Mosaic code update:
mapping the kronian
magnetosphere
Henrik Melin
Planetary and Space Science Division
Space Environment Technologies
UVIS Team meeting 09/01/2007
Old and new IDL code
a comparison
• 3367 lines of code
• Fortran style interface
• Every instance of a
geometric setup a
special case
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342 lines of code
IDL style interface
Cache implementation
Generalized approach
to dealing with
geometry by using
polygons
Input parameters
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Length of the side of the square grid
Number of grid elements
Target, e.g. ‘SATURN’
Flat-field array
Files to process
– Properties of the NCDF files: time, integration
time, compression etc from file header.
Output parameters
• A data cube x, y is spatial coordinates and z
is the spectral dimension
INITIAL RESULTS
Cassini pre-SOI system scans
1
2
3
4
Reflected sunlight dataset 1
Reflected sunlight dataset 2
Reflected sunlight dataset 3
Reflected sunlight dataset 4
Lyman Alpha dataset 1
Lyman Alpha dataset 2
Lyman Alpha dataset 3
Lyman Alpha dataset 4
Oxygen (1304Å) dataset 1
Oxygen (1304Å) dataset 2
Oxygen (1304Å) dataset 3
Oxygen (1304Å) dataset 4
Remaining issues
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Intensity calibration - flatfielding
How do I deal with evil pixels?
What is the smallest usable time resolution?
What is the optimal grid resolution?