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Ephemeris Times

Wed, 04/17/2019 - 16:12

Hello!

Are the times listed in the ephemerides of EBs geocentric, heliocentric, or barycentric?  Also, I'd appreciate a reference to how the VSX calculates these times.

Cheers and Thanks!

Matt

Sebastian Otero
Affiliation
American Association of Variable Star Observers (AAVSO)
Wed, 04/17/2019 - 17:24
Sources for VSX epochs

>>> Are the times listed in the ephemerides of EBs geocentric, heliocentric, or barycentric?  Also, I'd appreciate a reference to how the VSX calculates these times. <<<

Hi Matt,
Unfortunately it depends on the source. Most of the epochs in VSX come from the literature and old epochs of minima coming from the GCVS and old papers are JD.
Results from most recent papers are in HJD and that is what we adopt for any new submission that we approve. We request epochs of minima be given in HJD.
But most Kepler papers use BJD so there is a mix of epochs, you should dig into the relevant sources (see the reference section and revision comments to identify the sources) to know more about the published epochs. As I mentioned, VSX does not calculate epochs but mostly takes them from other sources.

Cheers,
Sebastian