The tumbling period of the USA 144/Misty-2 Decoy (99-028C)

On August 25 and August 27, I obtained a series of photographs of the USA 144/Misty-2 decoy (see here and especially here). On the request of Pierre Neirinck, I did some simple photometry on the image series, to see whether I could retrieve information out of this on the current tumbling period of the object.

It concerns the following two image series. In both cases, the object is moving from right to left, and the image series has to be "read" from right to left (i.e., the most right image is the earliest in time, the most left the latest). Some clear brightness variation from image to image is already apparent.

Click images to enlarge

From these images, the following two partial photometric curves were obtained, both suggesting a period near ~70 seconds:

Click images to enlarge

Next I combined these two partial curves (from two separate nights) into one amalgamated curve (this included of course some data normalization/scaling), shown below:

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The result is a curve that can be approximated by a sinusoid with a period of 71 seconds. This suggests the object's current tumbling period is 2 * 71 = 142 seconds.

(in the curve above, the dark dots are (normalized) data points, the grey line is a 20-point running average, and the black line a sinusoid with a period of 71 seconds)

The Terra (EOS AM-1) satellite, IGS 1B near M31, and more

Yesterday evening the street lights went out in town, due to some malfunction. This made my sky a bit darker than usual.

I captured the KH-12 Keyhole USA 186 (05-042A) in late twilight, followed by a fine pass of IGS 1B (03-009B) some 45 minutes later. It was very bright and on one of the images I captured it passing M31, the Andromeda galaxy.

Click image to enlarge

Later that night (with the streetlights on again) I imaged the USA 144 decoy (99-028C) passing through northwest Pegasus. In one of the images, the Terra (EOS AM-1) satellite (99-068A) was captured as a bright stray as well. This satellite carries the ASTER and MODIS remote sensing sensors well-known to Earth scientists. They were used a.o. to create the Blue Marble images of the Earth.

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A keyhole, a Trumpet, IGS 1B, and strays

Yesterday evening it was clear again. I captured the KH-12 Keyhole USA 186 (05-042A), and also IGS 1B (03-009B). In addition, two strays were captured, and the EF 100/2.8 Macro USM was used to capture the Trumpet ELINT USA 184 (06-027A) again.

In one of the pictures with USA 186, a piece of Delta 1 debris, 75-027E, was captured as a bright stray. In one of the images with IGS 1B, the Kosmos 1975 rocket (88-093B) was captured as a bright stray. Below is the latter image showing a part of Northern Cygnus:

Click image to enlarge

USA 184 Trumpet (?) ELINT and more

Yesterday in the daytime, it was clouded and rainy. It cleared marvelously in the evning though. I detected the clearings too late to capture the evening Keyhole passes, but captured a number of other objects: IGS 1B (03-009B, a defunct Japanese SAR), Lacrosse 2 (91-017A, a SAR as well), the NOSS 3-3 Duo (05-004 A & B), and two HEO objects: USA 184 (06-027A) and the USA 144 decoy (99-028C) again.

The image below shows the USA 144 decoy again, and is a somewhat better picture than that which I posted in a previous post:

Click image to enlarge

USA 184 was imaged as well, and for the first time by me. It showed up bright. It is probably a Trumpet-class ELINT satellite. It is in a Molniya orbit (see below) and at the time of imaging was at an altitude of 28560 km, over Northern Europe.

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Below is one of the images, plus an animated GIF of all five images, showing the movement perpendicular to the night sky rotation:

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Keyholes, IGS 1B and the USA 144 decoy

Yesterday evening it was clear again. I obtained data on two of the three Keyhole KH-12's, USA 129 (96-072A) and USA 186 (05-042A); on the defunct Japanese SAR IGS 1B (03-009B); and used the EF 100/2.8 Macro USM to capture the enigmatic HEO object USA 144 debris/decoy (99-028C).

The latter object is an interesting one. It was part of the launch of what is believed to be the second stealth reconnaissance satellite, Misty-2. After being picked up by amateur observers and observed for some time, doubts began to grow whether it really was the main payload. Ted Molczan determined from the obital evolution that the object did not appear dense enough to be an operational satellite (i.e. USA 144 itself), something further suggested by the fact that it appeared to be slowly tumbling. Instead, it is either a weird piece of debris from the Delta IV used to launch USA 144; or a deliberate decoy used to get attention away from the real payload. See here, here and here for the details.

