Sunday, 25 June 2006

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.

Wednesday, 21 June 2006

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.

Sunday, 18 June 2006

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).

Sunday, 11 June 2006

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

sum 0.05354