Miracles do happen after all. This evening (9-10 August) was the only evening with an opportunity to spot the Space Shuttle Endeavour STS-118 on its way to the ISS. And I thought it was a lost case. Heavy cloud cover.
The first pass in deep twilight at 20:03 UTC was indeed lost. An unbroken cloud cover, and no hopes for the next and final pass, 21:37 UTC.
But Lo Behold....at 21:15 UTC I noted gaps in the cloud cover. I could see Vega and Arcturus. The situation was very dynamic, with parts of the sky opening and then filling up again in a matter of tens of seconds, the cloud cover moving very fast...but breaking up a little.
At 21:30 I was ready at the courtyard. At 21:34 I spotted the ISS, passing through the zenith very close to Vega. Three minutes to go for the Shuttle, and the zenith was filling up with clouds again.
21:36....I looked west, hoping to see it near Arcturus. Brief glimpse of the latter, but no luck regarding the Shuttle. Clouds occupied the west. Then moved my watch to the zenith. It was breaking open again. I could see Vega.
21:37....YES!!!!!! For maybe 20 seconds I see it, passing a bit south of Vega, fast and about magnitude 0, similar to Vega!
20 seconds and then it was gone in clouds again. Did not even attempt to photograph, it was futile.
But I saw it! :-)
Friday, 10 August 2007
Monday, 6 August 2007
Observing EAS (ISS deb), and checking out a new observing location
Yesterday evening around 21:02 UTC I observed EAS (the Early Ammonia Servicer, 98-067BA, #31928), the refridgerator-sized tank thrown away from the ISS during the July 23th EVA.
I first picked it up, naked eye, when it passed through northern Ophiuchus at about 50 degrees altitude. It was about mag. +4 to +4.5 at that time. It passed in between Altair and the arrow, and then on to Delphinus, where it rapidly grew fainter.
An attempt to observe the VSSA, another piece of debris jettisoned from ISS the 23th, 10 minutes earlier failed.
The observation was done from a new location. During a bycicle tour with my brother last Tuesday, I explored a part of the open polder to the south-east of my home. In recent years a number of bicycle trails have been constructed there, allowing quick and easy access.
I hit upon a spot some 6.5 km from my home, that seemed promising. No street lanterns for 1.5 km around, and full view down to horizon level a full 360 degrees around. Here's a 360 degree strip panorama I took Friday:
The trail visible is a footpath that crosses the bird sanctuary here. The landscape is a typical Dutch flat polder landscape. This part of the polder is 1.7 meter below sea level.
On bicycle, I can reach this location in 25 minutes. Which is reasonable enough.
Yesterday evening I checked it out by night. In fact I had planned to do some serious observing at the location, but upon arrival I discovered to my dismay that I had forgotten to put my DCF77 radio-controlled clock in my backpack. So I had no reliable time source with me. Bummer...
After darkness fell, the sky quality turned out to be reasonable. The urbanized west of my country where I live is notably affected by light pollution, even at the few rare spots of countryside like these left. Yet being some 5 km away from the nearest town is obviously better than being in the midst of a town (as Cospar 4353 is).
Around 21:40 UTC, with the sun at -16 degrees altitude, I did a limiting magnitude count in Draco, in the zenith. The first count resulted in +6.5, the second in +6.6. And that is quite good for this part of the country. I could see the milky way down to 35 degrees altitude in the south-southeast.
Light domes dominate the lower parts of the sky though. Worst (and plainly bad) is the northwest, the combined domes of Leiden and the hellishly illuminated Heineken brewery at 2.5 km distance. Alphen a/d Rijn creates a dome in the northeast, and the combined domes of Zoetermeer and The Hague can be seen in the south (the latter were perhaps more prominent last evening than on a normal night, as there was cirrus in this part of the sky). The east and southeast is nice though, and so seemed west.
The location is certainly good enough to do meteor observations and satellite observations. The light pollution in the northwest perhaps makes it not so ideal a spot for Aurora observation, although the north itself is good.
It is very deserted there at night. The only people who have business there at night are the people belonging to the farms in the area. So a good, quiet spot to observe undisturbed, and relatively safe I think.
