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

Mars Marathon by Perseverance

June 27, 2026
Credit: NASA , LPL (U. Arizona) , MRO , HiRISE
See this entry on NASA's APOD โ†’
In this recent HiRISE view from the Mars Reconnaissance Orbiter, the little green dot indicated on the surface of the big Red Planet is the Perseverance Mars rover. Recorded on June 13, the car-sized, six-wheeled robot was imaged a day before completing a Martian marathon, traveling a total distance of 26.218 miles ( 42.195 kilometers ) since it began exploring the surface of Mars. That equivalent marathon distance was achieved by Perseverance on its mission sol (Martian day) 1,890, after about 5 Earth years and 4 Earth months of driving. Perseverance is continuing to hunt for biosignatures. In the HiRISE image, the Mars rover's tracks can be seen leading to its location in an area west of its landing site in Jezero crater near an ancient river delta .

Customized Star Charts Coming 1st Quarter 2027

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โœฆ  EarthSky  ยท  Astronomy.com  ยท  Phys.org  โœฆ
Observing Nov 4, 2026

The Sky Today on Wednesday, November 4: Venus and Spica stand close

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Human World Nov 3, 2026

Crew emerges from Mars habitat simulation after yearlong test

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Astronomy Nov 3, 2026

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Nov 3, 2026

Sailing through Cassiopeia

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Observing Nov 3, 2026

2026 Full Moon calendar: When to see the Full Moon and phases

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Astronomy Nov 3, 2026

A tiny shift exposes a cold brown dwarf masquerading as an early galaxy

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Astronomy Nov 3, 2026

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Space Nov 3, 2026

Swift spacecraft fiery reentry expected within the next 24 hours

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Space Nov 3, 2026

When will the Blaze Star erupt? Will neutrinos give us a warning?

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