Sorting out the confusion: USA 161 and IGS 8R

Okay, so yesterday considerable confusion arose about the current orbit of USA 161 (see previous post). This was due to the (luckily shortlived) confusion between two objects: the real USA 161, and a Japanese spysat that was briefly mistaken by me for USA 161.

The object which I photographed during the night of May 30-31 and which Björn Gimmle photographed from Sweden on April 22, turned out to be not USA 161 but, as Cees Bassa pointed out, another classified object we had "lost" in the winter blackout: IGS 8R (2013-002C), a Japanese radar imaging satellite launched early 2013.

So the image below actually shows IGS 8R flaring brightly, not USA 161 as I initially thought:

click image to enlarge

Luckily, Russell Eberst in Scotland observed the real USA 161 on June 1. Together with the observation by Leo on May 23, this means we do have an idea of the current orbit of USA 161 now, although further refinement through more observations is necessary. What is clear, is that USA 161 still is in the same orbital plane it was in when we lost it in August 2013. It's RAAN difference with the primary East plane KH-11 USA 224 is still 20 degrees, and it's orbit is sun-synchronous and about 385 x 393 km (these are approximate values which are subject to change, as the current orbit is preliminary and needs some refinement with more observations). The current KH11 Keyhole/CRYSTAL constellation now looks like this:

The short-lived confusion of yesterday could arise because both objects (IGS 8R and USA 161) currently move in a similar orbital plane. This can be seen in the image below, where the IGS 8R orbit is yellow and the USA 161 orbit is light grey:

This is the kind of confusion that can arise when multiple objects who's orbit have not been recently updated, move in a similar orbital plane. It does not only happen to us amateur trackers: even the professionals at JSpOC sometimes confuse objects.

Actually, this situation ended positive with a double recovery: that of USA 161, and that of IGS 8R.

Topex/Poseidon flaring

Monday evening was clear. I targetted the KH-12 Keyhole USA 129 - it is expected to manoeuvre one of these days.

While watching it (and photographing it), a bright mag. +0.5 flash occurred close to it, followed by another one and than a longer +1.5 flare. It turned out to be the malfunctioned US-French Oceanographic satellite Topex/Poseidon (92-052A), which I have observed flashing before. It malfunctioned in 2006 and since has started to tumble.

Below is the image showing both USA 129 and Topex/Poseidon, the latter showing the three flares:

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The image yields this brightness curve, with peaks (two narrow and one broad) spaced 3.6 seconds apart:

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USA 161 new orbit finally established

The saga earlier covered here and here is finally coming to an end: it seems that the KH-12 keyhole USA 161 now no longer is escaping our detection.

The reboost on August 24 has provided our observer's and analysts corps with quite a challenge. After initial failures to recover it, the satellite was detected by several observers (including me) for a number of times in the early days of September. But in each case it was subsequently lost again and each new preliminary orbit solution put forward seemed to be wrong (see the two posts linked above in the introduction). Analysts were in despair, and observers confused.

Then Ted finally found a solution which seemed to agree with all observations and asked observers to search according to this search orbit early this week. Following this, Scott Tilley in the USA indeed recovered the object in a position much as predicted by Ted's solution, with Russell Eberst in Scotland following suit.

The now established orbit is quite different from the earlier search orbits. Instead of the perigee having  been raised, it turns out that it has been lowered, with the perigee 40 km lower and apogee 120 km lowered.

Rich batch of objects

The night of 13-14 September was a very clear one. The near-full moon was low in the sky and the sky very transparent.

I hauled a rich batch of objects, including 8 positions on the KeyHole USA 129 (96-072A), the Lacrosses 4 & 5, (00-047A & 05-016A), and the NOSS duo's 3-1 and 3-2 (01-040 A & C, 03-054 A & C).

USA 129 made a magnitude 0 flare at 20:19:20 UTC. The descending part of the flare was captured on photograph.

