Showing posts with label Lacrosse 3. Show all posts
Showing posts with label Lacrosse 3. Show all posts

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.

(click images to enlarge)




Note: the times listed in the Iridium flare picture are 10 seconds off from the real time

Sunday, 13 May 2007

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.


(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.

(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.

(click images to enlarge)


Monday, 12 March 2007

Lacrosse 2 running early

Lacrosse 2 (91-017A), the oldest in the Lacrosse (Onyx) SAR-satellite series still in orbit, is running increasingly early. Yesterday evening it already was over 7 seconds early and clearly off-track relative to a 4 day old elset. Is it going down for a de-orbit?

Yesterday evening saw very clear skies. I gathered a nice batch of data: two images (4 positions) on Lacrosse 2 (91-017A), two images (4 positions) on Lacrosse 3 (97-064A), and three images (6 positions) on USA 129 (96-072A). Plus in addition to this, I catched a stray in one of the Lacrosse 3 images, which turned out to be a 22-year-old Russian rocket booster, Kosmos 1689 Rk (85-090B, #16111).

Below is one of the three images I shot of USA 129.

This evening I skipped tracking activities. I am not feeling well and decided to take some rest instead.


(click image to enlarge)

Saturday, 10 March 2007

A Keyhole and two Lacrosses

Another clear evening last night. I managed to catch one KH and two Lacrosses.

The KH was USA 129 (96-072A). It appears as two rather faint trails on two images: the starting point on the first trail is behind the building. I have it running 0.7s early relative to a 2-day-old elset. I obtained 3 positions

Lacrosse 2 (91-017A) was as much as 1.5s early and 0.1 degree off in cross-track relative to a similar aged elset. I obtained 3 positions.

Lacrosse 3 (97-064A) by contrast was pretty much on-time and on-track. It made a nice bright trail. It briefly and modestly flared up to maybe +1.5 at about 19:49:45 UTC, just before shadow entry. I obtained 2 positions.

Thursday, 8 March 2007

Clear skies at last!

After a month of being clouded out, clear skies at last this evening! I targetted two Lacrosse satellites: Lacrosse 2 (91-017A) and Lacrosse 3 (97-064A). An attempt was also made to capture USA 129, but it was too faint for the camera.

Both Lacrosse satellites made a nice pass, reaching about mag. +2.5. Lacrosse 3 (97-064A) was on-time and on-track. Lacrosse 2 (91-17A) however, was some 0.2s late and 0.1 degree off-track. The photograph (see below) shows that it slowly brightened about midway in the exposure. I dare not call it a flare however, as it is rather marginal.

On below image of the Lacrosse 2 trail: Castor and Pollux at left, alpha Auriga at right. The sat moves from bottom to top.

(click image to enlarge)