[meteorite-list] OSIRIS Spots Philae Drifting Across Comet

[Ron Baalke]

http://blogs.esa.int/rosetta/2014/11/17/osiris-spots-philae-drifting-across-the-comet/

OSIRIS spots Philae drifting across the comet
European Space Agency
November 17, 2014

[Images] 			
These incredible images show the breathtaking journey of Rosetta's Philae 
lander as it approached and then rebounded from its first touchdown on 
Comet 67P/Churyumov-Gerasimenko on 12 November 2014.
Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

The mosaic comprises a series of images captured by Rosetta's OSIRIS camera 
over a 30 minute period spanning the first touchdown. The time of each 
of image is marked on the corresponding insets and is in GMT. A  comparison 
of the touchdown area shortly before and after first contact with the 
surface is also provided.

The images were taken with Rosetta's OSIRIS narrow-angle camera when the 
spacecraft was 17.5 km from the comet centre, or roughly 15.5 km from 
the surface. They have a resolution of 28 cm/pixel and the enlarged  insets 
are 17 x 17 m.

>From left to right, the images show Philae descending towards and across 
the comet before touchdown. The image taken after touchdown, at 15:43 
GMT, confirms that the lander was moving east, as first suggested by the 
data returned by the CONSERT experiment, and at a speed of about 0.5 m/s.

The final location of Philae is still not known, but after touching down 
and bouncing again at 17:25 GMT, it reached there at 17:32 GMT. The imaging 
team is confident that combining the CONSERT ranging data with OSIRIS 
and navcam images from the orbiter and images from near the surface and 
on it from Philae's ROLIS and CIVA cameras will soon reveal the lander's 
whereabouts.

[Ed's note - added for clarification: Touchdown occurred at 15:34 GMT 
spacecraft time (with the signal received on Earth at 16:03 GMT); the 
image marked 'touchdown' in the graphic above was taken after touchdown, 
at 15:43 GMT, but clearly shows the evidence of the touchdown event when 
comparing with an image taken previously]

The insets are provided separately below (the timestamps are recorded 
in the filenames).
All images credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA