Sunday, 20 November 2011

NOSS 3-1 A & C no longer a pair, and Lacrosse 3 is missing

On November 14th and 15th, Alan Figer from France first noted that one of the objects of the NOSS 3-1 pair (2001-040 A & C) was missing. Following up on his message, I could confirm this the next evening, using photography and video. Only one object instead of the usual close pair of two was visible:

Above is the video footage that was shot by me. What turns out to be the A-component can be seen crossing Lyra (bright star is Vega. The glow in the lower left corner is from a nearby lamp), but no C component is to be seen in this video segment (nor was it for one minute before and 3 minutes after this segment). Next, Derek Breit missed it as well in a window of 8 minutes centered on the A object pass, and so did Brad Young.

Over the past few days, two possible obervations have been made of the missing C-object, now well away from the A object, by Brad Young and Bill Arnold.

The break-up of the NOSS 3-1 pair probably means it had reached end of mission. It is interesting to see that some of the older NOSS pairs (and one trio) do still  maintain their pair bonding though..

Lacrosse 3 has gone missing - perhaps deorbitted

Another satellite, the 14 year old SAR satellite Lacrosse 3 (1997-064A) has gone missing in a more serious way. It has not been seen since early October. Several observers including me and Pierre Neirinck have done plane searches but so far, it hasn't been recovered. So it has either manoeuvered into a completely different orbit, or has been de-orbitted. If the latter is true, this possible de-orbit comes half a year after the de-orbit of Lacrosse 2 late March 2011. It leaves two remaining Lacrosses  in orbit (Lacrosse 4 and 5).

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