release of a new version for the WD Observation Core Components data model and ObsTAP
Anita M. S. Richards
a.m.s.richards at manchester.ac.uk
Wed Mar 9 01:27:57 PST 2011
Here are some comments - mostly minor:
p14 Table 1 and elsewhere
What about Solar System or other data which cannot be described at all by
RA and Dec (because the body moves too fast, for example?) For example,
many ALMA observation sets will contain a moon as amplitude calibrator
along with extragalactic sources. It would be nice to have an option e.g.
'coosys other' if not all the options. Alternatively, one could allow RA
and Dec to be nil and identify Solar System objects by name and time-date.
p15 3.3.1 Data Product Type
Is it worth stating explicitly that visibility data is likely to be in
formats such as FITS, Measurement Sets (MS) or Science Data Models (SDM,
ASDM etc.) (usually distributed as tar or zip directories) - just so that
implementors can recognise the type of the latter, relatively new formats?
Should metadata only (as VOTable?) be included as a data product type, see
comment on 4.6
I find that the discussion in paras 3, 4 adds confusion to the nice clear
description in 3.3.2 - why are aggregates of multiple files limited to
levels 0 or 1 (e.g. MS, CASA-format images are directories but can be
completely calibrated and science-ready or even advanced products)?
Surely the approaches adopted are up to the provider. Either cut it down
or leave it out, or replace it with more fully described examples from
For e.g. MERLIN+VLA images, is 'MERLIN+VLA' acceptable a) logically b) is
'+' allowed or should it be _and_ or ...? - guideance on allowed
4.4 Unique identifier - does this mean unique within the Collection Name?
I am not sure that a combination of real observations is a 'software'
observation - I would reserve that term for simulated or model data. Back
to real combinations, surely it is up to the provide whether it gets a new
ID, but if the purpose of the ID is to allow tracing the observational
history this seems counter-productive. Omit this para?
4.6 Does 'data product' include metadata-only responses, e.g. when the
product is very large and the user should be warned or the data need
staging or user registration at a web form or whatever? (the Introduction
does mention 'retrieving or otherwise accessing')
4.12 ICRs only - see my first comment about the need to allow for SOlar
Thanks very much
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Dr. A.M.S. Richards, UK ARC Node, Room 3.135
Jodrell Bank Centre for Astrophysics, Alan Turing Building,
University of Manchester, M13 9PL
+44 (0)161 275 4243
MERLIN/VLBI National Facility, Jodrell Bank Observatory,
Cheshire SK11 9DL, U.K. +44 (0)1477 571321 (tel) 571618 (fax)
"Socialism or barbarism?" Rosa Luxemburg (1915)
On Mon, 7 Mar 2011, [ISO-8859-1] François Bonnarel wrote:
> Hi all,
> There are new topics discussed on the Wiki Page: discovery of polarization
> data and "NULL" value em_min em_max
> And of course the discussion is going on on previous topics
> Le 28/02/2011 21:51, Mireille Louys a écrit :
>> Dear DM and DAL WG member,
>> I released a new version of the so called ObsTAP WD, after a full revision
>> in collaboration with D.Durand , D.Tody and A.Michol.
>> Please go to
>> and give your comments on the same page.
>> The revision of the draft will take place from 2011 March 01 to April 02.
>> During this period , we plan to produce a revised version every Monday.
>> Thanks for reviewing this document and sharing your suggestions and
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