Sunday 12 December 2010

Recovering SDS 3-3 (USA 179) and following the UNKNOWN 101208 geosat

Our amateur network had lost track recently of the HEO satellite SDS 3-3 (USA 179, 2004-034A), so it had to be recovered. Radio doppler shift data by an amateur remaining anonymous provided enough information to Ted Molczan to issue a search orbit for visual or camera recovery.

Last evening started clear, and I quickly recovered it very close to Ted's predicted search orbit position. It was about 0.3 degrees off from the latter, so a very neat result! See the image below, the first in a series I shot yesterday with the Carl Zeiss Jena Sonnar MC 2.8/180mm:

click image to enlarge

After imaging another HEO too, the ELINT USA 184 (2006-027A), clouds came in. The situation turned very dynamic, with the sky going from clear to clouded to clear in a matter of minutes.

I wanted to see if I could image the 'mystery geostationary satellite' which I discovered on 8 December again, a satellite that has now been temporarily designated as Unknown 101208. With my initial December 8 observations and Greg Robert's December 9 & 10 observations, Mike could fit a reasonably good orbit:
Unknown 101208
1 99991U 10344.69054052 0.00000000 00000-0 00000-0 0 03
2 99991 0.0670 10.3484 0003000 147.2004 212.7996 1.00405600 05

The object is drifting eastward at a rate of about 0.5 degrees/day and is now well east of the Turksat 2A & 3A duo (it was west of them when I discovered it on the 8th). It's identity still remains a mystery. Early ideas about it being a DSCS relocating, can now be dismissed.

Under very dynamic conditions, I managed to take advantage of a clearing that lasted literally only minutes (!) to capture it again last evening, along with a few others in the same image. The latter objects were the Milstar 6 r/b (2003-012B) and Mentor 4 (USA 202, 2009-001A), and in addition the non-classified geostationaries Turksat 2A & 3A, Thuraya 2 and Express AM-1.

While the image quality was bad (quite fogged images), the object clearly showed up. Below is one of the images, showing the mystery satellite with the Turksat duo. Compare to the December 8th picture here, when the mystery satellite was still west of the Turksats:

click image to enlarge

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