Friday, 23 March 2007

A Lacrosse 5 Disappearance and Re-appearance

Yesterday evening at about 20:20 UTC I saw Lacrosse 5 (05-016A) do its "disappearance trick" again: this time however followed by a re-appearance about half a minute later.

Disappearance - I observed it being very bright (mag. 0) while ascending in the sky. Just when I was aiming my camera and about to trigger it, it disappeared in a few seconds time. Completely out of naked-eye range. This was at about 20:19:30 UTC, but this time can be somewhat off for reasons stated below.

Re-appearance - At 20:19:50 ± 5 seconds UTC (I am more certain of this time) it re-appeared again in a few seconds time, close to Capella, attaining a brightness of magnitude +1. From that moment on it was steady, gradually fading to mag. +2, crossing the Big Dipper and Draco untill I lost it behind the building.

The photograph below was taken within half a minute of it re-appearing again and shows that it was very bright again.

The observation was a bit chaotic because my neighbour started a chat with me and I was explaining my observations to her when Lacrosse 5 disappeared (hence why the time of that event did not entirely stuck in my memory). Moreover her cat tried to hug my tripod, so I gently had to scoop the animal away.

I also catched USA 129 (96-072A) and USA 186 (05-042A) last evening, but the trails were very faint and I could not get unambiguous positions from them.

I also have a late report to make on the evening of March 14th, when I gathered a total of 6 positions on Lacrosses 2 & 3.

(click image to enlarge)

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