VOEvent Update

[Roy Williams]

Hi Tim

> Would we get that if we allowed STC to be embedded in WhereWhen? 

In moving VOEvent from version 1.1 to 2.0 in 2009, we greatly simplified the description of the WhereWhen element, by removing the links to the STC schema. This was because many of the XML tools could not handle the complexity of the STC schema. 

We moved to a single string to describe the coordinate system, such as "UTC-FK5-GEO", for the time, celestial sphere, and Earth surface, respectively.

Rather than changing the WhereWhen section, moving objects and satellites could be described in the What section in a data model -- with a typed Group of Params and Tables.

Roy