Another GOCE flare

Yesterday evening started very clear, but ended cloudy. Nevertheless I was able to bag several objects: the Lacrosses 2 & 3, the NOSS 3-4 Centaur rocket, GOCE flaring, and the HEO objects USA 179 and USA 184.

GOCE (the European Gravity field and steady state Ocean Circulation Explorer) made a zenith pass, zipping close to M31 at mag. +4 to +5 and then flaring briefly to mag. +2 at 17:24:23.15 UTC. It was nice to watch. GOCE is in a very low orbit and moves very fast: the flare almost looks like a meteor to the eye.

The flare was caused by the 67.5 degree panel and the time yields a flare angle of 93.6 degree and tilt of 51.9 degree. The 93 degree angle is consistent for all GOCE flares I so far observed (theoretically, that angle should be 90 degrees, i.e. at the moment of culmination when the sun-observer-satellite flight direction makes a square angle). The miss distance to the theoretical central flare path (quite large in this instance: some 175 km!) doesn't really seem to matter with regard to the flare brightness: they always come out at +2 to +3 (even when, as in this case, the tilt is off from 67.5 degree by over 15 degrees).

Below is the image, the derived brightness profile (edit - please note that the time stated in the upper left corner of the diagram is wrong: I inadvertently mentioned the end of the exposure here instead of the flare peak time), and the observing geometry. Note how the flare peak is slightly asymmetrical, the descending branch is slightly steeper.

click images to enlarge

Off to a good start: a GOCE and a Lacrosse 2 flare

2010 started off well with a very clear evening of January 1st. I observed GOCE (09-013A), the Lacrosses 2 & 3 (91-017A & 97-064A), the tumbling NOSS 3-4 Centaur rocket (07-027B), and the HEO objects USA 179, 184 and 200.

I was treated to two small flares: one by GOCE (09-013A) and one by Lacrosse 2 (91-017A).

The GOCE flare was a mild one to about +3, at 17:32:58.0 UTC. It was caused by the 67.5 degree panel. The time of the flare (accurate to 0.1s) yields an angle of 93.2 and tilt of 66.3 with a nominal mis distance to the theoretical flare path (angle 90 degrees, tilt 67.5 degrees) of 19.4 km at the time of observation (and closest approach to 17.1 km 1.2 seconds earlier at 17:32:56.8 UTC).

So far, all the GOCE mild flares I observed were with an angle ~93 degrees. The distance to the nominal flare path of this one was much less than for the three flares previously observed by me, but that doesn't seem to have much influence on the observed flare brightness: they were all around +3 magnitude.

Below are the picture, the derived brightness profile, and a depiction of the flare path geometry based on Simone Corbellini's Visual Sat-Flare Tracker 3D software.

click images to enlarge

Unexpectedly, I also captured a brief (<0.5s) flare/glint by Lacrosse 2 (91-017A) at 17:56:58.4 UTC. Below is the image and the resulting brightness profile:

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Last observations of the year, and 2009 at a glance

December 2009 saw a lot of clouded sky, a few clear frosty skies, and lots of snow (for our country at least). After my December 6th observations (see previous post) I observed on December 13th (under modest conditions) and December 28th (under good conditions).

Targets imaged were the HEO objects USA 179 (04-034A), USA 184 (06-027A) and USA 198 (07-060A), and the STSS Demo objects (09-052A & B); and the LEO objects Lacrosse 2 (91-017A) and Lacrosse 5 (05-016A).

These are probably my last observations for this year, as today is overcast and tonight will see fireworks. So, what did 2009 bring on the observational front?

2009 was a good year. I observed on 77 nights, obtaining a total of 953 positions (8 visually, 945 photographically). They were spread over the year as follows:





These observations concern 32 different classified objects (both payloads and rocket boosters), plus a number of special-interest non-classified objects such as Space Shuttles, GOCE, and the Iridium 33 wreckage:

click image to enlarge list

Just for fun, I have also plotted all obtained positions on an RA/Declination map:

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The clustering in certain positions is because I tend to select sky areas with easily recognizable bright star patterns. This helps easy aiming of the camrea, and it also speedens initial star identifications during the astrometric reduction of the images.

An unidentified HEO object

Yesterday evening was very clear. I photographed the STSS Demo r/b (09-052C) using the EF 50/2.5 Macro, and then switched to the EF 100/2.8 Macro USM to capture the HEO objects USA 184 (06-027A) and USA 198 (07-060A).

