Z DAILY 26 THRU 28 APR
      IN AREA BOUND BY
      13-28S 121-20W, 10-47S 138-34W,
      00-47S 136-41W, 03-52S 119-54W.
   D. 2253Z TO 0029Z COMMENCING DAILY
      26 THRU 29 APR IN AREA BOUND BY
      63-14S 174-16W, 32-49S 159-58W,
      33-23S 156-28W, 64-16S 168-07W.
2. CANCEL THIS MSG 300129Z APR 21.

 

Area D from the Navigational Warnings, located in the southern Pacific Ocean, appears to be the deorbit area for the Delta Cryogenic Second Stage (DCSS). The DCSS deorbit takes place some two hours after launch, just after the start of the second revolution (with the deorbit burn happening over the Arctic, near the end of the first revolution).

As mentioned above, the orbit that seems to be targetted is one that is very familiar in terms of orbital inclination and sun-synchronous character. It is the typical orbit of a KH-11 EVOLVED ENHANCED CRYSTAL electro-optical reconnaissance satellite. Several years ago I discussed the KH-11 orbital constellation in depth on this blog ("Past and future of the KH-11 Keyhole/Evolved Enhanced CRYSTAL constellation" - 2013). As a side note, the type of rocket used to launch NROL-82 is consistent with a KH-11 launch too: the Delta IV Heavy has a long history of launching KH-11's.

Currently there are at least three, and possibly four active KH-11 satellites on orbit: USA 186 (2005-042A), USA 224 (2011-002A), USA 245 (2013-043A), and possibly USA 290 (2019-004A).  The latter, USA 290, is in an odd orbit for a KH-11 and its identification as a KH-11 is open to questioning (I will discuss this later in this blog post).

Historically (see "Past and future of the KH-11 Keyhole/Evolved Enhanced CRYSTAL constellation"), new KH-11 satellites are launched into one of two primary orbital planes some 48 degrees apart in RAAN: a "primary East" plane and a "primary West" plane. The time window and the 20:46 UT launch time given by ULA for the upcoming April 26 launch corresponds well with targetting the "primary East" plane. This orbital plane results in passes around local noon and midnight. The KH-11 satellite currently occupying this orbital plane is USA 224 launched 10 years ago in 2011.

 

USA 224 imaged in June 2014. click image to enlarge

KH-11 constellation (minus USA 290), situation mid-April 2021 (polar view). Click to enlarge

 

The orbital plane of USA 224 passes over the launch site of NROL-82, Space Launch Complex 6 (SLC-6) at Vandenberg Air Force Base, around 21:20 UT on April 26. This is a difference of some 35 minutes with the launch time (20:46 UT) from the ULA tweet.

In 2011, when USA 224 itself was launched to replace USA 161 in the primary East plane, the launch occurred some 20 minutes before the USA 161 orbital plane crossed over the launch site (a similar time difference would hence see launch around 21:00 UT for the upcoming April 26 launch).

If history is our guide, the following sequence of event will likely happen. To start with, NROL-82 will be launched into the KH-11 Primary East plane, with an orbital inclination of ~97.9 degrees and orbital altitude of ~250 x 1020 km, almost co-planar with USA 224. The illustration below shows the orbital plane situation around orbit insertion. Note the similarity of the orbital planes of NROL-82 and USA 224:

 

expected situation just after launch of NROL-82. click to enlarge

 

After a check-out period of a few weeks, the NROL-82 payload (likely designated USA 314) will take over the primary plane mission from USA 224, the satellite previously occupying this orbital plane. 

Next, after USA 314 has taken over its role, USA 224 will be moved away from the primary plane, into a new orbital plane with RAAN some 10-20 degrees East of the primary plane: the so called '"secondary East plane". It will also lower its apogee and take up a ~400 km altitude orbit. In this new orbit it will continue to be operational for several years, entering its extended mission phase. 

From this moment on, for the first time since the deorbit of USA 161 in the winter of 2014-2015, all the two primary planes and all the two secondary planes will be occupied by a KH-11 again. The orbital constellation will become something like that in the image below:

Approximate KH-11 constellation after expected rearrangement later this year. Click to enlarge

 

How about USA 290?

You will have noted that after a brief initial mention, I carefully left USA 290, launched in 2019, out of the discussion so far. So what about that object? Is it a KH-11?

USA 290 (2019-004A) was launched as NROL-71 from Vandenberg on a Delta IV Heavy on 19 January 2019 (see an earlier blogpost) and it was suspected by some noted analysts to be a KH-11. It however went into a weird, 73.6 degree inclined ~400 km altitude orbit that is not sun-synchronous and nothing like previous KH-11 orbits. So, had the NRO broken with the previous 'classic' pattern of the KH-11 orbital constellation and were they trying something new?

The identification of  USA 290 as a KH-11 never has been sitting well with me. The odd orbital inclination and non sun-synchronous character of the orbit gives few reasons to think it is an IMINT mission.

In light of the apparent return to the known 'classic' KH-11 constellation with the upcoming launch of NROL-82, I have again started to foster these doubts. Maybe USA 290 isn't a KH-11 after all but something else, something experimental (readers of this blog will have noted that the past 4-5 years, a lot of NRO launches appear to be experimental, going into 'new' previously unseen types of orbit. Some of these are, I suspect, radar imaging satellites).

Ted Molczan has recently suggested that USA 290 is a KH-11, and that its odd orbit is inspired by that of the notorious 'Misty' stealth IMINT satellites of the 1990-ies which were launched in ~65 degree orbits. Basically, he argues that USA 290 is a 'Misty' imaging satellite without the stealth!

