All topics
4 topics · 24 guides · every one listed on the topic page it belongs to
The Moon
Phase, rise, set, distance and the illusions in between — what the Moon actually does, computed for a place and a date rather than described.
10 guides newest October 28, 2026 3 reference pages
Moon 10
The Sun and the seasons
Day length, solar noon, twilight and the off-center clock: why the earliest sunset is not on the shortest day, and why the equinox is not twelve hours.
5 guides newest October 23, 2026 1 reference page
Sun and Seasons 5
Eclipses and meteor showers
Shadow geometry and dust: which dates are real, where you have to stand, and the difference between a rate on paper and a rate in the sky.
3 guides newest October 27, 2026 1 reference page
Eclipses 2 Meteor Showers 1
The night sky
Constellations, precession, what your latitude hides from you, and how much of it light pollution has already taken.
6 guides newest November 3, 2026
Constellations 3 Observing 3