(click images to enlarge)

IGS-es, USA 193, and other stuff during beautiful clear nights

SatTrackCam Leiden just experienced a few beautifully clear, dark & transparent nights. The result is a fine batch of positions on several objects, including Keyholes (USA 161), Lacrosses (3, 4 & 5), USA 193 and the old & new Japanese IGS-es. The latter include my first positions on IGS 4A/R2 (07-005A).

The first capture of the latter object was when I was waiting for its rocket launcher (IGS 4r/R2r, 07-005C) on the night of May 17-18. Suddenly a bright (+2) object appeared 2 minutes before 07-005C should, following a similar trajectory. I made a photograph and then found out it was the A component.

Due to a goof from my side I initially thought it was the optical satellite (due to it having the "A" designation, analogue to IGS 1A, 03-009A) and hence was surprised to find it was so bright. Only later I realized it is the (intrinsically brighter) radar sat.

Keyhole USA 161 (01-044A) was observed flaring on the 18th at 00:12:50 UTC (-1.5, slow) and 00:14:13 UTC (-1, short).

USA 193 (06-057A) was bright.

Lacrosse 5 (05-016A) was elusive. On the 18th, it initially was +2 low in the sky but then quickly faded beyond vision for much of the pass.

Below are trail images of the "new" IGS 4A/R2, it's rocket 4R/R2r cruising through Lyra, Lacrosse 3 cruising amongst the Coma cluster stars, and an Iridium flare in twilight.

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Composite image of a USA 161 pass

Below image is a composite of two 10.7 second images, 35 seconds apart, made during yesterday's USA 161 (01-044A) pass. It includes the flare image posted earlier.

The stitch of the two images was made with Hugin/PTStitcher, the same software I use for my daylight panorama images.

The flare effect is even more accentuated in this composite, and the wide angle (roughly 50 x 50 degrees) makes several constellations well recognizable.

The glare in the lower right corner is reflection from a lamp on the courtyard.

(this image is of course reduced in size and compressed compared to the original, hence the fainter stars are lost).

(click image to enlarge)

USA 161 flare, beautiful evening

Yesterday evening was very clear, thanks to a strong wind blowing the clouds away. I could observe until 3 am, when clouds came in again.

Highlight of the session was Keyhole satellite USA 161 (01-044A). It was very bright for much of its pass (about +2) and then flared to mag. -1.5 at 00:00:46 UTC. It was so nice to do that while the camera was open: image is below.

Other catches included Lacrosses 3 & 4 (97-064A & 00-047A) and IGS 1B (03-009B). One of the Lacrosse 3 images also captured a stray, which turned out to be the Kosmos 2292 SL-8 rocket (94-061B). Several other bright strays were seen, three of them flaring nicely, while preparing the camera.

I had USA 161 some 0.6s late, IGS 1B some 2.6s late, Lacrosse 4 some 0.4s late, and Lacrosse 3 some 0.3s early.

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Flares of USA 186, Lacrosse 3 and an Iridium

Another very clear evening in which the sky was so transparent that the moon was no real hindrance.

I observed 3 flares. Iridium 47 flared to mag. -1.5 in twilight at virtually the same spot as yesterday's -6 Iridium 25 flare. The picture is below.

At 20:52:23 UTC I saw USA 186 (05-052A), which was faint during the rest of its pass, flare to mag. -2 in the north. Alas not on photograph.

I was more lucky with Lacrosse 3 (97-064A) which flared to mag. +1.5 at 21:01:34 UTC while the camera was open (see below image, the bright star left is Arcturus).

I also observed IGS 1B (03-009B), on a zenith pass. It was faint again and irregular, quite unlike its visibility in earlier years.

I am very tired currently, but given the unusually clear skies I might try some additional observations this morning on the new IGS objects.

(click images to enlarge)

4 flares in 15 minutes

This morning and evening of the 22nd, I managed to catch a number of fine flares again, four of which occurred within a time span of 15 minutes:

- two Iridium flares (-2 and -5, by Iridium 61 and 03 resp.);
- two USA 186 flares (-0.5 and 0), 20:44:33 and 20:45:26 UTC;
- a Lacrosse 4 flare (+1, predicted by Phil Masding), 20:41:54 UTC.

