Difficult Lacrosse 5 flare (?) observation

Tried to observe the 01:11:48 UTC predicted Lacrosse 5 (2005-016A, #28646) flare last night predicted for my location by Phillip Masding.

Observing conditions were very bad, as I had to watch the sat through broken cloud cover. I cannot 100% positively say I saw it flare in the sense of seing it rise and fall in brightness: all I can say is that it was very bright at the flare time, being about mag.-1 (when I first picked it up lower in the sky at 01:10:00 UTC, it was about mag. +1.5).

Photograph below (01:11:46.1 - 01:11:56.8 UTC). The photograph gives you a good idea of the difficult observing conditions.

It is overcast with heavy rainshowers here at the moment, so I am affraid this evenings possible flare is lost for me.

(click image for larger picture)

Lacrosse 5: now you see it, now you don't....

Phillip Masding had predicted a possible Lacrosse 5 (2005-016A) flare for me for last night at 21:50:22 UTC:

Flare Results for Flight Mode YVV Panel Angle 33°
12. SAR MA 2.97104043228698 at 31/07/2006 21:51:22 Alt=74.2391395227923

However: it did not flare, but disappeared again instead....

I picked Lacrosse 5 up at about 21:50:00 UTC near Bootes/CrB. It was mag. +2.5 brightening to +2.0 in the next half minute or so.

Somewhere around 21:50:45 I started to look at my clock to trigger the camera countdown at 21:51:07 UTC. When I looked up again at 21:51:09 or so, it already was gone. It did not re-appear.

The photograph (21:51:18.1 to 21:51:28.8 UTC) shows no trail at all, meaning that at that time it must have been fainter than +3.5. Would it have been as bright as it was a 21:50:00 to 21:50:45 it would be visible on the image, and certainly if it subsequently would have flared.

There was some thin cirrus in the sky, but the area where it should have flared was clear and faint stars are visible on the image.

Two classified SAR birds in one image

(click for larger image)

Under far from optimal conditions I was able to capture the trails of two
classified Radar birds on one image, only a few degrees apart: IGS 1B (2003-009B, #27699) and Lacrosse 4 (2000-047A, #26473).

This is a crop of the original image, reduced in resolution. In the center of
the image is Corona Borealis.

As the sky was very hazy the original colour image was quite fogged, so I
transferred it to B/W and then played with the contrast a bit to make the trails
stand out better.

It became overcast shortly after so no chance to capture the odd bird Lacrosse 5
again. My photograph of the 26th sparked a whole series of communications about the cause of the "disappearance trick" and the configuration of the Lacrosses in general.

Lacrosse' 5 odd behaviour

Last night Lacrosse 5 (2005-016A, #28646) performed its amazing "disappearance trick" again, just as it did in March. This time however, it did while the camera was open: it was caught in the act of disappearing:

(click image for enlargement)

Movement is from bottom to top here. Lyra is well recognizable. You can see the trail quickly fading out (it takes maybe 2-3 seconds in total). In fact, the trail should end between 13 & 16 Lyr (the two stars above the trail) on this 10.7 s exposure. Also note that the satellite was nowhere near shadow entry at this time.

As Ted Molczan and Allan Thomson have stated, the suggestion is that a dark "something", perhaps an antenae panel, blocks view of the main body. At any rate, this behaviour is peculiar to Lacrosse 5 and not shown by Lacrosse 2, 3 & 4. In fact, Lacrosse 5 deviates in a number of things:

* it is brighter (visually and photographically);
* instead of red-orange it is yellow in colour;
* the other Lacrosse-birds don't do the "disappearance-trick"
(instead, they show short flares)

To which Ted Molczan added:
* It is also the first not to employ a frozen orbit.

Other observations I did the past days, observations which due to various reasons I did not come to discuss here yet were:

- Lacrosse 4 on July 23rd
- IGS 1B and Lacrosse 3 & 4 on July 21st
- Lacrosse 3 on July 18th

Clear skies continue

Clear skies continue, so last night I have been tracking again. For the first time in several weeks a Keyhole let itself be imaged again: USA 161 (2001-044A)was imaged as a very faint trail. No flares this time. Lacrosse 3 (1997-064A) made a nice bright crisp trail, and I captured IGS 1B (2003-009B) while it was cleearing the roof.

Staying up late (untill after 2 am) is taking its toll now though, so the next days I might opt for sleep instead.

Lacrosse 3 and 90-046B as a stray

Catched Kosmos 2082rk (90-046B) as a bright stray together with Lacrosse 3 (97-064A).

NLC's and satellites

Last Friday evening saw a major display of Noctilucent Clouds here. Casper ter Kuiile sent out the first alert around 23:00 CEST through our DMS Alert Network. I made a short stroll throught the city untill I found a spot with visibility low enough down to the horizon. Nice, I hadn't seen the eery blue glow of NLC's for a few years.

