IVOA and ADASS?

[Steve Allen]

On Wed 2008-07-02T11:18:01 -0700, Roy Williams hath writ:
> (2) On the matter of "time", can we also reduce scope? Can we agree on a
> single system like Julian Day? If we need to generalize to Ganymedian
> siderial time, then we are lost. (IMHO).

I don't think a single time scale is feasible.

In the broadest sense of recommendations from the IAU I offer that the
single time scale that should be applied to all astronomical human
endeavour in this era is barycentric julian date using TCB.

But not even the solar system ephemerides folks agree, for they're
still using TDB.  For most of the rest of us we don't have experience
using software that will reliably do the 4-vector transformation from
observatory/UTC to barycenter/TxB.

--
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