Sunday, 19 July 2009

USA 186 and IGS 1B

Friday evening saw very clear skies during twilight. Unfortunately, it got clouded soon after. This meant I was prevented from targetting a nice pass of the STSS-ATRR rocket (09-023B) and USA 161 (01-044A). I did image the Keyhole USA 186 (05-042A) however, in deep twilight, obtaining three positions. This object recently (July 15) made a small manoeuvre.

Yesterday was a repeat of the day before: clear at the start of the evening, but clouded out after midnight. Again I missed out on USA 161 and the STSS-ATRR rocket. I did manage to catch the defunct Japanese radar spy IGS 1B (03-009B), obtaining six positions. It was bright while ascending through Ophiuchus in the south, then faded somewhat, became quite bright again while crossing Draco and then faded quickly beyond visibility. Visually, at moments the object was slightly and quickly fluctuating in brightness in irregular fashion. Some of that fluctuation can be seen in the right-hand part of the brightness diagram below, derived from one of the images (top).

(click images to enlarge)

No comments: