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Polaris HA screenshot


This is a HTML page with Javascript to compute Polaris Hour Angle for your current location and local date-time. This page will work in any ES5/6 conformant browser (tested in Palemoon/Linux and Chrome/Android).

It is to be used with a polar finder in the field alignment process for equatorial mounts.

I was fed up by Android bloated (no less than 1.5MB) apps for the purpose, so I searched for backing equations and integrated them as a web page.

Download: polfinder ha greenwhich.html

Usage: First, make a new copy for each of your observing locations, and edit each file to change the location's name and longitude (arc minute is enough). Then open the page in your browser ; Refresh the page to recalculate with the current time.


© Fabien COUTANT

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