
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.
Animation: Black Hole Destroys Star
Almost Hyperspace: Random APOD Generator

Customized Star Charts Coming 1st Quarter 2027
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A stellar illusion
Behyar Bakhshandeh from Carlsbad, California The emission nebula IC 1318, also known as the Gamma Cygni Nebula, glows roughly 5,300 light-years away in Cygnus โ far beyond Sadr, the bright supergโฆ
ReadGhostly Cat's Head Nebula lurks within sight of NASA's Hubble, Webb
NASA's Hubble and James Webb Space Telescopes have captured a hauntingly dynamic star-forming scene, like a spectral form rising out of a cold mist. It lies within the vast Carina Nebula, a diffuseโฆ
ReadRubin observatory reveals two hidden companions of the Milky Way
Preview data from the recently completed NSF-DOE Vera C. Rubin Observatory in Chile point to a wave of discoveries that may complete the census of the Milky Way's neighboring galaxiesโincluding iโฆ
ReadCosmic microwave background offers evidence of gas flowing in galaxy clusters
The cosmic microwave background (CMB) is a faint glow in the universe dating back to roughly 380,000 years after the Big Bang, long before stars or galaxies emerged. Detecting this light and mappinโฆ
Read2026 Full Moon calendar: When to see the Full Moon and phases
The phenomenon of a Full Moon arises when our planet, Earth, is precisely sandwiched between the Sun and the Moon. This alignment ensures the entire side of the Moon that faces us gleams under sunlโฆ
ReadOct. 29, 1998: John Glenn returns to space
John Glenn became the first American to orbit Earth when he blasted off in Friendship 7 on Feb. 20, 1962. His flight made him an American hero during the heights of the Space Race, and the oldest mโฆ
ReadIs this our solar systemโs future? Scientists spot disk around dead star
Researchers have discovered a white dwarf surrounded by a debris disk with 2 separate rings. It offers a possible glimpse of our solar system's future.
ReadThe enormous oarfish could inspire new ways to explore the ocean
The giant oarfish has a remarkable fin that could inspire quieter underwater robots and open new possibilities for ocean exploration and conservation.
ReadVisible planets and night sky guide for October and November
Visible planets and night sky guide. Tomorrow morning, the moon will hang near Castor and Pollux, the twin stars of Gemini.
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