Optically observing the RNLAF's 6U cubesats BRIK-II, HUYGENS and BIRKELAND

 

WATEC 902H2 Supreme camera with Samyang 2.0/135 mm lens and GPS time inserter

The Royal Netherlands Air Force (RNLAF) launched its first satellite, the cubesat BRIK-II (2021-058F), two years ago as part of the Virgin Orbit Tubular Bells rideshare on 30 June 2021 (see an earlier post here).

Two more satellites, HUYGENS (2023-001CN) and BIRKELAND (2023-001G) were recently launched for the RNLAF as part of the SpaceX Transporter 6 rideshare on 3 January 2023. These two satellites, which move in the same orbital plane, are co-owned by the RNLAF and the Norwegian Ministry of Defense.

The satellites are 6U cubesats, with the bus measuring 10 x 20 x 30 cm (roughly the size of a shoebox). Huygens and Birkeland have unfolding solar panels expanding their size to about 30 x 60 cm.

 

Brik-II during assembly and testing (image: Netherlands Ministry of Defense)

 

Rendering of Huygens (image: Nanoavionics)

 

orbits of the Brik-II, Huyugens and Birkeland cubesats

 

Over the past two weeks I have imaged all three satellites from Leiden - in the case of  Huygens and Birkeland even on multiple nights - using my WATEC 902H2 Supreme camera fitted with a 2.0/135 mm light telelens. 

Brik-II remained very faint during the one pass I imaged, but Huygens and Birkeland were surprisingly easy to see, as can be seen in the framestacks and video's further down in this blogpost.

 

BRIK-II

Below are a framestack and a short video of the March 30 Brik-II detection. I have processed the video for visibility (which also increased the noise) as the cubesat was very faint: look for a very faint, fast object coming from the upper left corner.

I had tried to image the satellite earlier on several occasions the past two years, but this was the first time I had a positive detection.

 

Brik-II, framestack from footage taken March 30, 2023

video footage of Brik-II (very faint!)

 

HUYGENS and BIRKELAND

Below are framestacks and video footage of passes of Huygens and Birkeland taken on March 30, April 4 and April 8, 2023. These two cubesats were much more readily visible than BRIK-II and you'll have no problem seeing them in the footage

The video footage of Huygens is from April 4, of Birkeland from April 8. They were (on all three nights involved) clearly better visible than Brik-II was on March 30. This is partly due to a better observing geometry, but it does seem that Huygens and Birkeland are really intrinsically brighter than Brik-II. They reached magnitude +7.5 to +8.

First, imagery - framestacks and brief video footage - of Huygens (2023-001CN) obtained on 30 March and 4 April, 2023:

Huygens on March 30,2023 (framestack)

Huygens on April 4, 2023 (framestack)

 video footage of Huygens on April 4, 2023

 

Next, imagery - a framestack, and a longer video - of Birkeland (2023-001G) obtained on 8 April 2023. The bright object initially seen passing in the upper left corner is a Starlink satellite (Starlink-5226): Birkeland is the fainter object coming from bottom right:

Birkeland on April 8, 2023 (frame stack)

 

 video footage (longer video) of Birkeland on 8 April 2023

 

Equipment

All the imagery was captured with a WATEC 902H2 Supreme low-light-level cctv camera fitted with a Samyang 2.0/135 mm lens, filming at 25 frames per second. Accurate timing of the video frames was provided with a BlackBoxCamera GPSBOXSPRITE-2 GPS time-inserter.

The system delivers an astrometric accuracy of about 15 arcseconds. The FOV is about 2.7 x 2.0 degrees. The footage was shot from my home in the center of Leiden, the Netherlands (52.154 N, 4.491 E).

The image below shows the equipment in question. The box at left is the GPS time inserter. The PAL video feed from the WATEC camera goes from the camera into the time inserter, which imprints each individual videoframe with a millisecond-accuracy time derived from GPS signals. After passing through the time inserter the video feed is going to a digitization dongle, and is next recorded on a laptop.