In the future I plan to do meteor observing sessions here (with satellites as a by-product); and I plan to use this location to track objects of interest that remain too low in the sky for my usual observing location Cospar 4353. For example, future Shuttle MECO-orbit observations (during this part of its orbit, some 20 minutes after launch, the Shuttle and its already decoupled tank pass at about 24 degrees altitude for me). The new secondary location will probably get the designation Cospar 4354.
I observed the ISS twice that evening: first in deep twilight while biking towards the location, and then around 21:39 UTC when it made a fine zenith pass. The following image shows it in the zenith, near Lyra:
I made six 10.7 second images during that pass, and stitched them together to show the pass from horizon to horizon:
While I was biking towards the location in twilight, and close to it, a hare jumped out of the grass aside the bike-lane and ran in front of me for tens of yards. Going back in darkness, another startled hare threw itself in front of my wheels and I had to brake to avoid disaster.
I first picked it up, naked eye, when it passed through northern Ophiuchus at about 50 degrees altitude. It was about mag. +4 to +4.5 at that time. It passed in between Altair and the arrow, and then on to Delphinus, where it rapidly grew fainter.
An attempt to observe the VSSA, another piece of debris jettisoned from ISS the 23th, 10 minutes earlier failed.
The observation was done from a new location. During a bycicle tour with my brother last Tuesday, I explored a part of the open polder to the south-east of my home. In recent years a number of bicycle trails have been constructed there, allowing quick and easy access.
I hit upon a spot some 6.5 km from my home, that seemed promising. No street lanterns for 1.5 km around, and full view down to horizon level a full 360 degrees around. Here's a 360 degree strip panorama I took Friday:
(click image to enlarge)
The trail visible is a footpath that crosses the bird sanctuary here. The landscape is a typical Dutch flat polder landscape. This part of the polder is 1.7 meter below sea level.
On bicycle, I can reach this location in 25 minutes. Which is reasonable enough.
Yesterday evening I checked it out by night. In fact I had planned to do some serious observing at the location, but upon arrival I discovered to my dismay that I had forgotten to put my DCF77 radio-controlled clock in my backpack. So I had no reliable time source with me. Bummer...
After darkness fell, the sky quality turned out to be reasonable. The urbanized west of my country where I live is notably affected by light pollution, even at the few rare spots of countryside like these left. Yet being some 5 km away from the nearest town is obviously better than being in the midst of a town (as Cospar 4353 is).
Around 21:40 UTC, with the sun at -16 degrees altitude, I did a limiting magnitude count in Draco, in the zenith. The first count resulted in +6.5, the second in +6.6. And that is quite good for this part of the country. I could see the milky way down to 35 degrees altitude in the south-southeast.
Light domes dominate the lower parts of the sky though. Worst (and plainly bad) is the northwest, the combined domes of Leiden and the hellishly illuminated Heineken brewery at 2.5 km distance. Alphen a/d Rijn creates a dome in the northeast, and the combined domes of Zoetermeer and The Hague can be seen in the south (the latter were perhaps more prominent last evening than on a normal night, as there was cirrus in this part of the sky). The east and southeast is nice though, and so seemed west.
The location is certainly good enough to do meteor observations and satellite observations. The light pollution in the northwest perhaps makes it not so ideal a spot for Aurora observation, although the north itself is good.
It is very deserted there at night. The only people who have business there at night are the people belonging to the farms in the area. So a good, quiet spot to observe undisturbed, and relatively safe I think.
In the future I plan to do meteor observing sessions here (with satellites as a by-product); and I plan to use this location to track objects of interest that remain too low in the sky for my usual observing location Cospar 4353. For example, future Shuttle MECO-orbit observations (during this part of its orbit, some 20 minutes after launch, the Shuttle and its already decoupled tank pass at about 24 degrees altitude for me). The new secondary location will probably get the designation Cospar 4354.
I observed the ISS twice that evening: first in deep twilight while biking towards the location, and then around 21:39 UTC when it made a fine zenith pass. The following image shows it in the zenith, near Lyra:
(click image to enlarge)
I made six 10.7 second images during that pass, and stitched them together to show the pass from horizon to horizon:
(click image to enlarge: 4000 pixel wide image!)
