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Aladin V10 demo with Mars data + EPN-TAP services + discovery tree

(Updated May 2019, v10.128; syntax for filters has evolved)

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  • Superimpose Mars data from a VOTable
    1. load http://aladin.u-strasbg.fr/java/demo/MarsInfo.xml
      this is a USGS catalogue of Martian features, all type mixed (selection of craters, plus volcanoes, regions, vallis, etc)
      double click on MarsInfo (the name, not the icon) in Aladin stack to see table
    2. load and activate filter to present these data: http://aladin.u-strasbg.fr/java/demo/mars_feature.aj
      this will draw ellipses as feature contours, with names
      filter can be seen by right-clicking the "Crater" item in Aladin stack, then Properties / Advanced mode / Crater
      2019 - now accessed by Menu Item: Catalog / Create a Filter; copy filter text only between { } in this field

    3. check match between feature contours and map (actually inaccurate)
       IndeedIndeed: many features are not elliptical, but plus there are actual shifts - related to different coordinate systems in map and catalogue (TBC)? - looks like a planetocentric vs planetographic issue



  • Search and query EPN-TAP services available
    1. Filter discovery tree (left panel) by specifying a keyword in field "select":  "obspm" for PADC services, or (better here) "mars"
    2. Select service  jacobsuni→Mars_craters, click on this line in the tree + check box "by critera" and press "Load" in dialog
    3. this opens a TAP query window; select table "mars_craters.epn_core"
    4. Click "Set ra, dec" and choose C1min and C2min
    5. Add constraint "diameter >  200" in the TAP query
    6. Add a filter as in the previous Io example (Aladin & planetary surfaces):

      #AJS
      filter Filter1 {{
      # scale is 64.5 arcsec/km
      draw ellipse(64.5*${diameter}/2, 64.5*${diameter}/2, 0) rainbow(${degradation_state},0,3)
      draw ${feature_name} rainbow(${degradation_state},0,3)
      }
      }2019 - again, copy filter with only 1 level of  { } 

    7. Check match with map features



  • Note: comment on TAP table
    • s_region is visible in the table with a button called FOV.
    • Clicking sends the view to the correct location (from C1/C2); 
    • features in display are highlighted in the table (FoV of different color)
    • 2019:  the the s_region contour is also plotted and highlighted; "Show associated FOVs" in Properties panel plots all s_region
  • Note: Comment on the feature catalogue from USGS
    • This is obviously a selection for test purpose
    • UCDs are picked up so that Aladdin loads the table easily, but are fake (coordinates in particular)
    • Includes a link to an USGS web service that does not work for some reason.
      It seems that USG have changed their information system recently, see here: https://planetarynames.wr.usgs.gov/SearchResults?target=MARS
      they now include kml footprint on each feature page.
  • New branch "Solar System" to discovery tree
    1. Load URL (in Location field) http://alasky.u-strasbg.fr/Planets/HipsList
    2. Open branch "Solar System" (was "/local/Planet")
    3. 2019: All planetary HiPS have been regenerated correctly and plot directly in the correct orientation (longitude = ascending) 
      (initial comment:) Note that all HiPS presented here (except for Mars) have very low resolution and don't allow the user to invert longitude direction - for an unknown reason, may be related to the way the HiPS is generated. They should all be replaced by versions similar to Mars THEMIS HiPS (classic Hipsgen generation method)

Extra items

  • Concerning HEALPix density maps in TOPcat, see: https://arxiv.org/abs/1611.09190 (+ apply to ex. about VIRTIS coverage on 67P in VESPA PSS paper)
  • Identify / complement Calabreta & Greissen values to indicate coordinates on Solar System bodies: 4 characters, ending in LT or LN (eg MALT/MALN) - only main objects (including Sun) + a generic value for body fixed frames. Have it validated by IAU fits commission.
  • Projections : see Chiara's LPSC abstract for a selection among ISIS projections
  • See possible usage of MOCs on planetary surfaces. In particular to: accelerate computation of intersections between datasets (faster than s_region, available in tools rather than server, and more general); get backward references to source data; data fusion, including spectral dimension.
  • Usage of HipsCube, e.g. for atmospheric data
  • Open WMS images in Aladin for plot (like in Mizar)?

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