WATEC 902H2 Supreme camera with Samyang 2.0/135 mm lens and GPS time inserter

 

I used my observations to provide these orbit updates for Huygens and Birkeland:

HUYGENS
1 55093U 23001C   23098.81960162 0.00006982  00000-0  37378-3 0    02
2 55093  97.4857 159.4790 0014652 237.3630 122.6188 15.14989127    06

rms 0.004 deg   arc 30.85 Mar - 8.83 Apr UTC


BIRKELAND
1 55015U 23001G   23098.83187223 0.00009789  00000-0  53865-3 0    04
2 55015  97.4960 159.3843 0009401 256.5788 103.4395 15.14067850    03

rms 0.003 deg   arc 4.88 - 8.84 Apr UTC

 

These observations have wet my appetite to try to image more cubesats. The observations also underline (as we recently did in a conference publication as well) the power of relatively small but sensitive equipment. You really don't need a big telescope to track cubesats.

More on these satellites

With Brik-II, Huygens and Birkeland, the RNLAF is now entering active operations in the Space Domain.

Huygens and Birkeland are named after two iconic scientists, the Dutch Christiaan Huygens (1629-1695) and the Norwegian Kristian Birkeland (1867-1917). They were developed as part of the joint Milspace-2 program of the Dutch and Norwegian Ministries of Defense.

The two satellites operate as a pair, in the same 97.5 degree inclined orbital plane, Huygens currently in a 531 x 511 km orbit, Birkeland currently in a 530 x 517 km orbit. 

Their primary mission is ELINT: the geolocation and fingerprinting of Radar emissions. The two satellites are also used for experiments with formation flying.

Huygens and Birkeland orbit

Brik-II is named after Brik, the very first aircraft of a forerunner of the RNLAF, the "Luchtvaartafdeling" of the Royal Dutch Army, back in 1913. 

In Dutch, the word "brik" has several meanings: it is Dutch for "brick", as well as a slang name for a means of transportation (a cart or a car), in the latter case usually with the added connotation of it being somewhat decrepit.

The satellite is in a 60.7 degree inclined, 515 x 466 km orbit. Its experimental mission includes ELINT, communications, and Spaceweather monitoring. It was built for the Dutch Ministry of Defense by ISISpace in Delft. It is operated by the Defense Space Security Center in Breda.

 

"Brik", the first aircraft of the Dutch military, in 1913 (image Dutch Ministry of Defense)

Brik-II orbit

 

 

A surprisingly bright flare from a 6U Cubesat

​The 240 frames frame stack above, which is from the video below, shows the classified Japanese satellite IGS Optical 5 (2015-015A). But at 21:14:05.5 UT, somethings else moving nearly parallel to the satellite briefly flares up.

The flaring object in question, producing a flare of at least magnitude 0, is TYVAK 182A (also known as ELO Alpha), 2021-034D. This is a 6U cubesat. I am quite surprised to see such a bright flare from such a small object!

The video was taken from Leiden, the Netherlands, with a WATEC 902H2 Supreme fitted with a Samyang 1.4/35 mm lens.

First positive observations of the LED beacon of the NAPA-2 6U cubesat

 

On June 30, 2021, a Falcon 9 launched several cubesats in a rideshare launch called Transporter-2. One of the payloads was a 6U cubesat called NAPA-2. 

This cubesat was built by the Dutch company ISISpace in Delft (the same company that built Brik-II) for the Royal Thai Air Force. It is an IMINT satellite, carrying two small Earth observation camera's. It is in a 97.5 degree inclined sun-synchronous 520 x 540 km orbit with passes around local midnight and noon.

This is the NAPA-2 cubesat after assembly (image courtesy of ISISpace): the 6U cubesat measures about 10 x 20 x 30 cm.

image (c) ISISpace, used with permission.

NAPA-2 has an interesting novelty: it carries a beacon of 12 bright LED's that can be switched on and off by the satellite operators. 

It is an experiment to see if such a bright artificial lightsource on the satellite can aid in optically tracking it.

