[fitsbits] Celsius unit in FITS keyword comments

[Norman Gray]

Greetings.

On 4 Mar 2016, at 3:42, Maren Purves wrote:

> Coming from the engineering end I very much agree with Steve.
>
> People who have to trouble shoot e.g. instrument behavior or telescope
> pointing sometimes want rather strange (at least for somebody who
> would only be interested in the actual description of the data)
> things put into FITS headers in rather strange units.

And for what it's worth, I agree, too, from the point of view of the 
IVOA VOUnits spec.

That spec went to some pains to avoid being prescriptive about what 
units may appear, limiting itself to being prescriptive only about the 
parsing of unit strings -- that is, lists of ASCII characters -- that do 
appear.  That prescription does have some implications for the choice of 
units, but it's expressed as far as possible in terms of 'known units' 
rather than 'permitted units', 'must be interpreted consistently with' 
rather than 'must be interpreted as', and 'preferred units' where there 
is a choice.

If the extent of this non-committal position isn't clear from the spec, 
that would I think warrant a revision of the text.

All the best,

Norman


-- 
Norman Gray  :  https://nxg.me.uk
SUPA School of Physics and Astronomy, University of Glasgow, UK