
The Rhythm of the Spheres
Reading the Night Sky
Wandering in Astronomy
The night sky is the oldest pattern of man, and every culture reads it differently. The stars above keep silent time, moving to a rhythm we are just now beginning to undertand. Astronomy is where math, science, art, music and words meet in a wonderous collision. On this section of our site, learn the basics, from how a star chart is actually made, to projections and art that map the night sky, to how astrolabe work the same as they did thousand years ago. Watch the North Star shift across centuries and explore how one sky has been mapped by many traditions. Check what happened on this day in space, or see tonight’s moon drawn for where you stand.
Map the Stars
The math behind star charts, with a projection explorer and a working astrolabe.
The Moving Sky
How the sky shifts across centuries, with a precession clock you can run.
The Traditions
One sky reads many ways, with a same-sky overlay of the world’s constellations.
This Day in the Stars
The sky’s events, discoveries, and lore tied to today’s date
The Moon Tonight
Its phase and face, drawn live for where you’re standing.
The Hydra Cluster of Galaxies

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