[task #15911] Query NED extinction calculator

[Mohammad Akhlaghi]

Follow-up Comment #1, task #15911 (project gnuastro):

Just to make things easier to test, let me put an example of submitting a
query to the extinction calculator below where the coordinates are shell
variables (in degrees):


ra_deg=58.268000

dec_deg=35.591944

curl -oned.votable
'https://ned.ipac.caltech.edu/cgi-bin/calc?in_csys=Equatorial&out_csys=Equatorial&in_equinox=J2000.0&out_equinox=J2000.0&obs_epoch=2000.0&lon='$ra_deg'd&lat='$dec_deg'd&of=xml_main&ext=1'


But as they recommend, we should just not query in parallel or immediately
after each other! It can be expensive on their server and cause disruptions
for everyone! As they say, we should recommend the users to wait at least one
second between every query. 

This is fine for a small number of objects, but when there are (hundreds of)
thousands of objects in a catalog and we want the extinction on each, it can
be very slow and possibly expensive for NED also.

One solution may be this: people can define a grid over their field of view
(for example with boxes of size 0.5 degree), query NED for the extinction at
the centers of those boxes, then find the nearest box for each object in their
catalog and use that value. We should later add an 'astscript-' to do this.

I will ask them if it is possible to get the spatial resolution of each
extinction value to make the process above much more systematic.

    _______________________________________________________

Reply to this item at:

  <https://savannah.gnu.org/task/?15911>

_______________________________________________
  Message sent via Savannah
  https://savannah.gnu.org/