While I was biking towards the location in twilight, and close to it, a hare jumped out of the grass aside the bike-lane and ran in front of me for tens of yards. Going back in darkness, another startled hare threw itself in front of my wheels and I had to brake to avoid disaster.
Sunday, 5 August 2007
Another -8 Iridium flare
Bright Iridium flares never are a bore, and the summer season with its long twilight at my latitude has plenty of them.
Last night at 22:56:24 UTC (Aug 4) I observed Iridium 21 (99-032B) flare brilliantly to mag. -8 in Ophiuchus. Like 31 July's Iridium 74 flare (which occurred in roughly the same sky position), it visually had a yellowish colour.
It was a beautifully clear, warm night. In addition to Iridium 21, I also observed a nice bright pass of ISS, reaching mag. -3. Another object that never bores. On the classified front, I observed IGS 1B (03-009B) and the NOSS 3-4 Centaur rocket (07-027B) again.
While imaging IGS 1B, certain noises through an open window nearby reminded me that on a beautiful night like this, some other people also engage in their own particular pleasurable hobbies too... ;-)
As I was very tired, I stopped after observing and photographing the Iridium flare.
Last night at 22:56:24 UTC (Aug 4) I observed Iridium 21 (99-032B) flare brilliantly to mag. -8 in Ophiuchus. Like 31 July's Iridium 74 flare (which occurred in roughly the same sky position), it visually had a yellowish colour.
(click image to enlarge)
It was a beautifully clear, warm night. In addition to Iridium 21, I also observed a nice bright pass of ISS, reaching mag. -3. Another object that never bores. On the classified front, I observed IGS 1B (03-009B) and the NOSS 3-4 Centaur rocket (07-027B) again.
While imaging IGS 1B, certain noises through an open window nearby reminded me that on a beautiful night like this, some other people also engage in their own particular pleasurable hobbies too... ;-)
As I was very tired, I stopped after observing and photographing the Iridium flare.
Saturday, 4 August 2007
NOSS 3-4 Centaur rocket brightness variation
Last night (3-4 August) I observed the NOSS 3-4 Centaur rocket stage (07-027B) again over a large part of its trajectory. I obtained a number of images (yielding 10 positions), and they nicely show the varying brightness of the rocket stage due to its tumbling. It can be well seen in below series of snapshots, which were taken at approximately 1 minute intervals:
note added 05/08: the variation is not in each sub-image, but between the images. Basically, the sequence for these four is: picture #1 bright trail; picture #2 faint trail; picture #3 bright trail again; picture #4 faint trail again.
Apart from 07-027B, I also observed IGS 1B (03-009B) and a mag. -0.5 flare of Iridium 74 (98-032D). Around the time of the Iridium flare however, cirrus clouds moved in and I stopped observing.
(click image to enlarge)
note added 05/08: the variation is not in each sub-image, but between the images. Basically, the sequence for these four is: picture #1 bright trail; picture #2 faint trail; picture #3 bright trail again; picture #4 faint trail again.
Apart from 07-027B, I also observed IGS 1B (03-009B) and a mag. -0.5 flare of Iridium 74 (98-032D). Around the time of the Iridium flare however, cirrus clouds moved in and I stopped observing.
Wednesday, 1 August 2007
The NOSS 3-4 centaur rocket (07-027B): a nice new object
June 15 2007 saw the launch of NRO's NOSS 3-4 satellites. They belong to the new US Navy twin satellite constellation (the old NOSS-es were trio's) the purpose of which is to pinpoint the origin of shipping communications.
The payload couple (07-027A & C) and the last stage NOSS 3-4r Centaur rocket (07-027B) are now being tracked by amateurs. For me, the Centaur stage (07-027B) is the most interesting, as it is bright. It is also slow moving. And making zenith-passes near midnight for my station at the moment. Which all makes it a fine photographic target.
The object slowly tumbles, as is apparent from a very slow variation in magnitude. Over the course of a minute or so, it varies between mag. +4 and +1.5 on a zenith pass.
