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

Full Moons of August

August 30, 2023
Credit: Gianni Tumino
See this entry on NASA's APOD โ†’
Near perigee , the closest point in its almost moonthly orbit, a Full Moon rose as the Sun set on August 1. Its brighter than average lunar disk was captured in this dramatic moonrise sequence over dense cloud banks along the eastern horizon from Ragusa, Sicily. Illuminating night skies around planet Earth it was the second supermoon of 2023 . Yet again near perigee, the third supermoon of 2023 will also shine on an August night . Rising as the Sun sets tonight this second Full Moon in August will be known to some as a Blue Moon, even though scattered sunlight gives the lunar disk a reddened hue. Defined as the second full moon in a calendar month, blue moons occur only once every 2 or 3 years. That's because lunar phases take 29.5 days, almost a calendar month, to go through a complete cycle. Tonight an August Blue Moon will find itself beside bright planet Saturn.

Customized Star Charts Coming 1st Quarter 2027

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โœฆ  EarthSky  ยท  Astronomy.com  ยท  Phys.org  โœฆ
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