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Nanosail-D Image 2011/05/24(UT)

Ralf Vandebergh
R.Vandebergh

Ralf Vandebergh(250mm Newton)
Nanosail-D2 May 24 image sequence
Nanosail-D is the first experimental solar sail in orbit.
Result from a great Nanosail-D imaging session on May 24, were it reached an altitude of 62 degrees and it was wildly flashing for the naked eye. Because the seeing was good, many frames were sharp so it was worthy to show a part of the image sequence during closest approach (only the very best frames) in a movie.
This is the evidence that the Sail is resolved and confirmation for my earlier images;
You clearly see the Sail approaching when it visible from an angle and looks elongated, then near closest distance you look clearly straight onto the surface of the Sail. Note also the attitude of the Sail which is in the frames the same.




Nanosail-D2 frames average image version
I have been experimenting with combining single frames of the May 24 Nanosail-D imaging session.
This is a result of a sum of 8 best frames within a sufficient short time-span to not introduce differences
by the changing viewing angle. Time between the single frames is 0.04 sec.
Averaging and shapening is generally done in planetary imaging to increase signal-to-noise ratio
but works limited with satellite captures as you have not many frames.
The result is interesting but it not really show anything new compared with the earlier single-frame
processings. However, I think this is a nicer picture.


Movie of Nanosail-D, (first experimental solar sail in space) made using
frames taken 9 seconds apart. Only the very sharpest frames are used, less
is more. The result looks remarkable ; this must be the first movie showing
the Sail actually tumbling in space. Note that one rotation visible in the
movie might actually be a compression of several rotations which could not
be individually recorded due to lost frames, inevitable connected to the manually
tracking method used with the very high imaging scale.
Note the irregularity of illumination of certain parts of the Sail which
could cause the sub-flashes observed by visual observers. To demonstrate how
part of the pass, presented in the movie would look like for the naked-eye,
I have artificially lowered the resolution to spot-size, comparable with
naked-eye view in the second smaller animation, containing the same frames;
we see indeed flashing.



[バンディバ:オランダ]
[Ralf Vandebergh:Neighbourhood of Maastricht Netherlands]
ALPO-Japan Latest Oplanets Section
2011/06/14
 [ISS] 
2011/05/22
 [Nanosail-D]