I remain agnostic at best about the identity of USA 290. Perhaps, if new payloads are launched into similar orbits over the coming years, the picture will become more clear. For now, I regard USA 290 as an oddity, and not necessarily a KH-11.

UPDATE 27 Apr 2021 11:00 UT

Cees Bassa optically observed the NROL-82 payload on the 2nd and 3rd revolution. Radio observers including Scott Tilley are also tracking it.

Based on a hybrid optical/radio orbit computed by Scott Tilley, the orbital altitude is somewhat different than expected, the orbit less eccentric: but the orbital plane is even closer to that of USA 224.

The orbital plane is very close to that of USA 224 indeed: a ~1 degree difference in RAAN and 0.1 degree difference in orbital inclination.

Orbital altitude currently appears to be about 525 x 760 km, i.e. less eccentric than our initila pre-launch estimate. That of USA 224 is 256 x 997 km.

The NROL-82 payload might manoeuvre in the coming days and weeks in order to have it's apogee and perigee altitudes match with  that of USA 224.

click to enlarge

USA 290 (NROL-71)

click image to enlarge

The photograph above is not the best of images, but it does show the trail (faint) of  USA 290, the payload of the January 19 NROL-71 launch from Vandenberg. I shot it last Monday morning, February 11th.

I wrote about this odd launch earlier (here). Before the launch, it was widely suspected that this was a new electro-optical reconnaissance satellite, a block V KH-11 ADVANCED CRYSTAL ("Keyhole"). So we expected it to go in a 98-degree inclined, ~1000 x 265 km sun-synchronous orbit, the orbit typical for new primary plane additions to the KH-11 constellation.

But then the Maritime Broadcast Warnings for the launch came out, and it became clear that the splashdown and deorbit zones did not fit a launch azimuth consistent with such an orbit (see a previous post where this was discussed). Instead, it suggested a 74-degree inclined, 265 x 455 km non-sunsynchronous orbit. Which was very odd, as it was completely against expectations for a new KH-11.

click map to enlarge

The launch was postponed several times, but finally happened on 19 January, a month later than it was originally slated. The launch postponements added a new mystery: the shifting launch window times with each postponement suggested a particular orbital plane with a nodal precession of -2.27 deg/day was aimed for.

The question was: why, if  NROL-71 was going into a 74-degree inclined orbit? Targetting a specific orbital plane only makes sense when the payload is part of a constellation of satellites. But NROL-71 was not targetting the orbital inclination of the existing KH-11 constellation (currently consisting of USA 186, USA 224, USA 245). And it's orbit is (as we will see) not sun-synchronous. It is very odd (and does suggest there will be future objects going into a similar orbit).

After launch on 19:10 UT on January 19th, 2019, there initially was no optical visibility as nighttime passes in the Northern hemisphere were in earth shadow.

But radio observers (a.o. Sven Grahn, Scott Tilley, Cees Bassa, Nico Jansen) quickly picked up the radiosignals of the payload at 2242.5 MHz. These showed that the payload was in a 73.6 degree inclined non-sunsynchronous ~400 km Low Earth Orbit, much as we had gleaned pre-launch from the hazard zones in the Maritime Broadcast Warnings.

As USA 290 slowly emerged from Earth shadow passes, the first optical observations were made by Russell Eberst in Scotland in the morning of 1 February. Next Leo Barhorst in the Netherlands soon followed.

These initial passes were very low in the sky, too low for my urban environment where I need elevations above 20-25 degrees to clear the rooftops. And when as February progressed the passes gradually climbed higher in the sky for my location, weather was not cooperating.

But in the morning of 11 February I finally had a clear sky, and managed to image USA 290, photographically as well as on video. As the illumination angle was not the best, the payload stayed a bit faint, but still was bright enough to register as a faint trail on the photograph (the bright star near the trail is gamma Cygni. Image taken with a Canon EOS 60D + EF 2.0/35 mm lens):

click image to enlarge

The object showed up well on the video (WATEC 902H + Canon FD 1.8/50 mm lens), yielding good astrometry:




The optical observations helped to better define the orbit. They show USA 290 is in a 393 x 422 km, 73.6 degree inclined, non-sunsynchronous orbit.

Apart from abandoning the 97.9 degree inclined sun-synchronous orbit of the primary plane KH-11's, it also abandoned the 1000 x 260 km orbital altitude that was previously typical for new primary plane launches. The orbital altitude is closer to the extended mission, secondary plane KH-11's, the sole representative of which (USA186) currently is in a 262 x 452 km orbit.

Of course, in terms of orbital inclination and nodal precession (the non-sunsynchronous character) it doesn't compare to any of the previous KH-11.

(Note: a few year ago I wrote a series of detailed posts analysing the orbital constellation of the KH-11, and the typical changes in orbital plane and orbital altitude when a new addition to the constellation was launched: see the posts here and here).

click to enlarge

click to enlarge

click to enlarge

So, there is something new under the sun, in more than one way. While the general consensus still is that USA 290 is an electro-optical bird in the ADVANCED CRYSTAL lineage, the radical break with previous orbital structures for this series of satellites is highly interesting. It will be interesting to follow this new object, and see how things develop with future launches.

Over the last two years, the black space program in Low Earth Orbit has become much more exciting, with some new eyebrow-raising additions unlike any previous missions. Examples are USA 276, the failed Zuma launch, and now USA 290, all launches from the past 1.5 years.

I like it: just when we thought things were getting perhaps a tad predictable, we are suddenly treated to a number of surprises, resulting in new stuff to ponder and analyse.