Unit tests

This page tests some of the functions and algorithms the site relies on. In most cases, you should see only tiny differences between the reference values and the values calculated by airmass.org. The ratio column is highlighted in green for quantities that are accurate to better than one part in a million, yellow for better than one part in a thousand and orange for worse than one part in a thousand. For the purposes of testing, the results of getLunarSigmas() shown here use all the coefficients listed in Meeus, while in the actual observability calculations, smaller periodic terms are dropped. The accuracy in practice is about 1 per cent.

airmass.org version number: 2745-0dbff1a (2024-03-08 15:06:10 +0000), run on php 8.1.27


Solar event times

Results from airmass.org are compared to results from PHP date_sun_info() for four locations (London, Auckland, Los Angeles and Tromsø) on today's date (2024-04-13), and 2021-01-01.



Browser compatibility

This table lists the major javascript functionality that this site relies on. These features should all be available in recent versions of widely-used browsers. If any are shown as not available, you may find that the site does not work as expected for you.