Wide or Narrow Schema for VOEvent?

[Alasdair Allan]

Roy Williams wrote:
> Here is a question regarding the reporting of positional information 
> for astronomical events. Should the reporting standard be
>
> (a) Very Narrow,
> meaning (for example) all positions in RA and Dec in ICRS frame seen 
> from center of Earth in the format H:M:S/D:M:S? In this case it is 
> easy for the event consumer to, for example, compute angular distance 
> between two events. But it would be too narrow to report some events 
> adequately (eg Martian volcano).
>
> (b) Very Wide,
> meaning that you can use galactic coordinates, or Jovicentric 
> coordinates, or coordinates in equinox B1870.0, or Martian 
> longitude/latitude. In this case, the event creator has wide freedom 
> to use a natural coordinate system. But the consumer must be able to 
> interpret something rather complex.
>
> How do we compromise between these extremes?

I think both are necessary, however you shouldn't be forced to specify 
everything unless you want to, all the additional information past a 
bare bones specification should be optional.

Al.