The past few days saw the commissioning of this feature. ISISpace had asked me whether I could try to image the LED beacon from Leiden. Attempts to image it were made on three nights. 

The first attempt, on August 24 using a 1.4/85 mm lens, was negative.

The second attempt was on August 25. The operators had reorientated the satellite such that the LED's were pointing at the groundstation. This attempt was marginally positive: it was seen but the satellite was extremely faint and barely visible and the trail was lost in the noise background in a frame stack.

A third attempt was made last night, in the early hours of 27 August. This time I used a more powerfull lens, the Samyang 2.0/135 mm. The camera was a WATEC 902H2 Supreme operating at 25 frames/s.

The result was a positive detection: the LED beacon of the satellite, although faint, was unambiguously imaged. The range to the satellite was 598 km during the observation. It was imaged around culmination at 61 degrees altitude in the east.

 

click to enlarge

 

Below is the video: the object, coming into the FOV from the right, is very faint, but visible. It disappears near the center of the image because the LED was switched off: the operators operated it is a "3-seconds-on, 1-second-off" mode last night.

Below is a framestack of 60 frames from the video (2.4 seconds of footage). A faint but unmistakable trail can be seen entering the FOV from the right: the LED beacon of NAPA-2! The bright star near the bottom of the image is 13 Persei.

Below is a negative image version of the same stack: and a positive version where I pushed the image such that the trail comes out better.

 

 

It should be noted that the cubesat was imaged in a part of it's trejactory where it was in Earth shadow: so all the light solely comes from the 12 LED's!

This is the LED array on the satellite (image courtesy of ISISPace):

image (c) ISISpace, used with permission.

Amazing that 12 LED's are visible from a distance of almost 600 km! 

The LED beacon does not operate continuously: it is only briefly switched on when passing over a tracking station (in this case, my observing location). It reaches an Rmag of about +10.

Below are the astrometric residuals relative to CSpOC elset 21239.30175625 (angles are in degrees, delta T in seconds), showing the good match:

     STA   YYday HH:MM:SS.sss   AZ     EL     XTRK     deltaT   Perr
( 1) 4353  21239 00:52:38.401   78.0   60.9   -0.02     0.02    0.023
( 2) 4353  21239 00:52:38.441   77.9   60.9   -0.02     0.04    0.033
( 3) 4353  21239 00:52:38.600   77.7   60.9   -0.02     0.03    0.030
( 4) 4353  21239 00:52:38.920   77.2   61.0   -0.02     0.03    0.025
( 5) 4353  21239 00:52:38.960   77.2   61.0   -0.02     0.06    0.044
( 6) 4353  21239 00:52:39.241   76.7   61.0   -0.02     0.03    0.031
( 7) 4353  21239 00:52:39.561   76.2   61.0   -0.02     0.03    0.031
( 8) 4353  21239 00:52:39.600   76.2   61.0   -0.02     0.05    0.044
( 9) 4353  21239 00:52:39.761   75.9   61.0   -0.02     0.03    0.025
(10) 4353  21239 00:52:39.801   75.9   61.0   -0.03     0.04    0.041

rms     0.03367

Imaging objects from the 'Tubular Bells' launch

image: Virgin Orbit

During the first days of July, I have tried to image objects from the June 30 Virgin Orbit 'Tubular Bells' launch, that launched a number of smallsats including Brik-II, the first Dutch military satellite (see earlier posts here and here).

I so far managed to unambiguously image three objects from the launch. One of these is probably the LauncherOne upper stage, the other two must be payloads.

On July 2nd, I imaged objects A and B, A using a 2.0/135 mm and B using a 1.4/85 mm lens on the WATEC 902H2 Supreme low light level video camera. B was very faint and barely visible.

On July 4th, I unambiguously imaged objects B and H using a 2.0/135 mm lens.

Object A is relatively bright and well ahead of the other objects. It is in a somewhat lower orbit: a 418 x 504 km orbit, whereas the other objects are in a 496 x 522 km orbit. So object 2021-058A almost certainly is the LauncherOne upper stage.

