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Re: GJD to HJD



Re: GJD to HJD

    Please be careful about the accuracy of the result.  Your presented
algorism (which is likely designed for a quick calculation for visual
observations of eclipsing binaries) will not reach an accuracy of 0.00001 d.
(So presenting the results to 0.00001 d with "HJD" can be erraneous).
In order to attain this accuracy, you need proper corrections by planetary
perturbations.  [This is the reason why VSNET strongly recommend to use
GJD rather than HJD when reporing observation -- people usually has no
way to confirm the accuracy of conversions by each observer; nevwetheless
when analyzing and publishing the data by yourself, you surely need to
calculate HJD by yourself (at your own risk?).]

    BJD (barycentric JD) is a better solution if one needs 1 sec accuracy
(and even better is BJD(TT), considering the effect of leap seconds).

Regards,
Taichi Kato