SED data model v0.92

[Jonathan McDowell]

A group led by myself and Doug Tody have been working on
the data model and data formats for the Simple Spectral Access Protocol,
which represents 1D spectra, time series and spectral energy distributions.
The document is still at a draft stage but has now reached a level
of maturity that it may be interesting for people to look at.
You can find it at
 http://hea-www.harvard.edu/~jcm/vo/docs/spec.html
and I'll put it on the twiki in the next few days.
   Jonathan