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Posted by: Phil Stooke Feb 21 2006, 03:59 AM

These are two images of Comet Borrelly from Deep Space 1. I've been searching for the best images for mapping the nucleus.

I was disturbed to find that the raw images, in fact all the Borrelly data, were never properly archived and are difficult to track down. It seems the Deep Space 1 team were not very interested in collaborating with the PDS on archiving.

Anyway, these are specially processed composites of the versions I've been able to find. They show more detail along the terminator (bottom) than most images I have seen elsewhere. I have been working on a 3D shape model in my spare time. PDS has two shape models which are not suitable for conventional mapping.

Phil

Posted by: djellison Feb 21 2006, 08:26 AM

I feel your pain, beleieve me. It's an utterly shocking data set. I'm going to re-visit it once Bjorn has finished the next incarnation of img2png which will deal with FITS imagery as well

THere seemed to be hundreds of images of, well, nothing.

Doug

Posted by: Phil Stooke Feb 22 2006, 10:18 PM

This illustrates part of the shape-modelling process. A grid is fitted to the images... a tricky process. This version of the shape has some problems... it's not finished yet.

Phil

Posted by: tedstryk Feb 23 2006, 01:58 AM

There is a fairly good collection of stuff here:

http://pdssbn.astro.umd.edu/holdings/ds1-c-micas-3-rdr-visccd-borrelly-v1.0/document/

Posted by: Phil Stooke Feb 23 2006, 02:34 AM

Yes, but not properly documented, and the topo models are not in conventional mapping formats - they have to be projected into a planetocentric coordinate system to be converted to global maps.

Phil

Posted by: tedstryk Jul 16 2008, 05:09 AM

I have made two DS-1 compilations. The first contains one of each target it studied. The Jovian images were primarily for calibration, and the Mars images were to go along with much more valuable infrared spectra.

The second contains both of the Braille sets that did not miss. The first is a deconvoluted stack of the two CCD frames taken 15 minutes after the flyby. The second is from four frames obtained by the APS (Active Pixel Sensor) five minutes later. Thanks to spacecraft motion, it shows a very different angle on the lumpy asteroid. All frames are severely underexposed, which is why the quality is much poorer than the set from the CCD frames.

Posted by: tedstryk Jul 16 2008, 02:23 PM

I should add that the Braille images are shown at 4.5x original size.

Posted by: Phil Stooke Jul 16 2008, 05:18 PM

Stop it, Ted. You're making us look bad.

Phil

Posted by: tedstryk Jul 16 2008, 06:06 PM

Larry Soderblom send me the data I needed to properly process these. I would have never gotten anywhere from the salvaged mess on the PDS. It has been a goal of mine for a long time to get an image of Braille that actually looked like something.