Last week I observed the object for the first time, on 3 different nights including last night (I observed a fine list of other objects from my regular observing program as well on these nights).
On the first two nights I was greatly hampered by drifting fields of cumuli but could nevertheless capture the object through gaps in the cloud cover. Last night was clear and I could follow it along a large part of its trajectory, the slow amplitude in brightness due to the tumbling being very apparent. Below three images show the object as captured on the nights of July 29-30, 30-31 and July 31-Aug 1.
Last night the first (out of 3) image of the object suffered from an attempted counter-intelligence attack though ;-)
Frenkie, the cat of my neighbour, joined me at the courtyard that night and started to hug me and my camera tripod in the way cats do. As a result the first image I obtained contained a wobbled satellite trail and I did not measure it. I chased away Frenkie, as lovely as he is, and shot two more images one of which is shown above.
(Frenkie is now suspected to be back at his CIA headquarters, reporting to his commander, who carefully trained him: "Meooow, mission only partly accomplished").
I also had an Iridium flare path center coming almost exactly over my house last night. It concerned Iridium 67 (98-021F) and it flared brilliantly to at least mag. -8. The flare had a distinct yellow colour.
The previous night also saw a nice (less bright: mag -1) flare of Iridium 64 (98-021C):
The payload couple (07-027A & C) and the last stage NOSS 3-4r Centaur rocket (07-027B) are now being tracked by amateurs. For me, the Centaur stage (07-027B) is the most interesting, as it is bright. It is also slow moving. And making zenith-passes near midnight for my station at the moment. Which all makes it a fine photographic target.
The object slowly tumbles, as is apparent from a very slow variation in magnitude. Over the course of a minute or so, it varies between mag. +4 and +1.5 on a zenith pass.
Last week I observed the object for the first time, on 3 different nights including last night (I observed a fine list of other objects from my regular observing program as well on these nights).
On the first two nights I was greatly hampered by drifting fields of cumuli but could nevertheless capture the object through gaps in the cloud cover. Last night was clear and I could follow it along a large part of its trajectory, the slow amplitude in brightness due to the tumbling being very apparent. Below three images show the object as captured on the nights of July 29-30, 30-31 and July 31-Aug 1.
(click images to enlarge)
Last night the first (out of 3) image of the object suffered from an attempted counter-intelligence attack though ;-)
Frenkie, the cat of my neighbour, joined me at the courtyard that night and started to hug me and my camera tripod in the way cats do. As a result the first image I obtained contained a wobbled satellite trail and I did not measure it. I chased away Frenkie, as lovely as he is, and shot two more images one of which is shown above.
(Frenkie is now suspected to be back at his CIA headquarters, reporting to his commander, who carefully trained him: "Meooow, mission only partly accomplished").
I also had an Iridium flare path center coming almost exactly over my house last night. It concerned Iridium 67 (98-021F) and it flared brilliantly to at least mag. -8. The flare had a distinct yellow colour.
(click image to enlarge)
The previous night also saw a nice (less bright: mag -1) flare of Iridium 64 (98-021C):
(click image to enlarge)
Monday, 23 July 2007
Another fine night, USA 193 bright & a Lacrosse 3 flare
Friday evening and Sunday evening saw two other observing opportunities. On Friday it remained restricted to Lacrosse 3 & the Lacrosse 5 rk (97-064A & 05-016B), as clouds came in at a certain point (this made me miss a predicted -8 Iridium flare alas). I saw Lacrosse 3 (97-064A) flare to mag +0.5 however at 23:30:44 UTC (Jul 20).
Sunday night was very fine however, and I catched Lacrosse 3 & 4, plus IGS 4A/R2 (07-005A) and USA 193 (06-057A). The latter was quite bright (+0.5) while passing in the northwest. The second of the two images below shows it as it is just disappearing out of sight behind the roof. The other image shows IGS 4A/R2.
USA 193 was 2.3s early relative to Ted's elset 07202.04020244.
Note: the time indicated in above image is in error, apologies.
Sunday night was very fine however, and I catched Lacrosse 3 & 4, plus IGS 4A/R2 (07-005A) and USA 193 (06-057A). The latter was quite bright (+0.5) while passing in the northwest. The second of the two images below shows it as it is just disappearing out of sight behind the roof. The other image shows IGS 4A/R2.
USA 193 was 2.3s early relative to Ted's elset 07202.04020244.
(click images to enlarge)
Note: the time indicated in above image is in error, apologies.
Thursday, 19 July 2007
Observing again
Last night was very clear, and I finally could get myself to observe again after a 2-month period of inactivity (see previous post).
In 3 hours observing time I catched a nice batch of objects: USA 193 (06-057A), IGS 4A/R2 (07-005A), Lacrosse 3 (97-064A), Lacrosse 4 (00-047A), the Lacrosse 5 rk (05-016B) and a nice -2 flare of Iridium 14 (99-032A). I also visually observed IGS 1B (03-009B) but the trail ends on the image were to marginal to measure.
Below pictures showing:
- the Japase radar reco satellite IGS 4A/R2 and the American radar reco satellitre Lacrosse 3 in one and the same image, in Cassiopeia;
- the flare of Iridium 14.
Note: the times listed in the Iridium flare picture are 10 seconds off from the real time
In 3 hours observing time I catched a nice batch of objects: USA 193 (06-057A), IGS 4A/R2 (07-005A), Lacrosse 3 (97-064A), Lacrosse 4 (00-047A), the Lacrosse 5 rk (05-016B) and a nice -2 flare of Iridium 14 (99-032A). I also visually observed IGS 1B (03-009B) but the trail ends on the image were to marginal to measure.
Below pictures showing:
- the Japase radar reco satellite IGS 4A/R2 and the American radar reco satellitre Lacrosse 3 in one and the same image, in Cassiopeia;
- the flare of Iridium 14.
(click images to enlarge)
Note: the times listed in the Iridium flare picture are 10 seconds off from the real time
Thursday, 12 July 2007
Inoperative period
Just a note that SatTrackCam/Cospar 4353 due to circumstances has been inoperative for a while, and might continue to be so for a while. Apart from the very bad weather we are experiencing the past weeks, a reason for this is in a tragic personal loss affecting my life currently.
Sunday, 20 May 2007
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.
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.
(click images to enlarge)
Sunday, 13 May 2007
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).
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.
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.
(click image to enlarge)
Thursday, 3 May 2007
Lacrosse 3
Phil Masding provided me with a number of potential flare time predictions for Lacrosse 3 (97-064A). The aim is to determine at what angle flares will be no longer visible.
Two of these predictions were for yesterday evening and as the sky was very clear again, I covered both.
At 21:30:38 UTC (2 seconds after the nominal prediction) and almost right in the zenith for me, Lacrosse 3 indeed "flared", albeit very modestly. The short increase in brightness was no more than say 0.5 magnitudes but discernable. Below is the image (visually, the "flare" was somewhat better discernable).
On the other hand, during the second predicted time (23:12:38) Lacrosse 3 did nothing, it was steady as usual.
Two of these predictions were for yesterday evening and as the sky was very clear again, I covered both.
At 21:30:38 UTC (2 seconds after the nominal prediction) and almost right in the zenith for me, Lacrosse 3 indeed "flared", albeit very modestly. The short increase in brightness was no more than say 0.5 magnitudes but discernable. Below is the image (visually, the "flare" was somewhat better discernable).
On the other hand, during the second predicted time (23:12:38) Lacrosse 3 did nothing, it was steady as usual.
(click image to enlarge)
Wednesday, 2 May 2007
First observation of one of the new IGS objects
I managed to observe one of the new Japanese IGS eastern plane objects for the first time this night (see image below). It concerned the rocket-booster, 07-005C (#30588), which amateur trackers name either IGS 4r or IGS R2r.
It made a zenith pass and was bright and easy, mag. +1.5 in the zenith and about +2 when passing close to Polaris. It was steady, no sign of tumbling.
It made a zenith pass and was bright and easy, mag. +1.5 in the zenith and about +2 when passing close to Polaris. It was steady, no sign of tumbling.
(click image to enlarge)
Tuesday, 1 May 2007
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.