Below is video of the A-object, shot on July 2nd with the 2.0/135 mm lens. The bright star top left is Polaris. I could not see the other objects (passing about 30 minutes later): for passes to the north of me, the illumination angle is less favourable than for passes to the south of me.

 

The B and H objects are fainter, and only visible during passes to the south of me. The video below shows them, faint but unmistakenly, during a pass in evening twilight on July 4th (sun at only 7 degrees below the horizon, so the sky background was still quite bright).

 

A fourth object, Object C, was possibly seen on July 2nd when I watched the pass live on screen, but I could not see it anymore when inspecting the footage afterwards. 

Objects D, E, F and G were not seen, but on all imaged passes observing conditions were not perfect (on July 2, cirrus clouds were invading the FOV around the time of the objects D, E, F and G passing; while on July 4th the sky background was still very bright).

It is not clear which object is which at the moment, although I have reasons to believe that Brik-II must be either object D, E or F. I have some suspicion that objects B and H are part of STP27-VPA. [edit: see updates below: Object H was, but B is not).

UPDATE:

I obtained even better imagery of the two STORK objects (B and C) on July 17:

 

UPDATE 14 Jul 2021:

Object B actually appears to be one of the STORK satellites, based on Dopplerfitting of  radiosignals received at 401.1 MHz (and first detected by Alicja Musial in Poland). Object C also appears to be a STORK, based on Doppler fitting of the radio signal.. 

Objects D and E are now listed by CSpOC as CNCE3 and CNCE1, which are part of STP27-VPA.

Objects F, G and H then are Brik-II, Gunsmoke-J and Halo-NET (the latter two are part of STP27-VPA), with not certain which is which.

UPDATE 16 Jul 2021

Object F is now identified as Brik-II. Object H (One of the two objects I imaged on July 4) is now identified as Gunsmoke-J 2. 

As, from radio Doppler fitting, we know objects B and C are the STORKS (not yet identified as such by CSpOC), this means object G must be Halo-NET:

Object A    LauncherOne rb

Object B    Stork

Object C    Stork

Object D    CNCE3*

Object E    CNCE1*

Object F    Brik-II

Object G   Halo-NET*

Object H    Gunsmone-J 2*

* part of STP27-VPA

Bob Christy has pointed out that there might be a swap of the A and G designation in the future, to make the A designation a payload rather than the RB.

Navigational Warnings have appeared for the launch of the first Dutch military satellite, Brik-II [UPDATED]

 

artist impression of Brik-II in space (The Netherlands Ministry of Defense)

It was originally scheduled for launch in 2019, and postponed several times. But it now seems it will finally happen, on or near June 30: the launch of the Netherlands' first own military satellite, a 6U cubesat named 'Brik-II'.

The ministry of Defense of the Netherlands is partner in several already launched military satellites, but this will be the first satellite that is truely it's own. 

Brik-II was built by the Dutch aerospace company ISISPACE in cooperation with Delft Technical University, Oslo University and NLR and will be operated by the Royal Netherlands Air Force (RNLAF).

It is a small 6U cubesat (10 x 20 x 30 cm, weighing 10 kg) that contains equipment for communications relay, for Space Weather monitoring, and for ELINT (see my earlier post on Brik-II here).

 

image: The Netherlands Ministry. of Defense

 

Brik-II will be launched by Virgin Orbit as part of their  'Tubular Bells, part 1' mission that launches a number of small payloads: apart from Brik-II for the RNLAF, it will launch three or four (sources differ on the number [edit July 1: it were four payloads]) payloads for the US Dept. of Defense, and two payloads for the SatRevolution company.

The launch is an airborne launch, using a two-stage LauncherOne rocket launched from the Virgin Orbit Boeing 737 747-400 'Cosmic Girl' in front of the California coast.

images: Virgin Orbit

The launch was postponed several times, including this month, but Navigational Warnings have now appeared indicating an aimed launch date of 30 June (with backup dates July 1-5). 