Images are below. The evening ended early when cirrus came in.

The Lacrosse flare was predicted by Philip Masding (just like the Lacrosse flare of yesterday) to within 2 seconds of time exactly.

Flares never bore me, they are always exciting to watch, and even more so when they occur at random and are so nice to do so while the camera is open....

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A timing re-calibration and another flare bonanza

Following the discovery of time discrepancies having crept into my results, I have added a -0.35 second correction as of last evening's results. The results now come much more in-line again.

In order to test this I targeted a number of objects last night, including some Iridium passes. Apart from two Iridium flares, I managed to catch some flares of classifieds again.

Here is Keyhole USA 186 (05-042A) flaring to mag. 0 in the east at 20:21:25 UTC:

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Philip Masding notified me ahead of a possible Lacrosse 4 (00-047A) flare at 21:46:15 UTC: I observed it flaring to mag. +0.5 at 21:46:17 UTC:

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USA 129 (96-072A) flared to -1 at 20:34:30 UT in the sickle of Leo, alas inbetween two images, and in general was bright in the first half of its pass:

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ISS made a nice pass close to Procyon in deep twilight. The wisps of cirrus still present at that time would rapidly dissolve:

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Timing errors and a mag. -5 IGS 1B flare

After the unexpected METOP-A flare of yesterday evening, I was surprised by another unexpected flare. And what a flare: it concerned the failed Japanese radar satellite IGS 1B (03-009B) flaring at about 21:06:20 UTC to magnitude -5!

It happened after I had taken a photograph of IGS 1B and was in the process of moving my tripod to another corner of the courtyard. I suddenly saw it flaring so brilliantly with a distinct yellowish colour and my jaw dropped. I didn't get the chance to aim and get a shot of it.

I have never seen IGS 1B do this before. Together with the somewhat irregular brightness behaviour in past evening sightings, I think it underlines that it is tumbling out of control.

On a less positive note, I seem to have developed a time lag in my positions lately. They seem to be about 0.35 seconds too late in general. All positions produced from now on will incorporate a 0.35s correction therefore and we'll see whether things get in line again.

The most likely source of the timing error is in the camera (another much less likely option is in the DCF77 signal). Indeed I recently did access my camera with other software than usual, which seems to have done something to my settings.

The timing accuracy keeps being a head-ache and the bottle-neck of the technique I employ, together with the effects of random noise (and the noise suppression routine) in the image.

Yet for now my current equipment is all I can afford, so I'll just have to do with it.

Below is another image of yesterday, showing Keyhole USA 129 (96-072A) crossing at mag. +1 close to the coma cluster (here shown at reduced resolution, so some of the fainter stars are lost).

(click image to enlarge)

Bonus flare of unknown (=Metop-A) with USA 129 (UPDATED)

"Something" just produced a fine mag. -1.5 flare only a few degrees from USA 129. I have not identified the flaring object yet. I could see the two cruise up with each other on roughly parallel tracks, a few degrees apart, USA 129 at +2.5, in Ursa Major. The flarer was leading and produced the flare at 20:12:10 UTC. See image below. The fainter trail is USA 129.

USA 129 itself (I believe) produced a flare of mag. 0 low in the east at about 20:11:00 and remained bright for tens of seconds after that. I catched it still being +1 some 20 seconds later.

More later, including (I hope) the flarer ID after I have measured the image and have dan an ID run with the positions.

Update: the flaring object is identified as Metop-A, 06-044A. With thanks to Russell Eberst and Arnold Barmettler.

(click image to enlarge)

Flare Galore! And IGS 1B tumbling?

Flare Galore this evening! Three objects were observed flaring: keyholes USA 186 (05-042A), USA 129 (96-072A), and Lacrosse 4 (00-047A).

The USA 186 flare was spectacular, see the image below. It was a complex double flare. First it very slowly flared to mag. -1.5, peaking round about 20:53:00 UTC. When it was still fading from that flare, a second very short flare was seen at about 20:53:11 UTC. This flare terminated very suddenly, the sat becoming faint in an instance.

