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.

✦  Astronomy Picture of the Day  ✦

Superstorm Sandy From Formation to Landfall

November 7, 2012
It was the largest hurricane ever recorded in the Atlantic Ocean. The cost of its devastation is still unknown. Pictured above is a movie of Superstorm Sandy taken by the Earth-orbiting GOES-13 satellite over eight days in late October as the hurricane formed, gained strength, advanced across the Caribbean, moved up the Atlantic Ocean along the US east coast, made an unusual turn west, made landfall in New Jersey, turned back to the north over Pennsylvania, and then broke up moving north-east over the northern US and Canada. Although Sandy's winds were high and dangerous, perhaps even more damaging was the storm surge of water pushed onto land ahead of Sandy, a surge that flooded many coastal areas, streets, and parts of the New York City subway system. Spanning over 1500 kilometers, US states as far west as Wisconsin experienced parts of the storm. Although Hurricane Sandy might have formed at any almost time, concerns are being raised that large storms like Sandy might become more common if water in the Atlantic continues to edge higher in power-enhancing surface temperature.

Customized Star Charts Coming 1st Quarter 2027

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✦  EarthSky  ·  Astronomy.com  ·  Phys.org  ✦
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