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)
Iridium flare season
It was very transparent last night, to the extend that the full moon didn't seem to hamper much. Alas I had not much opportunity to observe, as I was franticly making the last final edits to a research proposal, the dead-line of which was this afternoon.
I did catch this fine mag. -6 flare of Iridium 25 at 51 degree elevation in the east though (see image below). The season of many bright Iridium flares high in the sky has started again
Main focus at the moment is still on gathering material to calibrate the times of my camera. Currently a recalibration of -0.30 s (as opposed to the -0.35s I initially took) seems to get times in line.
Interestingly, this -0.30s means the time calibration value is similar again to that which I initially obtained way back in August 2005. It then jumped by 0.3s after I made a change in my camera settings in September 2005. Apparently now it is back at the old value again. I did not consciously make another change in my camera settings, but have accessed the camera recently with Canon software to test that software, and apparently it did change settings.
I did catch this fine mag. -6 flare of Iridium 25 at 51 degree elevation in the east though (see image below). The season of many bright Iridium flares high in the sky has started again
Main focus at the moment is still on gathering material to calibrate the times of my camera. Currently a recalibration of -0.30 s (as opposed to the -0.35s I initially took) seems to get times in line.
Interestingly, this -0.30s means the time calibration value is similar again to that which I initially obtained way back in August 2005. It then jumped by 0.3s after I made a change in my camera settings in September 2005. Apparently now it is back at the old value again. I did not consciously make another change in my camera settings, but have accessed the camera recently with Canon software to test that software, and apparently it did change settings.
(click image to enlarge)
Sunday, 29 April 2007
USA 116 flaring
Pierre recovered USA 116 (95-066A) on the 24th. I observed it this morning, making a nice pass high west.
It was bright for much of its track, +2 to +1, and slowly flared to +0.5 at 02:05:45 UTC (29 April) on the Bootes-Corona Borealis border. An image of this flare is below.
Five minutes earlier I observed a nice flare of Iridium 61 (predicted -8 but I think it was a bit fainter), see also below (2nd image).
It was bright for much of its track, +2 to +1, and slowly flared to +0.5 at 02:05:45 UTC (29 April) on the Bootes-Corona Borealis border. An image of this flare is below.
Five minutes earlier I observed a nice flare of Iridium 61 (predicted -8 but I think it was a bit fainter), see also below (2nd image).
(click images to enlarge)
Thursday, 26 April 2007
Another METOP-A flare, hazy skies and timings again
The skies have turned hazy since yesterday. With the moon and the urban environment, this means serious tracking is very difficult.
I observed another flare of METOP-A (06-044A) yesterday (25 Apr) at 20:08:42 UTC. I watched this pass because the track and time were very close to that of the flare observation of the 20th.
Indeed, it flared at virtually the same spot, in the tail of the Big Dipper. Due to the conditions the brightness was difficult to estimate: certainly mag. 0, possibly -1. With the naked eye I could barely make out the dipper stars itself, but the flare was easily visible.
There are still some strange things going on with my timings. I have chosen to target as many non-classifieds as possible to get some insight into the timing consistency.
I observed another flare of METOP-A (06-044A) yesterday (25 Apr) at 20:08:42 UTC. I watched this pass because the track and time were very close to that of the flare observation of the 20th.
Indeed, it flared at virtually the same spot, in the tail of the Big Dipper. Due to the conditions the brightness was difficult to estimate: certainly mag. 0, possibly -1. With the naked eye I could barely make out the dipper stars itself, but the flare was easily visible.
There are still some strange things going on with my timings. I have chosen to target as many non-classifieds as possible to get some insight into the timing consistency.
Sunday, 22 April 2007
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....
- 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....
(click images to enlarge)
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:
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:
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:
ISS made a nice pass close to Procyon in deep twilight. The wisps of cirrus still present at that time would rapidly dissolve:
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:
(click image to enlarge)
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:
(click image to enlarge)
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:
(click images to enlarge)
ISS made a nice pass close to Procyon in deep twilight. The wisps of cirrus still present at that time would rapidly dissolve:
(click image to enlarge)
Saturday, 21 April 2007
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).
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)
Subscribe to:
Posts (Atom)