Later that night I captured Lacrosse 3 and Lacrosse 5 Rk.

A nice and predicted Lacrosse 3 flare

Philip Masding predicted a flare of Lacrosse 3 (25017, 97-064A) for my site for this night (jul13-14), 00:22:22 UTC.

I watched Lacrosse slowly flare to mag. 0 at 00:22:27 +/- 1s UTC. So his prediction was correct by an error of only 5 seconds!

Below is the image I shot of the flare (click image for larger size). Earlierr this night I saw USA 161 briefly flare too.

Tracking again, and imaging nightfall in time-lapse

After a period with clouded evening skies and/or no opportunity to track, last week saw some opportunities again. Yesterday and the day before I obtained images on Lacrosse 3, as well as IGS 1B, the latter having manouvred acoording to Pierre. I hope the good weather prevails, because Philip Mading mailed me a whole list with Lacrosse 3 flare predictions which I want to put to the test.

Yesterday night while tired and typing in the designations, I made a typo in the Cospar code for Lacrosse 3, which was diligently spotted by Russell.

Meanwhile I am still hooked by the time-lapse photography bug. Below is a movie showing nightfall over Cospar 4353, shot yesterday evening. Compressed into an 48 second movie is 4 hours of real time, starting 2.5 hours before sunset and ending 1.5 after sunset. The movie was made from 711 individual photographs.

Another Time-Lapse movie

Another time-lapse movie which I made this afternoon. It is 1.5 hours (264 photographs) of moving cloud-scape shot between 13:10 and 14:40 CEST, compressed into a 18 second movie. Good Bye Blue Sky...see the dark clouds move in again... First experiment with adding some music too.

And obviously, with this type a dynamic atmosphere, there is little satellite tracking to be done..

Time-lapse of frontal cloud cover arriving

I am experimenting a bit with time-lapse photography. Thanks to the digital revolution, this is quite do-able nowadays with the help of a digital camera, a lap-top (or pc), and some freeware and shareware available on the web.

Below 18 second .avi movie was made with my Canon Digital Ixus 400 hooked up to my lap-top, which thus controlled its operation. 181 pictures were taken over a timespan of 1.5 hours (so: one each 0.5 minute).



The attempt initially was to capture the clour-play of sunset on the high altitude cirrus clouds. But right after I started the series, a frontal low cloud cover came in.

Impressive clouds...

A thunderstorm developed here this morning. A few hours later, the clouds below appeared over the town, signifying the very unstable air. This picture was shot by me today (5 July 2006) at 13:00 CEST (11:00 UTC) from the Beestenmarkt, Leiden. I have tried to identify the type, and the best I can come up with is Stratocumulus opacus mamma.

Progress M-57 observed

The Progress M-57 supply space-ship was launched from Russia in the afternoon of the 24th, heading to the ISS.

Based on a predicted TLE by Bob Christy I managed to see it passing near the zenith in bright twilight at 21:14 UTC. It was about mag. +1, easily visible with the naked eye notwithstanding the twilight, and steady. It was moving very fast, due to its still low altitude. It was very nice to see.

In a communication with Leo Barhorst, who observed the spaceship and its rocket on the same pass, it was resolved that the object I saw was indeed the Progress and not the rocket, as Leo observed the rocket to be flashing while Progress was steady (as was the object I saw).

Because of the still bright sky, no photography was attempted.

USA 161 flashing, Lacrosse 4 and a stray

A late report on the observations on the nigh of of June 19-20th. I was too tired yesterday to write an entry.

Highlight of the nigh was capturing Keyhole USA 161 (01-044A, #26934) while it was giving a series of very short bright mag. -2 flashes (at least 3 in about 2 minutes time). I captured two with the camera, the best of which is below (arrow points to flare which almost looks like a star, a faint trail can be seen to the upper right).



Above picture yielded two positions, indicating USA 161 was on-time but slightly off-track (0.05 deg in cross-track).

flash 1: 23:22:06 UTC ± 1 s
flash 2: 23:22:??
flash 3: 23:23:35 UTC ± 2s

I also captured Lacrosse 4 again, and a stray, which turned out to be Kosmos 1602 (84-105A). The observations on the latter suggests there might be a timing error in my Lacrosse 4 data of this night. The sat was on-track (cross-track error max. 0.01 deg).

The timings keep being the biggest bottle-neck. It will only be resolved if ever I come in the financial position again where I can allow myself a better camera that can be triggered directly from the lap-top.

USA 116 keyhole flare

Last night at 1:06:25 UTC (3:06 am local time) I observed a nice mag. -2 flare of Keyhole USA 116 (1995-066A, #23728). The onset of the flare was captured by the camera, the image yielding two nice positions.

