Early March observations and pulsing (?) brightness of the STSS Demo-1

I am well behind on reporting on my March observations so far. I observed on the evenings of 1, 2, 3, 6, 7, 9 and 16 March. Observed objects include:

The Lacrosses 2, 3 and 5; NOSS 3-1; USA 200; USA 129; The USA 144 decoy; STSS demo 1 and demo 2; and a number of strays.

The KH-12 KeyHole USA 129 (96-072A) is a favourite target, now it has come out of it's winter hiding. I observed a number of flares from this satellite again (alas all while the camera was closed). Below are two trail images from 7 and 16 March, showing it rising (16 March) and decsending (7 March):

click image to enlarge

The STSS Demo 1 & 2 objects (09-052A & B) were also frequently targetted. On March 16, I captured a shortlived pulsating brightness behaviour for STSS Demo 1 that is very similar to the shortlived pulsating behaviour I captured for the other STSS Demo object (demo 2) on February 20. Liek on that occasion, the behaviour is present in the first 2 seconds of one single trail image (out of a series of several). below is the image showing the pulses in the early part of the trail (top), and below that are the brightness diagram, and a diagram of the delta T between the pulses (read and compare also the report for February 20). The period for the early part is a flat 0.16s.

I do not want to exclude, even though I cannot explain it, that it is some instrumental effect. This because it is again in the first 2 seconds of a trail.

The Lacrosse 5 "disappearance trick", and a BWGS meeting

On Saturday 26 September, a small number of BWGS satellite observers gathered at the house-boat of Leo Barhorst (Cospar 4253) at Almere. Present were, besides Leo Barhorst, BWGS president Bram Dorreman and me. A number of active BWGS observers alas could not come, hence the rather small group this time.

In the afternoon we exchanged some information, looked at some software, my collection of "black space program" mission, launch and unit patches, and Leo's collection of space-related postal stamps. I demonstrated how I astrometrically measure my satellite photographs for positions, and how I get brightness curves from an image.

The plan was to try some joint observations that evening (we could stay for the night at Leo's boat), and as it was sunny, we started preparations in the early evening. I took below photograph of Leo (seen frontal) and Bram (seen on the back) while they were making their preparations

click image to enlarge

The sky was not perfect (and would progressively deteriorate later that evening). From a small green a few tens of yards from Leo's boat, we started by watching Iridium 80 flare to mag. -3.5 close to epsilon Cyg in the eastern wingtip of Cygnus. I took the picture below, a 10-second exposure with the EF 100/2.8 Macro USM:

click image to enlarge

Immediately after that I rushed to re-aim the camera and capture the USA 144 decoy (99-028C) passing close to vega in the next minute. Predictions had put the track just west of Vega, and while Bram and Leo were watching there with binoculars I made a series of images. Strangely enough, Bram and leo did not pick it up: and the reason was, after a look at my photographs, that it passed east of Vega, not west! After a puzzled "huh?!?" it dawned upon me: the coordinates of my prediction software were still set on my Leiden locality!

Next up were the objects related to the recent launch of a Russian Meteor weather satellite. Bram and Leo indeed picked one up with their binoculars.

Shortly after that, we watched a nice pass of the SAR Lacrosse 5 (05-016A) with the naked eye. As we watched it, it did it's infamous "disappearance trick" again. It did so during an exposure, that captured the quick loss of brightness very well. It was the first time I imaged the phenomena with my Canon EOS 450 DSLR. It yielded this very nice diagram of the brightness variation (constructed from two images):

click image to enlarge

Note how quick the brightness drop is (it takes a mere 4 seconds) and how sharp the turnpoints in the diagram are.

Next up were passes of the KH-12 optical reconnaisance Keyhole USA 186 (05-042A), which briefly attained naked eye visibility and was of course photographed; and the NOSS 3-3 duo (05-004A & C) which were faintly visible to the naked eye as they crossed Cygnus, and yielded two very fine pictures, one of which is below:

click image to enlarge

Note the difference in brightness between the A and C components. (note: I mistakenly labelled the C component as 'B' in the image...)

After this, Leo and Bram observed the NOSS 3-3 rocket, which is a flasher. As the sky quality rapidly deteriorated, we called it quits after that and went inside to reduce the observational data.

It was nice to meet and observe together. Leo was a perfect host, and his cat Bankie kept my feet warm later that night.

The past week saw several bright evenings, yielding a rich haul of satellite positions. Observations were done in the evenings of September 16, 17, 20 and 21. Data were obtained on some of "the usual suspects": the KH-12 Keyholes USA 129 and USA 186, the SAR Lacrosse 2, the HEO objects USA 184 and USA 198, and the USA 144 decoy.

Both KH-12 Keyholes USA 129 and 186 slowly flared to -1 at September 16th: 96-072A at about 19:44:27 UTC in the southeast; 05-042A at 21:01:46 UTC in the northwest.

USA 129 showed another bright slow flare peaking about 20:00:51 UTC on 17 Sep, just after the end of an exposure. I captured the rising part of it.

Below are two pictures of last evening (21 Sept), showing the KH-12 Keyhole plus a faint stray near M31, the Andromeda galaxy: and showing the USA 144 decoy passing close to the ELINT USA 184. The first image was made with the EF 50/2.5 macro lens, the second with the EF 100/2.8 macro USM lens.

click images to enlarge

More observations from last evening

The clouds that threatened last evenings HTV-1 observation (see previous post) moved out somewhat later, allowing me to bag several objects.

I observed both of the evening KH-12 Keyholes, USA 129 (96-072A) and USA 186 (05-042A). USA 129 was very bright (mag. -1) while ascending through Aquila low in the south, yielding some very fine pictures of which this is the first:

click image to enlarge

The other KH-12, USA 186, featured a slow bright flare to mag. -2 around 21:10:35 UTC (12 Sep), alas outside the camera view.

Some high altitude objects were captured again as well: the by now familiar USA 184 ELINT/SBIRS (06-027A), the SDS-3 USA 198 (07-060A) and the USA 144/Misty-2 Decoy (99-028C).

I recently obtained the launch patches of both USA 184 and USA 198:

click images to enlarge

The USA 198 patch (bottom) shows the satellite constellation it is part of: two Molniya orbits and a geostationary orbit. The Latin text roughly translates to "Beware of our Sting".

Molniya orbits and a Keyhole flare again

The evening of September 10 saw more than a nice Space Shuttle pass (see previous post) and the ISS.

In fact, it was a prolific evening which yielded data on the Lacrosse 2 SAR (91-017A), the USA 186 KH-12 Keyhole (05-042A) and two objects in Molniya orbits: the ELINT and SBIRS satellite USA 184 (06-027A) and the SDS-3 communication satellite USA 198 (07-060A).

USA 184 was imaged in two sessions 1h 45m apart. It is interesting to see the effect of it moving towards its apogeum (see below: in these images, which are on the same scale and at full pixel resolution, 1 pixel equals 10" (arcseconds)): while during the first session the satellite still creates a recognizable trail in the 10 second exposures (taken with the EF100/2.8 Macro USM), it appears as an almost static stellar object in the exposures taken 1h 45m later:

click image to enlarge

The Keyhole USA 186 flared brightly to -1 at about 20:25:43 UTC, just before the start of an exposure. I captured the descending branch of the flare. As I had mispointed the camera in haste, the satellite unfortunately runs out of the FOV (the sat is moving from right to left on the image):

click images to enlarge