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.

โœฆ  Astronomy Picture of the Day  โœฆ

A Partial Lunar Eclipse

October 29, 2023
Credit: Orazio Mezzio
See this entry on NASA's APOD โ†’
What's happened to the Moon? Within the last day, part of the Moon moved through the Earth's shadow . This happens about once or twice a year , but not every month since the Moon's orbit around the Earth is slightly tilted . Pictured here, the face of a full Hunter's Moon is shown twice from Italy during this partial lunar eclipse . On the left, most of the Moon appears over exposed except for the eclipsed bottom right, which shows some familiar lunar surface details. In contrast, on the right, most of the (same) Moon appears normally exposed, with the exception of the bottom right, which now appears dark. All lunar eclipses are visible from the half of the Earth facing the Moon at the time of the eclipse, but this eclipse was visible specifically from Europe , Africa , Asia , and Australia , clouds permitting . In April, a total solar eclipse will be visible from North America .

Album: Selected partial lunar eclipse images sent in to APOD

Customized Star Charts Coming 1st Quarter 2027

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โœฆ  EarthSky  ยท  Astronomy.com  ยท  Phys.org  โœฆ
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