Below are one of the images of the USA 144 Decoy which I obtained yesterday evening (it is crossing the northwest corner of Pegasus here), it's orbit, and the launch patch of the 1999 launch.

Click images to enlarge

The object was almost 10 seconds early relative to a 17-day old elset. It shows a slow but clear brightness variation over the image series.

The KH-12 Keyhole USA 186 (05-042A) was 2 seconds early relative to an elset of the previous day. USA 129 (96-072A) was on-time. IGS 1B (03-009B) was 0.25s late.

Observations, a flare, and a logo

Over the past week I could observe on four evening: 11/12, 15/16, 16/17 and 17/18 August. Targets imaged on these nights were the three KH-12 Keyholes (USA 129, 161 and 186), the Japanese prematurely defunct SAR IGS 1B, and the US SAR Lacrosse 3.

USA 186 (05-042A) provided a nice mag. -2 flare on 16 Aug at 20:52:07.0 UTC. It was captured in an image, but unfortunately a too hasty camera pointing meant the satellite run out of the image before the end of the exposure. the flare is on it though, close to the image edge. Below is a crop of the relevant part of the image, and the derived brightness profile.

Note that the "saw-tooth" pattern in the profile is due to the satellite trail being at ~45 deg angle to the pixel orientation, i.e. it is an artifact of the pixel grid.

(click images to enlarge)

In a moment of boredom last weekend, I designed something long overdue for SatTrackCam Leiden (Cospar 4353): a logo.

It is a bit inspired by the "patches" the NRO employees create for their covert space missions (see here and here for a discussion and examples). Hence all symbols used have some meaning (have fun interpreting!). The Latin(ish) roughly translates to "All Your Nightly Secrets Are Belong To Us", a pun at the NRO's credo "We Own the Night" used in some of their patches and the infamous "All Your Base Are Belong To Us" of gaming/internet lore.

Flaring Keyhole USA 161

Yesterday evening/early night was a night with intermittent very clear skies, and large cumulus fields roving the skies. I was lucky though with the selected targets, although some narrowly escaped the roving cloud fields only. I observed 3 Keyholes (USA 129, USA 161 and USA 186) and Lacrosse 3.

USA 129 (96-072A) was imaged low in the sky in a small gap between clouds. USA 186 (05-042A) was imaged in twilight and the trails were rather faint. It briefly flared to mag. -1, before the camera was open, at roughly 22:59:50 UTC.

USA 161 ((01-044A, a Keyhole high-resolution optical reconnaissance satellite, like the other two USA objects mentioned) also briefly flared to -1 a few times. It did so twice while the camera was open, at 23:28:13.40 UTC and 23:30:17.15 UTC, resulting in the pictures below:

(click images to enlarge)

The second image yielded this brightness profile, with the flare saturating at the peak:

(click diagram to enlarge)

USA 186 and IGS 1B

Friday evening saw very clear skies during twilight. Unfortunately, it got clouded soon after. This meant I was prevented from targetting a nice pass of the STSS-ATRR rocket (09-023B) and USA 161 (01-044A). I did image the Keyhole USA 186 (05-042A) however, in deep twilight, obtaining three positions. This object recently (July 15) made a small manoeuvre.

Yesterday was a repeat of the day before: clear at the start of the evening, but clouded out after midnight. Again I missed out on USA 161 and the STSS-ATRR rocket. I did manage to catch the defunct Japanese radar spy IGS 1B (03-009B), obtaining six positions. It was bright while ascending through Ophiuchus in the south, then faded somewhat, became quite bright again while crossing Draco and then faded quickly beyond visibility. Visually, at moments the object was slightly and quickly fluctuating in brightness in irregular fashion. Some of that fluctuation can be seen in the right-hand part of the brightness diagram below, derived from one of the images (top).

(click images to enlarge)

ISS yesterday

Yesterday in twilight, I shot this image of a fine pass of the International Space Station:

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Space Shuttle Endeavour STS-127 in deep twilight (footage)

Yesterday at 22:30 local time (20:30 UTC), in deep twilight with the sun barely 5 degrees below the horizon, I watched a very fine near-zenith pass of the Space Shuttle Endeavour mission STS-127, launched Wednesday. It was bright, being easily visible against the bright blue sky (where only Vega and Arcturus were readily visible). I estimate it must habe been between mag. -1.5 and -2.5.

