Re: [weewx-user] Announcing weewx-skyfield (a modern almanac), weewx-loopdata (live report tags), and weewx-celestial (a live sky display)

['John Kline' via weewx-user]

Hi Ian,    That one is expected: the earth is the observer in the almanac, not one of the bodies it serves, so there's no $almanac.earth — same as PyEphem, which has Sun, Moon, and Mercury through Pluto, but no Earth body. Earth's heliocentric longitude is still available, though, just under a different name. Since the sun's own heliocentric coordinates are undefined (it sits at the origin), $almanac.sun.hlongitude reports the Earth's heliocentric ecliptic longitude — a convention inherited from XEphem/PyEphem. So: $rad($almanac.sun.hlongitude.raw) completes your set of nine, computed in the same frame as the others.     This is deliberate, and it's a policy: weewx-skyfield aims to be a drop-in replacement for WeeWX's built-in PyEphem almanac. Every tag that worked before keeps working and means the same thing — the test suite carries a permanent parity audit that evaluates everything the built-in almanac could do against both engines. Where we  knowingly deviate (only where PyEphem is measurably wrong, e.g. Jupiter's central meridian longitudes), each case is documented in the README under "Differences from PyEphem". So when a tag like $almanac.earth doesn't resolve, that's fidelity to the original almanac rather than a gap. Regards, John On Jul 29, 2026, at 11:54 PM, Ian <weatherboy...@gmail.com> wrote: Hi again John, Just one more thing All these values are resolving except for earth $rad($almanac.mercury.hlongitude.raw) $rad($almanac.venus.hlongitude.raw) $rad($almanac.earth.hlongitude.raw) $rad($almanac.mars.hlongitude.raw) $rad($almanac.jupiter.hlongitude.raw) $rad($almanac.saturn.hlongitude.raw) $rad($almanac.uranus.hlongitude.raw) $rad($almanac.neptune.hlongitude.raw) $rad($almanac.pluto.hlongitude.raw) Thanks Ian On Wednesday, July 29, 2026 at 9:13:40 PM UTC+1 Ian wrote: Hi John, I don't no how many times I read through that and I missed it! Thanks Ian On Wednesday, July 29, 2026 at 8:28:46 PM UTC+1 John Kline wrote: Hi Ian, Thanks for the kind words! Good news: it's already there. $almanac.moon.parallactic_angle works today (since 1.0), returning radians as PyEphem did. For degrees: #import math $("%.1f°" % math.degrees($almanac.moon.parallactic_angle)) Example: #import math ... <p>Moon parallactic angle: $("%.1f°" % math.degrees($almanac.moon.parallactic_angle))</p> It works for any body, not just the moon. Note: I could make $almanac.moon.parallactic_angle.degrees work (rather than having to concrete it). I return radians for PyEphem compatability; but I could keep that and still support the .degrees. I’ll probably do that in the next release. Cheers, John > On Jul 29, 2026, at 12:06 PM, Ian <weathe...@gmail.com> wrote: > > John, > > This is really tremendous stuff. I wondered is there any chance that you could add a tag for moon's parallactic angle. > Crongratulations and thank you > > Ian -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+unsubscr...@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/weewx-user/96983ce1-6398-447d-9f19-1aeeae74faf3n%40googlegroups.com. -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+unsubscr...@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/weewx-user/161FB99E-9729-48AC-B1D3-B1F5BC5A4764%40johnkline.com.