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(Updated Aug 2017 with Aladin v9.6 and java 1.8, SE)
Use case by Sébastien Derrière, CDS (June 2015), enlarged with comments and implementation notes
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Summary : Build a 3D spherical HiPS off of Io, and overplot surface features from USG USGS catalogue.
This is an extension of Use Case #28 of Aladin Beta Test page (requires Aladin v9 and up):
http://aladin.u-strasbg.fr/java/Demo/AladinDemo.gm
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• extract io_bjj_0dd.tif, convert to jpg
In the terminal, type:
> convert io_bjj_0dd.tif io_bjj_0dd.jpg
• Load jpg image in Aladin as local file
Image size is 2880 x 1440
Set In the Frame drop menu (next to Location field) to Planet
• Apply astrometric solution:
, select Planet (will plot Lon-Lat coordinates, E-handed)
• Tie a coordinate frame to the image:
Click Image > Astrometrical calibration
Use And use parameters:
Central Central pixel = 1440.0 720.0
Pixel Pixel angular size = 7.5' (= 360/2880*60)
Projection Projection = CARTESIAN
Rotation Rotation = 0°
RA RA symmetry : False
• Convert to HiPS :
Tool > Convert current image to a HiPS
Apply grid= False (default value, this is essential)
• Build a HiPS (Hierarchical Progressive Survey) from the image:
Tool > Generate a HiPS based on… > current image
It will plot after computation. Then overplot grid (Comm-G or bottom left icon), pan around, zoom in/out ...
> Type Comm-G to overplot coordinate grid
> Beware that longitudes are handled as Righ Ascensions (inverted)out…
Projection is normally set to Spherical, but you can play with this also
Longitudes should be correctly set, ie increasing towards the left, but may plot as xxE and xxW in °
• Adding catalogue features:
Planetary Download USGS planetary nomenclature downloaded from
ftp://pdsimage2.wr.usgs.gov/pub/pigpen/nomenclature/nomenclature_all_feb2004.zip
Extract nomenclature_all_feb2004.dbf
and convert to csv with (e.g. using http://dbfconv.com/
Little cleanup of csv file, and load it in TOPCAT.
> )
Remove EOL character <NULL> from csv file in TextMate or another handy editor
• Filter Load it in TOPCAT as csv file
• Select Io features only by creating a subset:
Click on red/violet icon (subsets), add a filter (Plus icon) with parameters (name: io, expression: SA=="io")
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Then select "Row subset" io in TOPCAT main window
=> 221 lines out of 8395 in io subset
> Click on red/violet icon, add a filter
& "plot subset" io in main window
Choose io Row subset in main TOPCAT window and broadcast Broadcast to Aladin via SAMP (Interop > Send table to…)
• Right-click the catalogue plane in Aladin, select Column Information
Click on Coord for LATITUDE and LONG360, pretending they are Information…
Define source for coordinates carefully by clicking the Coo column and selecting a value in the drop list:
LATITUDE (col 16) => DE
LONG360 (col 18) => RA
(we're telling Aladin to handle these columns as its usual DEC and RA, respectively.)
• Create a dedicated filter in Catalog > Create new filter:
In advanced Select Advanced mode, use the following expression :
> this is Catalogue menu item / create new filter / advanced modeand type / copy:
{
# scale is 113.3 arcsec/km
draw ellipse(113.3*${DIAM}, 113.3*${DIAM}, 0) rainbow(${AD},1979,2003)
draw ${NAME} rainbow(${AD},1979,2003)
}
Displays Clicking Apply will display names and sizes of surface features, color-coded by according to year of discovery.
• Remaining issues :
Defaut orientation of RA or longitudes in Aladin is different
from the one used in planetary science, therefore the surface
is viewed as from within the planetary body, not from outside.
> Other pb on my side :
- long180GIS does not work either?
- Filters are not saved ?
- Graphic mix up when ploting 2 views simultaneously
- Comment: healpix only supports spherical projections, not ellipsoids
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resolution = 1°/pixel
size= 2 * pi * R / nb pix = pi * 3390. *2 / 360. = 59.2'
Can be enlarged to 60' ?
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Aladin 9 / java 1.6 / Mac OS: often blocking at launch, but not always
Mars image is now OK
"Save image" does not include the projected image (only the sphere frame)!
Play with the 3D model in Pan mode
• Double click on nomenclature in Aladin's stack to see the catalogue
Clicking an item will center it on the map
The feature under your pointer in the list or map in Aladin will be highlighted in the original TOPCAT table.
Feb 2016, Aladin 9
• Application by Mikhail Minin with Aladin Lite:
http://epn1.epn-vespa.jacobs-university.de:8080/MARS/
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With this method, your will be able to create and publish deep HiPS (at any resolution) rather that just a low resolution planet map.
Notice that you can already display your HiPS in various projections (SINUS, AITOFF, MOLLWEIDE, AITOFF, CAR, ...) via the Propertie button in Aladin.
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(*) The WCS header is presently sky oriented and you will have to adapt WCS to your image collection.
For instance, if you take this unique image http://i.stack.imgur.com/ojwD8.jpg (the earth in cartesian projection), you may use this following calibration file ojwD8.hhh:
NAXIS1 = 2048
NAXIS2 = 1024
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