I filmed part of the pass with my Canon EOS 450D photo camera tethered to my laptop, using 'EOS Camera Movie Record' software (that software basically taps the live view signal of the camera, enabling to "film" with it). Here is some footage, showing it pass near Vega (in the top of the screen). The original movie file is much better quality than this crappy YouTube version by the way (and Blogspot did not want to upload the video alas):

The STSS-ATRR rocket

Wisps of thin clouds filled the sky this evening. These killed any chances of seeing the Shuttle STS-127 and its tank 20 minutes after launch, which would enter eclipse at < 10 degrees above the western horizon.

Later that night, around 00:46 local time, I observed the STSS-ATRR rocket (09-023B), now very near decay. Moving from Cassiopeia through Cepheus, Cygnus and into Ophiuchus, it gradually brightened to mag. +2. It was 1.7s late and about 0.09 degree off-track relative to Ted's 09196.16581104 orbit: so close to decay, the orbit is changing very fast.

The wisps of clouds produced a somewhat eerie picture, shown below, with the rocket moving through Cygnus (bright star near the left trail end is Deneb).

(click image to enlarge)

Keyhole USA 161

Yesterday evening started cloudy, with rain showers. As a result, I missed the splendid NLC display as seen from Belgium and the southern and eastern Netherlands.

After midnight it cleared, and this allowed me to capture the Keyhole satellite USA 161 (01-044A) again. It was nicely on time. A bright mag. 0 stray, which turned out to be the Russian r/b 84-072B, made a similar trajectory 3 minutes earlier.

Below image shows the Keyhole (01-044A) crossing the Milky Way in central Cygnus (I pushed the levels and contrasts of this image a bit in Photoshop to bring out the Milky Way better).

(click image to enlarge)

ISS and Progress chasing each other

This evening I finally was able to see the ISS and the recently decoupled Progress M-02 M (09-024A) cargoship chasing each other over the sky. The couple was some 20 degrees apart, with the Progress leading. A very neat sight.

The Progress was around +2.5 to +3, ISS attained about -3.5 and was distinctly orange. The photo below shows the couple while still low in the sky, ascending in the west.

I also observed USA 161 (01-044A) passing east some 10 minutes later.

(click image to enlarge)

(UPDATED) Where are the observers? A map

Mid-June twilight starts very late, and generally I have not been observing the past 3 weeks due to that, as most interesting objects make passes well after midnight currently (and I need my sleep).

While exploring and practising with some simple GIS/mapping software I might start to use for my work, I made the map below. It shows you where the 20 most active observers regularly contributing position observations to satobs.org are located (the map was created with MicroDEM).

(click image to enlarge)

I also plotted my own two station positions on a combination of SRTM elevation data and a Landsat image. Cospar 4353 is my regular station and is in the centre of Leiden as you can see. My outpost station Cospar 4354 is in the polders to the east of Leiden, just south of the Rhine. (I exaggerated the relief by a factor 5 to better show the coastal dunes)

(click image to enlarge)

Clear nights, and the NOSS 3-4 rocket brightness behaviour

A series of clear nights the past week, allowing a series of observations of the STSS-ATRR rocket (09-023B) and two Keyholes, USA 186 (05-042A) and USA 161 (01-044A). 09-023B keeps being an interesting target, as its orbital evolution is that quick that it necessitates continuous coverage. The current orbit projects decay around mid-August.

About a week ago, on May 19-20th (see here), I obtained images on the NOSS 3-4 r (07-027B). This spent Centaur rocket of the NOSS 3-4 launch shows a slow brightness cycle. I obtained some partial brightness profiles from the trail photographs, including an interesting one covering one of the brightness peaks:

(click diagram to enlarge)

It can be clearly sees that this (10.05 s) part of the cycle consists of two components, a slow modestly exponential brightness development with a short narrow peak superimposed on it.

Flare evening

Yesterday evening 19-20 May was an evening of unpredicted flares.

It started with the International Space Station (ISS) in deep twilight. After a splendid zenith pass, while at 40 degrees altitude descending to the East, it shortly brightened to a dazzling mag. -8.

Somewhat later, still in twilight, it was the Keyhole USA 129 (96-072A) flaring to mag. 0. I caught one of the flares on photograph, just south-east of Regulus against a bright blue twilight background. Below the image ( plus a detail) and the brightness profile:

(click images to enlarge)

Somewhat later in the evening, I was next treated to a spectacular mag. -7 flare of IGS 1B (03-009B) while it was passing through the zenith, alas just after the camera shutter closed. The flare was a bright orange-yellow and lasted maybe a second (approximate time, not too accurate: 21:25:00 UTC).

