[Fwd: VOTimeSeries]

[Rob Seaman]

On Jul 2, 2007, at 1:59 PM, Doug Tody wrote:

>     o	The general spectrophotometric model upon which SSA is based,
> 	and which we have always intended to use for time series as
> 	well, uses STC (the data model not the XML serialization) for
> 	all reference frames, including time.  [...]
>
>     o	A general abstract data model such as STC, which could be used
> 	for many things, needs to be fairly complete in terms of what it
> 	can describe.  [...]

Ok, we've got the crude format from the napkin at the Arizona Inn.   
And we have the STC example, albeit with Arnold in absentia.  The  
third option is already legal VOEvent usage - to point to an external  
SSA reference.

We have been repeatedly assured SSA can address time series.  I just  
read through the SSA v1.01 draft again.  It resembles nothing so much  
as learning electricity and magnetism from Jackson's "Classical  
Electrodynamics" (or perhaps from any text using Gaussian units) -  
which is to say, a lovely theoretical scaffolding from which one is  
hard pressed to calculate any real world value as pedestrian as - say  
- a voltage.

What precisely would a VOEvent packet be pointing to with an embedded  
SSA reference?  Should we decide, rather, to embed native SSA time  
series serialized XML within a published VOEvent packet, what would  
it look like?  How would subscribers know what to make of either one?

I'm not sure a winning argument for the piratical, pragmatical  
VOEvent community is to be faced not only with adopting SSA, but also  
a different flavor of STC, for a purpose that can fit on a cocktail  
napkin.

Perhaps the answer lies herein:

> 	In other words, just because a general model defines something,
> 	does not need one has to use in an application of the model.

VOEvent is a container like VOTable or FITS from the point of view of  
SSA, right?  How do we proceed to realize the benefits of SSA  
compliance while minimizing the costs?

Rob

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