Below image shows it all. The peak of the first -1.5 flare coincides more or less with start of the exposure and is at down left (movement is from down left to upper right). The second flare can be seen at upper right. It ended very abruptly with the sat going to naked eye near-invisibility almost at an instance. update (19/04/07): the faint trail extension I thought was real, turns out to be an image artifact.

(click images to enlarge)

Shortly after this, USA 129 flared as well, albeit more modest than USA 186 ten minutes earlier. It reached about mag. +1 at 21:03:30 UTC. The image below shows it fading directly after the flare peak.

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The third flare of this night was produced by Lacrosse 4, and predicted to me by Philip Masding. His prediction was for 21:37:34 UTC: it flared at 21:37:37 UTC. It was a modest flare only. The image is below, the brightness modestly peaks in the second part of the trail.

(click image to enlarge)

This evening I finally successfully observed and captured IGS 1B (03-009B), the Japanese radar satellite that recently reportedly failed. It made a shadow exit at 23:52:50 UTC and was of mag. +2 immediately following that. In the next minute it slowly, irregularly but clearly varied in brightness with an amplitude of about 0.5 to 1 magnitude.

This is quite unlike its steady brighness in past years, so it appears that after the power failure its attitude is now out of control and it is tumbling.

In the image below it is fading, shortly after the end of the exposure it shortly gained brightness again.

(click image to enlarge)

In addition to this all I also watched and photographed a fine pass of the International Space Station around 20:32 UTC, and spotted and photographed a bright stray object near 20:51 UTC while waiting for USA 186: I still have to identify this object as I have not measured that image yet.

Lacrosse 2 running early

Lacrosse 2 (91-017A), the oldest in the Lacrosse (Onyx) SAR-satellite series still in orbit, is running increasingly early. Yesterday evening it already was over 7 seconds early and clearly off-track relative to a 4 day old elset. Is it going down for a de-orbit?

Yesterday evening saw very clear skies. I gathered a nice batch of data: two images (4 positions) on Lacrosse 2 (91-017A), two images (4 positions) on Lacrosse 3 (97-064A), and three images (6 positions) on USA 129 (96-072A). Plus in addition to this, I catched a stray in one of the Lacrosse 3 images, which turned out to be a 22-year-old Russian rocket booster, Kosmos 1689 Rk (85-090B, #16111).

Below is one of the three images I shot of USA 129.

This evening I skipped tracking activities. I am not feeling well and decided to take some rest instead.

(click image to enlarge)

Flaring Keyhole USA 129

There was cirrus in the sky in daytime, persisting after sunset. Only after 9 pm local time, the sky had cleared enough from haze to attempt photography. This left only one target, USA 129 (96-072A, #24680), a Keyhole imaging satellite.

It made a zenith-pass near 20:21 UTC during which it put on a spectacular show.

As it cleared the edge of the roof and came into my view in the zenith, it was very bright and clearly flaring. It must have been around mag. 0 to -1, peaking near or before 20:21:20 UTC. When my camera opened it was already past peak brightness for several seconds but still bright, gradualy fading. The image is below.

Obtained two positions from the image. My timings suggest it was 1.15s early with regard to elset 07066.85705303

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A Keyhole and two Lacrosses

Another clear evening last night. I managed to catch one KH and two Lacrosses.

The KH was USA 129 (96-072A). It appears as two rather faint trails on two images: the starting point on the first trail is behind the building. I have it running 0.7s early relative to a 2-day-old elset. I obtained 3 positions

Lacrosse 2 (91-017A) was as much as 1.5s early and 0.1 degree off in cross-track relative to a similar aged elset. I obtained 3 positions.

Lacrosse 3 (97-064A) by contrast was pretty much on-time and on-track. It made a nice bright trail. It briefly and modestly flared up to maybe +1.5 at about 19:49:45 UTC, just before shadow entry. I obtained 2 positions.