Apart from these flaring objects, observations were also obtained of the NOSS 3-4 rocket (07-027B), showing its regular slow brightness variation; the keyhole USA 186 (05-042A), the SAR satellite Lacrosse 3 (97-064A) and the STSS-ATRR rocket (09-023B).

I also visually observed the STSS-ATRR itself (09-023A), but due to pressing a wrong button of the stopwatch lost my two points on it alas.

In all, a very fruitful night!

STSS-ATRR rocket again

Yesterday evening it cleared, and I observed the STSS-ATRR (09-023A) through the ETX-70, and photographically also its rocket (09-023B). In addition, I captured the KeyHole satellite USA 186 (05-042A).

The pass of the STSS-ATRR rocket (09-023B) provided the nice image below, showing it while crossing Lyra.

(click image to enlarge)

STSS-ATRR and it's rocket, and Progress-M66 (with photographs)

On May 5, the US military launched a Delta 2 rocket from Vandenberg AFB with the new experimental STSS-ATRR - which stands for Space Tracking and Surveillance System Advanced Technology Risk Reduction satellite. They are also known by the international designation 09-023A, and (for the rocket booster still circling earth) 09-023B.

European observers saw the satellite and the rocket as a thight pair shortly after launch, during their first pass over Europe (see e.g. here and here and here). While the payload was subsequently observed over more passes, the rocket initially got temporarily lost.

Ted Molczan suggested an alternative search orbit (here) and based on that I made an area search with the Meade ETX-70 on the evening of May 8-9, during 20 minutes (between 20:49 and 21:10 UTC) around the nominal pass time from that estimated orbit, covering a 4 degree wide area centered just south of gamma Umi and 11 Umi. During this search I observed an object of around magnitude +6 passing about 2 degrees south of the predicted trajectory, some 4 minutes late.

This indeed turned out to be the rocket. Independant from me, Bram Dorreman also observed it from Belgium that evening on the same pass, bumping into it by chance during his flash observations. With these observations as the basis for an orbital update, it was found and observed by several observers the following nights. Yesterday, in the evening of May 11-12, I photographed it (see below). During a fine zenith pass near 21:50 UTC it appeared as an easy naked-eye object, reaching mag. +2.5 in the zenith.

In below two (out of a total of 3) images it can be seen ascending in the south-southeast in Virgo, and then crossing Bootes in the second image.

(click images to enlarge)

That same night I observed the payload, STSS-ATRR itself, much fainter, with the ETX-70. In addition, I saw Progress-M66 (09-006A), recently released from the ISS, and ISS itself. below is one of the images of Progress-M66, here seen crossing through Leo.

(click image to enlarge)

The Misty 2 decoy, USA 129, IGS 1B and more

Yesterday evening was a very clear evening. A bright moon lit the sky though.

Several objects were imaged. Two Keyhole satellites were captured: USA 129 (96-072A) and USA 161 (01-044A). For the first time this year, the Japanese IGS 1B (03-009B) defunct radar satellite was in range again, always a sure sign spring has arrived. Below are two images, of USA 129 and IGS 1B.

(click images to enlarge)

Among the HEO objects, the SIGINT USA 200 (08-010A) and the USA 144 deb/Misty 2 decoy (99-028C) were captured.

The latter is an interesting object. Launched in May 1999, a bright object from the launch was tracked by amateur observers (see story here). After some time it became clear from the orbital behaviour of the object, that it could not be a real operational payload. Rather, it is a piece of debris or a decoy meant to draw attention away from the real stealth payload. The object is bright, but probably small and very lightweight, and moving in a 2700 x 3100 km orbit. Below is the image I obtained on a pass of this object last evening.

(click image to enlarge)

Keyhole USA 161 flaring

On the night of April 1-2, the Keyhole optical satellite USA 161 (01-044A) flared brightly to mag. -2 just after shadow exit. I shot a whole series of images (yielding 7 positions), of which this is the first (exposure starting a few seconds after flare maximum):

(click image to enlarge)

The same evening I also captured the Keyhole USA 129 (96-072A). HEO objects imaged were the SIGINT USA 200 (08-010A) and two brief glints by NOSS 2-3A (96-029A). The Russian Kosmos 2392 (02-037A) was captured as a stray on the USA 200 images.