Extension of the UCD list for Planetary Metadata and Radio data (ASKAP)

Discussion at last interops , namely Sao Paolo (Oct 2012), and Heidelberg ( mai 2013) have identified specific needs in the Planetary science community , to create and define semantic tags that can qualify/ classify metadata.

This work has been initiated by Baptiste Cecconni and coll. and is on the road map of the semantic WG.

A first document is issued below to start the discussion .

Please feel free to insert your comments in the section below.

Current discussions

Discussion and suggestions from ASKAP Project, CapeTown post meeting , Spring 2016

• Suggestions have been proposed and discussed via mailing list . See the summary table [https://wiki.ivoa.net/internal/IVOA/PlanetaryUCD/ValidationASKAP_UCDs_version2016July18.pdf
• New version of the WD for UCD list [https://wiki.ivoa.net/internal/IVOA/PlanetaryUCD/WD-UCDlist-1.3-20160718..pdf

Discussion at Strasbourg Observatory - 2014, April 03

F. Ochsenbein , Andrea Preite-Martinez, M. Louys + J. Berthier, J. Normand ( IMCCE)

we examined the first 2 sections of the draft on Solar System UCD Assessment and listed suggestions for new UCDs in the ucd list as shown in the UCD1+ proposed changes document .

Discussed the scope limit between data modeling and semantic tags classification, as realized in the IVOA UCD effort with J. B and J.L.

You are welcome to comment these proposed changes . These will be evaluated by the Maintenance UCD group during this spring period.

Discussion at Strasbourg Observatory - 2014, April 10

F. Ochsenbein , Andrea Preite-Martinez, M. Louys ( CDS, Strasbourg)

B. Cecconi, W. Thuillot ( Observatoire de Paris)

We followed the propositions summarized in the proposition document Solar System UCD Assessment

The new consolidated list proposed is available here UCD1+update- version 2 .

Discussion at Strasbourg Observatory - 2014, July 4

F. Ochsenbein , Andrea Preite-Martinez, S. Derriere, M. Louys ( CDS, Strasbourg)

Discussed the table of Solar System UCD Assessment, document version 5 , Some divisions for radio range coverage submitted. New UCD strings defined.

Current to do list for UCD update is available as attached here UCD1+update- version 3 .

from Baptiste - 2014, July 9

Update of Solar System UCD Assessment document to version 6 here Solar System UCD Assessment V6 (https://doi.org/10.5281/zenodo.3479165).

Discussion At Paris Observatory - 2015 Mars 25.

The UCDs proposed by the Europlanet/HELIO team has been accepted and included in the new version of the UCDs standard proposal. A few specific points were discussed:

• Comparision with SPASE metadata
  • SPASE metadata are forged to describe observations in the field of space physics (solar physics, magnetospheric physics, interplanetary medium, solar wind, ionosphere...). Solar System UCD Assessment V6 is proposing a series of mapping between SPASE keyword/values pairs and UCDs. The main comment is that the mapping is not straightforward. The scope of UCDs doesn't fit with a single SPASE metadata category, and the reverse is also true.
  • Using EPN_Core or Obs_Core descriptors can help to map UCDs with SPASE. Example:
    • spase:measurement_type = 'magnetogram' converts into UCD=phys.magField & dataproduct_type=image & target_name='Sun'
• Shall we include molecule names/tags in UCDs ?
  • The main concern about the new set of UCDs is the addition of molecular names into the em.line.* UCD group.
  • The origin of em.line.* UCDs are linked to the main spectral observation windows available for astronomy and cosmology, with ground based telescopes. Those are also the main Hydrogen bands, which is constituting most of the observed line signals in astrophysics.
  • The solar and planetary science community (especially use spase based observation platforms) are making use of all spectral ranges. Planetary scientists want to observe (and tag in their catalogs) all possible organic molecules, for instance. Solar physicists are observing all elements present in the solar photosphere, chromosphere and corona, used many ionization levels and isotopes. It is clear that the number of cases is very large if we want to be complete.
  • The first set of molecules proposed was not complete and several proposition of new molecular lines arrived when the proposal was sent out.
  • The risk of exponential increase of those UCDs is real.
  • It is decided that the Solar and Planetary additions of em.line.* UCDs are removed, and other solution will be discussed.
• Geodesy and Ephemeris UCDs
  • Discussion is postponed.
• Strategy for EPN-TAP services.
  • Atomic and Molecular data will be treated using VAMDC standards. The Europlanet/VESPA project team will handle this interaction (at least for epn-core)
  • Linking generic "measurement types" as in SPASE, or observational subjects as in the IAU Thesaurus, will also be studied by the Europlanet/VESPA team, as enhanced client interfaces on top of the epn-tap protocol.
• Types of Observations
  • Astronomical observations are only remote-sensing.
  • Solar system exploration includes also in-situ observations. There is no real consensus on the definition of an in-situ observation:
    • Space physicisits consider as in-situ a measurement of the local properties of the surrounding medium and as remote sensing a measurement of a distant phenomenon (electromagnetic waves, images and spectra)
    • Planetary scientists consider rover measurements (on the surface of a planet) as in-situ (even if they take images of the surroundings, such a a distant mountain on Mars), and space or earth-based observations as remote-sensing.
    • A discriminant criterion could be the time of observation compared to the time of the event. Simultaneity of those two epochs could define a "in-situ" observation. The simultaneity can still be questionned depending on the time scale.
  • Solar system exploration includes also active observations. This happens when the observation devices is exciting the medium and is observing the responses of the target. This is used for local plasma measurement (send a electric perturbation and observe how the local plasma is reacting), for planetary subsurface sounding (with radar instruments), for soil composition analysis on planetary rovers (with a laser beam sublimating the rock and a device sensing the response (gas, spectrum...))...
• Example files
  • The CDS team is asking for example files to check the consistency between the UCD definition and their usage, as well as improve their automated UCDs attribution tool. Those data files should be uploaded here.

Upload Test Data

CDS team will conduct tests on metadata consistency and UCD attribution. Please upload all avaliable files on the Upload your Test Data page.

-- BaptisteCecconi - 2015-03-25

Comments

I suggest you may write your comment like this and join your name like below ....

-- MireilleLouys - 2014-02-04