A modest proposal for VOEvent

[Arnold Rots]

Orbit ephemerides can be expressed perfectly well in WhereWhen since
they are supported by STC.
See, e.g.: http://hea-www.harvard.edu/~arots/nvometa/STC/Orbit.xml

Why reinvent it and have yet-another-way-to-express-the-same-thing?

  - Arnold

Roy Williams wrote:
[ Charset ISO-8859-1 unsupported, converting... ]
> Perhaps we can use the existing VOEvent structure, with no need to add 
> any extra schema (see below). The Group type (eg ="ephemeris") tells the 
> software what Params to expect inside. Everything can be represented 
> with what we already have!
> 
> Roy
> 
> ----------------------------------
> 
> <What>
> <Group name="Pluto" type="orbit">
>  <Param name="q"             unit="AU"  dataType="float" value="123" />
>  <Param name="e"                        dataType="float" value="123" />
>  <Param name="i"             unit="deg" dataType="float" value="123" />
>  <Param name="node"          unit="deg" dataType="float" value="123" />
>  <Param name="time_peri_MJD" unit="MJD" dataType="float" value="123" />
>  <Param name="arg_peri"      unit="deg" dataType="float" value="123" />
>  <Param name="epoch"         unit="MJD" dataType="float" value="123" />
>  <Param name="src" value="1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 
> 19 20 21" />
> </Group>
> 
> Then we would add geocentric ephemeris
> 
> <Group name="E012" type="ephemeris">
>  <Param name="ephem_type"                             value="geocentric"/>
>  <Param name="ra"         unit="deg" dataType="float" value="123" />
>  <Param name="dec"        unit="deg" dataType="float" value="123" />
>  <Param name="mjd"        unit="day" dataType="float" value="123" />
> </ephemeris>
> 
> And the detections used to derive the orbit
> 
> <Group name="D023" type="detections">
>  <Param name="ra"  unit="deg" dataType="float" value="123" />
>  <Param name="dec" unit="deg" dataType="float" value="123" />
>  <Param name="mjd" unit="day" dataType="float" value="123" />
>  <Param name="obscode"                         value="123" />
> </Group>
> </What>
> -- 
> 
> California Institute of Technology
> 626 395 3670
> 
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Arnold H. Rots                                Chandra X-ray Science Center
Smithsonian Astrophysical Observatory                tel:  +1 617 496 7701
60 Garden Street, MS 67                              fax:  +1 617 495 7356
Cambridge, MA 02138                             arots at head.cfa.harvard.edu
USA                                     http://hea-www.harvard.edu/~arots/
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