One of the four images capturing the latter, contained an unknown object some 3 degrees south of USA 198. It is a clear trail, similar to that of USA 198 in length and direction. It shows evidence of being the capture of a brief flare. And it doesn't match any known object from the unclassified or classified catalogues.

Below is a detail of the image showing the object (the inset is a 200% blow-up). The trail is about 20 pixels long, or about 3.5'.

click image to enlarge

USA 179 and 184

After a month-long absence due to amongst other a hollidays in Canada, I was able to do some observations again last Saturday evening. It was very clear (and rather cold).

Due to a social activity earlier in the evening I had missed the LEO window (which is very short this time of the year at 52 degrees latitude), so I popped the EF 100/2.8 Macro USM on the camera and targetted two Molniya objects high in the sky: USA 179 (2004-034A) and USA 184 (06-027A). The first is an SDS-3 communications satellite, the second an advanced Trumpet SIGINT and SBIRS platform.

Both objects showed up brightly on the images, USA 184 nearly stellar and USA 179 creating clear short trails. Here's a part of one of the USA 179 (2004-034A) images, a small field in Cassiopeia:

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I obtained the launch patches of these two objects recently.

USA 179:



USA 184:

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 HTV-1 and Molniya satellites

Yesterday evening 13-14 September was clear again. I had a very fine near-zenith pass of the HTV-1 (09-048A) on it's way to the ISS. It was fast and bright again (mag. 0), and again distinctly orange. It flared to -2 at 19:28:35 UTC (13 Sep). On below image (taken with the Tamron lens this time, at 17 mm) it is rising over the rooftops, with the distinct orange colour visible:

click image to enlarge

I also imaged the high altitude objects USA 184 (06-027A) and USA 198 (07-060A) again later that night, using the EF 100/2.8 Macro USM lens. Below animated GIF is composed of 5 images of 10 seconds exposure, taken at 20 second intervals, and shows USA 198 between 22:04:02 and 22:05:22 UTC. It was cruising at 34300 km altitude at that time, over 56.8N, 11.9 E. The frames are crops of small parts of the original images, shown here at full pixel resolution. One pixel equals 10" (arcseconds):

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

A Keyhole flaring, a Molniya ELINT and the USA 144 decoy again

The evenings of August 31 and September 1 were clear. On August 31 I targetted two higher objects with the EF 100/2.8 Macro USM: USA 184 (06-027A), an ELINT in a Molniya orbit (see a few posts back), and the USA 144 Decoy again (99-028C). On September 1st, two LEO objects were the target: the KH-12 Keyholes USA 129 (96-072A) and USA 186 (05-042A).

USA 129 brightly flared to mag. -1 at 20:34:11.1 UTC (Sep 1st). The camera was open when it did:

Click image to enlarge

The series of images of the USA 144 Decoy yielded information again about the periodicity of it's brightness (indicating the tumbling period). Like the data of August 25 and 27, it fits a sinusoid with a period of 71 second.

Click diagram to enlarge

A keyhole, a Trumpet, IGS 1B, and strays

Yesterday evening it was clear again. I captured the KH-12 Keyhole USA 186 (05-042A), and also IGS 1B (03-009B). In addition, two strays were captured, and the EF 100/2.8 Macro USM was used to capture the Trumpet ELINT USA 184 (06-027A) again.

In one of the pictures with USA 186, a piece of Delta 1 debris, 75-027E, was captured as a bright stray. In one of the images with IGS 1B, the Kosmos 1975 rocket (88-093B) was captured as a bright stray. Below is the latter image showing a part of Northern Cygnus:

Click image to enlarge

USA 184 Trumpet (?) ELINT and more

Yesterday in the daytime, it was clouded and rainy. It cleared marvelously in the evning though. I detected the clearings too late to capture the evening Keyhole passes, but captured a number of other objects: IGS 1B (03-009B, a defunct Japanese SAR), Lacrosse 2 (91-017A, a SAR as well), the NOSS 3-3 Duo (05-004 A & B), and two HEO objects: USA 184 (06-027A) and the USA 144 decoy (99-028C) again.

The image below shows the USA 144 decoy again, and is a somewhat better picture than that which I posted in a previous post:

Click image to enlarge

USA 184 was imaged as well, and for the first time by me. It showed up bright. It is probably a Trumpet-class ELINT satellite. It is in a Molniya orbit (see below) and at the time of imaging was at an altitude of 28560 km, over Northern Europe.

Click image to enlarge

Below is one of the images, plus an animated GIF of all five images, showing the movement perpendicular to the night sky rotation:

Click images to enlarge