The 3-hour launch window runs from 13:00-16:00 UT [edit: launch eventually was at 14:47 UT]. According to Virgin Orbit, the orbit aimed for is a 60-degree inclined circular orbit at ~500 km altitude. [edit] An infographic by the Royal Dutch Air Force mentions an orbital inclination of 60.7 degrees.

This is the navigational warning, NAVAREA XII 292/21:

 262041Z JUN 21
 NAVAREA XII 292/21(18,21).
 EASTERN NORTH PACIFIC.
 CALIFORNIA.
 1. HAZARDOUS OPERATIONS, ROCKET LAUNCHING
    301300Z TO 301600 JUN, ALTERNATE
    1300Z TO 1600Z DAILY 01 THRU 05 JUL
    IN AREAS BOUND BY:
    A. 33-36-44N 120-23-05W, 33-24-22N 120-17-14W,
       32-55-44N 119-55-39W, 30-38-19N 118-13-14W,
       28-24-39N 116-37-52W, 28-03-32N 116-17-09W,
       28-10-00N 116-05-44W, 28-24-41N 116-11-12W,
       29-07-31N 116-36-05W, 30-50-51N 117-46-19W,
       33-08-50N 119-32-16W, 33-33-26N 119-54-35W,
       33-45-27N 120-06-00W, 33-43-27N 120-16-02W,
       33-36-44N 120-23-05W.
    B. 23-13-25N 112-20-09W, 23-51-12N 113-00-01W,
       24-04-05N 113-17-34W, 24-00-35N 113-35-42W,
       23-49-04N 113-49-26W, 23-23-22N 113-46-59W,
       22-46-17N 113-39-25W, 22-01-49N 113-03-13W,
       21-54-11N 112-57-20W, 21-46-52N 112-49-48W,
       21-41-03N 112-38-21W, 21-40-45N 112-26-55W,
       21-44-25N 112-12-12W, 21-52-03N 112-03-22W,
       22-03-39N 111-58-08W, 22-13-42N 111-57-29W,
       22-26-28N 112-02-59W.
 2. CANCEL THIS MSG 051700Z JUL 21.

I have plotted the two areas on the map below, along with the trajectory for a 60-degree inclined ~500 km orbit, with times along the trajectory valid for launch at 13:00 UT, the start of the window (it will, however, probably launch a little after that: the second map is for a 60.7 degree inclined orbit and denotes times in minutes after launch):

click map to enlarge

click map to enlarge

While Virgin Orbit mentions a 500 km target orbit for 'Tubular Bells', earlier news reports on Brik-II mentioned a 600-700 km orbital altitude.

Brik-II is named for an earlier 'Brik', the name of the very first aircraft of the RNLAF progenitor, the 'Luchtvaartafdeeling', 108 years ago, in 1913:

The first Brik, photographed in 1916. Photo: Netherlands Institute for Military History

 

"Brik" has several meanings in Dutch. Originally it was a name for a type of ship (equivalent to the English 'Brig'), and it was also used for carts. Later, it became a name for old bicycles and old, decrepit  cars. "Brik" in addition is one of several Dutch names for a brick, hence the mission patch for Brik-II:

Brik-II mission patch (collection author)

Update 1 July 2021:

CSpOC TLE's have appeared on Space-Track for 8 objects from the launch: the seven payloads and the LauncherOne upper stage. They have catalogue numbers 48871 to 48878. The first object, 48871, is in a lower orbit  of 418 x 504 km and almost certainly the LauncherOne upper stage. The seven others are close together in higher, approximately 495 x 522 km orbits, inclined between 60.66 to 60.70 degrees.

Of these objects, either object D, E, or F (catalogue nrs. 48874, 48875, 48876) appears to be Brik-II.

My pre-launch estimate for the orbit appears to have a quite reasonable agreement with the eventual orbits for these objects (the green arrow and object in the images below indicates my pre-launch estimate. the plot is for 1 July 6:35 UT,  about 16 hours after launch):

click images to enlarge