Monday, 16 April 2007

Flares of Iridium 14, ISS (!), USA 186 and Lacrosse 4

This evening (the 16th) and the evening of the 14th I observed two nice flares of the same Iridium satellite, Iridium 14 (99-032A). On the 14th it flared to mag. -5, and this evening to -6 (top foto), in twilight. Less than a minute earlier Iridium 70 flared at virtually the same position, but less brightly.

(click images to enlarge)

The International Space Station (ISS) made a number of fine bright passes as well the past days. below are two images of April 14 and 15, including a fine mag. -3.5 twilight pass (top image).

(click images to enlarge)

My new neighbours were on the courtyard enjoying the mid-summer like temperatures (+28 C daytime this weekend, very unusual for mid-April) when I was targetting the twilight pass on the 15th. Seeing me put up my tripod, they asked me what I was doing. I explained, and then pointed out the rising ISS to them. At first they didn't believe me, thinking it was an aircraft, but then they realized I had predicted it to appear, so I probably was right. Still, I could see a look in their face that probably meant something like: "A nutter, but not a dangerous one...".

ISS did something unusual during the 2nd evening pass on the 15th. It was low in the west crossing into Gemini at mag. -2 or so, when suddenly (as if a switch was turned) it flared up by at least 1.5 to 2 extra magnitudes, for maybe a second or 2-3, and then back to its previous brightness again. Very conspicuous. I also had the impression of an orange colour but that could be due to the low elevation. Never seen this before with ISS. Time was approximately 21:07:15 UTC (Apr 15).

Lacrosse 4 (00-047A) flared as well that evening, briefly to mag. +0.5. This was either at 23:09:53 or 23:10:03 UTC (there is some confuson with me about the correct time).

05-042A (USA 186) shortly flared to mag. 0 at 19:45:58 UTC on Apr 15. I catched this flare on photograph but it is so short it is almost stellar. I saw it flare again on the 16th at 20:08:27, to mag. -1 and again very short (maybe a second duration).

Strangely enough I again failed to spot IGS 1B (03-009B), the Japanese radar satellite that recently had a power failure, on the 15th. This although this was a zenith pass, with the sat emerging out of eclipse in the zenith. But I could see no trace of it visually and on the photographs. This while previously this satellite would easily be visible, attaining magnitude +1.5 to +2 during high passes.

Especially the 15th resulted in a nice batch of positions on various objects.

No comments: