Saturday, 14 October 2006

Warning about the orbit constellation plots

Hmmm, having played a bit more with it, it is clear that WinOrsa does not quite plot artificial earth satellites at the correct geographic subsatellite points.

The relative orbital constellation as such seems reasonably okay though. I think it models only using gravity (its software for modelling solar system object orbits after all) and not drag, hence the satellites get plotted at wrong positions in their orbits .

So be careful with the 3D plots I recently posted. The relative orbit orientations seem okay, but the absolute positions of the satellites not.

Note added 16/10: WinOrsa author Pasquale Tricarico today confirmed me that only gravity is modelled and not (yet) drag. This will hopefully be included in a future release. That would be cool, as the 3D graphic output of the software is great.

Thursday, 12 October 2006

Spysat orbital constellation plot: NOSS

Orbital constellation of the Naval Ocean Surveillance System (NOSS) satellites, duo's and trio's of satellites for tracking ocean shipping (more info here).


Wednesday, 11 October 2006

Coincidence, or clever Korean timing?

Coincidence, or clever timing by the North Koreans? When North Korea conducted its alledged atomic bomb test last Monday at 01:36 UTC, it almost seems as if they waited untill the test area was just outside the footprint of the Japanese IGS 1B, detonating it within minutes of it passing by.

IGS 1B (03-009B, #27699) is a Japanese high resolution radar reconnaissance satellite, one of the primary purposes of which is to keep an eye on North Korea.




Tuesday, 10 October 2006

Some spysat orbital constellation plots (KH-12 Keyhole, Lacrosse and IGS)

Plots of the orbit constellations of the American KH-12 Keyhole optical imaging satellites and Lacrosse (Onyx) synthetic aperture radar satellites, and the Japanese IGS optical and radar satellites.

(see here for details on how the plots were made and additional plots)

(click images to enlarge)








This plot shows how the IGS satellites keep an eye on North Korea:

(click image to enlarge)

Picture fom last weekend

One of the pictures from last weekend, showing the trail of Lacrosse 5rk (05-016B, #28647), the still orbiting rocket stage of the Lacrosse 5 (05-016A) launch. The 'W' of Cassiopeia is well recognizable to the left of the trail (this, like all pictures on this blog, is a reduced resolution crop of part of the original image)

(click image to enlarge)


Sunday, 8 October 2006

Unexpected clear sky: Lacrosse 3 & Lacrosse 5rk

It rather unexpectedly cleared in the evening. Good transparent sky.

A first pass (18:34 UTC) of Lacrosse 3 (97-064A, #25017) was captured but the trail too faint to measure. More luck during the 20:14 UTC pass, when it was bright just before going into eclipse. Two points, on-time but perhaps slightly off-track (0.05-0.07 deg) with regard to elset 06278.76700984.

Got two pictures of Lacrosse 5rk (05-016B, #28647), hence 4 points, it was bright, nice pass. It was some 0.4 sec late and on-track with regard to elset 06277.75736727.

With a temperature of only 11 C outside, it was chilly.

Quite a lot....

Below are two plots I constructed showing the orbits of all 170 amateur tracked classified objects (operational and defunct satellites and rocket boosters) from Mike McCant's classfd.tle. Quite a lot, isn't it?

The images were made with Pasquale Tricarico's WinOrsa orbit software

(click images to enlarge)





Update: some more plots of a few individual LEO sat orbit constellations here

Wednesday, 4 October 2006

Bad luck

I was having bad luck this evening, quite some bad luck... First, cloud cover prevented me from imaging the early passes of Lacrosse 2 & 3 and Lacrosse 5Rk. Then it cleared, but just as I pressed the trigger button to image the next pass of Lacrosse 3, the camera shut itself off due to a battery problem. Ten minutes later, clouds won the race for a patch of clear skies with Lacrosse 5Rk by a margin of only a minute. Damn.

Saturday, 30 September 2006

Lacrosse 3 & Lacrosse 5rk cruising up together

This evening I caught Lacrosse 3 (97-064A, #25017) and Lacrosse 5rk (05-016B, #28647), the rocket stage of the Lacrosse 5 launch, cruising up together in the sky in close proximity and same direction.



(Click image for larger picture)

I managed to get only this one picture, as the battery of my camera was empty and hence my camera shut off after this image. Lacrosse 3 was about mag.+2, Lacrosse 5rk about +2.5.

There was some cirrus in the sky. Contrast has somewhat been enhanced in the posted image crop, to enhance the trails. Stars visible are mainly from Ursa minor and Draco, Polaris is in the upper right corner of the image.

97-064A was only 0.1s late relative to 6-day-old elements (elset 06267.82859916). 05-016B was 2.2s late relative to a week old elements (elset 06266.84118421).

Monday, 25 September 2006

Illustrative diagrams




These two diagrams I prepared this weekend from recent observational data by stations Cospar 710, 2420 and me (4353) on KH-12 USA 186 (05-042A, #28888). They are compared to Mike's orbit elset 6261.8706146.

It very graphically demostrates the need for continuous orbital updates using our tracking data. As can be seen, data start to deviate quickly, due to orbital perturbations of the satellite, past the epoch date. Within 5 days after the elset epoch the satellite passes already 3 second early, a good degree off in position. This is why there is a continuous need for new tracking data.

Sunday, 24 September 2006

Lacrosse 2

A second front passed yesterday, bringing a few raindrops in the morning. Around dusk it cleared for a while, but the sky remained very hazy. Nevertheless managed to image Lacrosse 2 (91-017A, # 21147). It was only 0.1s early and on-track, no surprises. A quickly deteriorating sky prevented other tracking attempts.