This was the first time I imaged USA 116. The obtained positions are on-track and at best some 0.1s early.

I also captured Lacrosse 4 (2000-047A), as I did a few nights earlier, on the 12th June. The June 12 data were "only"0.45s late relative to a 20-day old elset, and some 0.17 deg off-track in cross-track.

Last night's 2000-047A data are some 0.15s early, and again off track (about 0.12 deg. in cross-track) relative to an updated 3-day old elset (elset 06165.01332539).

Catched a mag -1.5 Lacrosse 2 flare

The haze in the sky was less last night than previous nights. At 21:54:48 UTC I cached Lacrosse 2 (1991-017A, #21147) flaring too about mag. -1.5, while the camera was open. I produced the very nice pcture above, as well as some good positional results. Satellite movement is from lower left to upper right.

The trail is very well defined on the image, while overall star positional inaccuuracy is only 22". Relative to Mike's 1-day old elset 06159.92449946, delta T is +0.02 resp. -0.01 seconds. The crosstrack error is 0.05 resp. 0.06 degrees. This is larger than usual and given the very fine results overall, this cross-track deviation must be a real deviation and not a measurement error imho.

Lacrosse 2
1 21147U 91017A 06159.92449946 0.00000080 00000-0 11747-4 0 06
2 21147 67.9874 90.2300 0005500 236.6210 123.3790 14.75395581 05

LAST OB : 161

STA____ AZ____EL_____ASP____XTRK__deltaT Perr
4353___348.35__73.19__76.50__0.05__0.02___0.050
4353_____3.37__78.76__82.47__0.06_-0.01___0.057

sum 0.05354

Clear skies at last...with a -2 Lacrosse 5 flare

A clear evening again after many days with rain and hailstones. Slight haze but otherwise good, +10 C. I managed to capture IGS 1B (03-009B) and Lacrosse 5 (05-016A).

Lacrosse 5 (05-016A) briefly and unexpectedly flared to mag -2.0 at 22:02:20 UTC (+/- 10s) while I was preparing the camera. It made a distinctly yellow impression in colour. Food for Philip!

03-009B was 2.8s early relative to elset 06135.93706251, while 05-016A was 0.4s late relative to elset 06141.91063216

At this moment, the sky is overcast again.

The weather, weather data for Cospar 4353, and the Navy Googling for USA 129

Weather is still bad here. Yesterday afternoon it looked like I could do some observations, as it nearly completely cleared, but in the evening fields of cumulus came in again. At this moment, it is raining and we even had hailstones today. The bad weather the past week means I could not test Phil Masding's predictions for several Lacrosse 5 flares by observing them.

On another note: last weekend saw my weather station becoming operational. I purchased a small electronic (radiographic) weather station through ebay recently. After some sawing, hammering and painting activities resulting in a 1.5 meter pole with an half-open small casing on it, the sensor is now on the courtyard and sending its temperature records to the receiver in my home. A daily report of measured maximum- and minimum temperatures and air pressure at Cospar 4353 can now be found here.


I had the US Navy visiting my webpage today. Someone there Googled for "USA 129". I have more military visits every now and then.

24/05/2006 17:30 CEST temp. 10.1 C, air presssure 1016 hPa

Meeting other satellite observers

Yesterday I travelled to Belgium to meet some other satellite observers out of the BWGS at the home of Bram Dorreman. The meeting was as well a BWGS meeting, a birthday meeting for Bram Dorreman, and a meeting to celebrate his 40th anniversary as a satellite observer.

Leo picked me up by car at Vleuten and we then continued to fetch Wim and a Belgian lady Marieke. Other joining at Bram's house were Tristan and Kurt. The meeting was very pleasant and informal, we were cared for very well in terms of drinks and food by Bram and his wife. For me, this was the first time I met other satellite observers except of Bram.

Wim brought some bulletins out of the "old box" with him. Kurt demonstrated the latest development of his internet PPAS database. Bram brought us back to the early days, by demonstrating the 'ancient' and time consuming graphic technique for predicting satellite passes of yesteryear. Ah, so much has changed...

It was a fun meeting.

The weather is very bad here the past week. Heavy rain showers and thick cloud cover.

Yesterdays Lacrosse 3 data

Russell Eberst reported data for Lacrosse 3 (97-064A) from last night as well, from a later pass. Our results quite agree:


STA___XTRK___deltaT___Perr

4353___0.04___-0.83___0.450
4353___0.02___-0.74___0.416
2420___0.02___-0.86___0.448

(STA = station, with 2420 being Russell; XTRK = cross-track error in degrees; deltaT = timing error in seconds, with negative meaning 'early'; Perr = positional error in degrees)

Relative to elset 06125.89779354, the satellite was some 0.8 seconds early.