johanley / astro

Full source for astronomytonight.net, a site for amateur astronomers. The site has basic astronomy data for any location, and weather data for specific countries (the US and Canada). Customizable for your observing location.
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Charts - occultations not rendered correctly. #30

Open johanley opened 7 years ago

johanley commented 7 years ago

When an occultation is shown in a chart, by following a link from the main page, the rendering is off. The star is not close enough to the Moon's limb. It's off by ~20-40 minutes of time.

I checked the raw calc in ephem.js for the core calc of topocentric positions, and it seems ok (to within about 1 arcmin). The function EPH.apply_parallax_to_αδ(eph, wh) also seems ok.

So the bug is likely elsewhere. Size of the moon? Position of the star? The calc in code.js for the changes to ra, decl due to parallax?