I have developed methods for shape modelling of small solar system bodies which are ideally suited for use with low resolution images. The models are created by modifying an initial ellipsoidal model until it duplicates the appearance of all images in a data set. The shapes of limbs and terminators are the principal source of shape information, but where images overlap the model may be refined by correcting for parallax between surface features and the shape model. This method, greatly refined, is now used by the imaging teams for NASA planetary spacecraft.
In addition, I have devised map projections for use with irregularly shaped objects. These are derived from the azimuthal class of projections, including the familiar orthographic and stereographic. Here is an example of a map of asteroid 951 Gaspra to illustrate the appearance of this kind of map:
(Click on image to view at full size.)
Note: where shape models are not provided, the data are insufficient to constrain the shape beyond a rough ellipsoidal model. I thank colleagues who have made shape models available, as indicated below.
Note regarding detailed maps: each sheet spans 60 degrees, and 14 sheets give global coverage. All these versions are both reduced and compressed from the originals. One pixel spans 10 m on the body itself. Print at 25 pixels/cm for the true (1:25,000) scale. All files on my website including these are in the public domain, but please give proper credit.
Note on asteroid shapes: shapes of radar-imaged asteroids are by Scott Hudson.
If you want to convert to the format I use, contact me.
4 Vesta .....
MAP..... DESCRIPTION.....
SHAPE MODEL... courtesy Peter Thomas, Cornell University...
243 Ida .....PHOTOMOSAICS.....
DESCRIPTION.....SHAPE MODEL... courtesy Peter Thomas, Cornell University...
243 Ida .....GEOLOGICAL MAP.....
253 Mathilde .....PHOTOMOSAICS.....
DESCRIPTION.....SHAPE MODEL
253 Mathilde .....POLAR PHOTOMOSAICS.....
DESCRIPTION
253 Mathilde .....PHOTOMOSAIC (cylindrical projection).....
DESCRIPTION
951 Gaspra .....MAP.....
DESCRIPTION.....SHAPE MODEL
951 Gaspra .....PHOTOMOSAICS.....
DESCRIPTION
951 Gaspra .....MAP (cylindrical projection).....
DESCRIPTION
951 Gaspra .....GEOLOGICAL MAP.....
DESCRIPTION.....
951 Gaspra .....detailed map, sheet 2.....
1620 Geographos .....MAP.....
SHAPE MODEL... (link to Scott Hudson's shape model)
2063 Bacchus .....
SHAPE MODEL... (link to Scott Hudson's shape model)
4179 Toutatis .....MAP.....
DESCRIPTION.....
SHAPE MODEL... (link to Scott Hudson's shape model)
4179 Toutatis .....
MAP (cylindrical projection).....
DESCRIPTION
4769 Castalia..... MAP.....
DESCRIPTION.....
SHAPE MODEL... (link to Scott Hudson's shape model)
1998KY26 .....
SHAPE MODEL... (link to Scott Hudson's shape model)