Friday, 22 September 2006

USA 186 Flare Galore

Yesterday evening at the 20:44 UTC pass I was treated to two nice flares by KH-12 Keyhole USA 186 (2005-042A, #28888). Both flares happened while the camera was open (on two consecutive images). The second flare at 20:44:43 +/- 2s UTC amidst the stars of Ursa minor was brilliant, reached magnitude -2 and took over 10 seconds. The result was the fine photograph below:



(click image for larger version)

The earlier flare ( a glint rather) was near the zenith and a short one, reaching magnitude +1 at 20:43:46 +/-2s UTC with a duration of less than a second.



(click image for larger version)

The positions obtained from the photographs suggest USA 186 (05-042A) appeared 1.8 sec early and 0.06 deg off-track relative to elset 06261.87061463.

I almost lost these two observations! I was busy with answering fireball reports pouring in on a bright almost-daylight fireball that appeared at 17:35 UTC and in doing so lost track on the time. So at 20:42 UTC I suddenly realised a USA 186 pass was imminent at 20:44 UTC! I jammed open the window, slammed the camera tripod on the courtyard, slammed the camera n it and got two very lucky shots...!

I have two older observation runs to report as well.

On Sept 20 I catched a faint trail of USA 186, as well as a bright trail of Lacrossse 2 (1991-017A, #21147).

On Sept 18th I observed two other short glints of USA 186, one of which was photographed:

* 21:10:12 ± 2s UTC very short, mag. -1. Caught on photo, flare appears near-stellar

* 21:10:35 ± 2s UTC again very short, mag. +0.5

On the photograph with the 21:10:12 UTC flare, the trail is very faint pre- and post-flare. I obtained one position (endpoint of the trail seemed defined enough to measure).

Monday, 11 September 2006

Flare update and Cospar 4353 on Google Earth

Pierre observed in the same flarepath of USA 186 (05-042A) yesterday evening as the one that caused the flare I observed. From western France, he saw it flare about 40 seconds earlier than I did from the western Netherlands.

On an unrelated note: below is a Google Earth image where I have circled the location of SatTrackCam Leiden. The courtyard is well visible.

USA 186 flare, and is it manoeuvring?

KH-12 type Keyhole optical imaging reconnaisance sat USA 186 (05-042A, #28888) brightly flared to mag. -2 in the northwest at 21:13:06 ± 3s UTC. When I first saw it, looking up from triggering the 10 second camera selftimer, it was very bright, and it faded gradually as the camera opened (see image below). It was a very slow flare lasting tens of seconds, unlike the very brief glints I had observed so far from this satellite (e.g. report and photograph here).



(click image for larger picture)


It was as much as 9 seconds early and 0.10 deg off in cross-track with respect to 4 day old elset 06249.87384698, and 2.5s early with respect to Russel's observations 25 hours earlier: is it manoeuvring?

About an hour earlier I also captured another keyhole, USA 129 (96-072A, #24680). The trail was faint, the two obtained positions are about 1s early.

Sunday, 27 August 2006

Short observing session

After many days with heavy rainshowers, it cleared yesterday evening.

I did a short observation run: cut short alas by the return of clouds just before an IGS 1B zenith pass. I did manage to get data on Lacrosse 2 (91-017A),and observed two short bright glints by two Keyholes, USA 186 (05-042A) and USA 129 (96-072A). Lacrosse 2 appearred some 0.1s early.

2005-042A glinted to mag. 0 during less than a second at about 20:01:25 ± 5s UTC. 1996-072A did the same to mag 0 at 20:22:17 ± 3s UTC.

I captured both flares/glints on photograph, but in both cases only the very brief glints show up (almost star-like) and not the fainter rest of the trail, hence no useful positions could be derived from the images and they are not even worth posting here.

Thursday, 24 August 2006

20% off on all Weapons of Mass Destruction!!!!

Okay, after Hezbollah visited my website yesterday, they seemed to have given a call to their benefactors to check things out. Because today I found these IP entries in my webstats:



(Click image to enlarge)

Maybe I ought to start including some Google ads for Weapons of Mass Destruction on my webpage, it might perhaps bring me some revenues... :-p

PS: and welcome back, Cuba!

Wednesday, 23 August 2006

Feind hort mit!

Uuhmmm, yeah....: if you suddenly see this kind of IP with this kind of search engine keywords appear in the webstats of your satelite tracking camera webpage, that gives you reasons to think, isn't it?



(click image to enlarge)

Maybe also the opportunity to say hi to the reader from Cuba that frequently visits... (come to think of it: he/she seems to be gone since Fidel is in hospital...)

* starts to scan the skies for black unmarked helicopters... *

Saturday, 12 August 2006

Slow Lacrosse 5 flare (belated post)

Due to circumstances, a quite belated report.

I observed a beautifull pass of Lacrosse 5 (2005-016A, #28646) one week ago, August 6-7. It was very bright, and showed a slow magnitude zero flare at (Aug 06) 23:15:25 ± 10s UTC.

For the part of the pass that I could observe (roughly from 30 deg altitude NW, where I first picked it up, to 40 deg altitude NE where it moved behind the building) it did not do its 'disappearance trick' this time.

I obtained 3 trail photographs during the pass. The positions indicate Lacrosse 5 was approoxmately 0.4 seconds late

A photograph of the very bright trail fading gradually some seconds after the brightness peak (photograph 2 in the series) can be seen here:



(Click on image for larger version)

Thursday, 3 August 2006

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)

Tuesday, 1 August 2006

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.