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 understand. Astronomy is where math, science, art, music, and words meet in a wondrous collision. In this section of our site, learn the basics of astronomy: from how a star chart is made, to projections and art that map the night sky, to how an astrolabe works just like it did thousands of years ago. Watch the North Star shift across centuries, explore how one sky has been mapped by many traditions, read what happened on this day in space, and see tonight’s moon for your location.
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 Large Magellanic Cloud in Ultraviolet
Customized Star Charts Coming 1st Quarter 2027
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Saturn’s south pole decagon confirmed! A mysterious 10-sided figure
Saturn’s south pole is now known to have a giant, evolving 10-sided wave, similar to the Saturn north pole hexagon. Read more about it here.
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The BepiColombo mission has been maneuvering its way into orbit around Mercury for 8 years. On September 3, it successfully released 2 orbiters.
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Nā ʻUhane Māhoe Huki Pū i ke Ola is the Hawaiian name given to NGC 7253—a pair of spiral galaxies caught in each other's gravity. Captured by the Gemini North telescope on Maunakea in Hawai'i…
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