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

Jupiter and Ring in Infrared from Webb

April 2, 2025
Credit: NASA , ESA , CSA , STScI ; Processing & License: Judy Schmidt
See this entry on NASA's APOD โ†’
Why does Jupiter have rings? Jupiter's main ring was discovered in 1979 by NASA's passing Voyager 1 spacecraft, but its origin was then a mystery. Data from NASA's Galileo spacecraft that orbited Jupiter from 1995 to 2003, however, confirmed the hypothesis that this ring was created by meteoroid impacts on small nearby moons. As a small meteoroid strikes tiny Metis , for example, it will bore into the moon, vaporize, and explode dirt and dust off into a Jovian orbit. The featured image of Jupiter in infrared light by the James Webb Space Telescope shows not only Jupiter and its clouds , but this ring as well. Jupiter's Great Red Spot (GRS) -- in comparatively light color on the right, Jupiter's large moon Europa -- in the center of diffraction spikes on the left, and Europa's shadow -- next to the GRS -- are also visible. Several features in the image are not yet well understood , including the seemingly separated cloud layer on Jupiter's right limb.

Celestial Surprise: What picture did APOD feature on your birthday? (post 1995)

Customized Star Charts Coming 1st Quarter 2027

We respect your privacy. Unsubscribe at any time.

โœฆ  EarthSky  ยท  Astronomy.com  ยท  Phys.org  โœฆ
Astrophotography Nov 11, 2026

ZWO introduces the Seestar S30 Plus

ZWO has added a new entry point to its smart telescope lineup. The Seestar S30 Plus went on sale Nov. 10 for $499 โ€” $474 for a limited time โ€” undercutting the S30 Pro by $200 and making it the โ€ฆ

Read
Astronomy Nov 11, 2026

Centaurus A in the spotlight: Plasma simulations reproduce black hole jets' mysterious bright edges

Around 12 million light-years away, the supermassive black hole of the galaxy Centaurus A is hurling two enormous plasma jets into space at nearly the speed of light. These so-called jets are brighโ€ฆ

Read
Nov 11, 2026

Taula eclipse

Josh Dury, taken from Menorca, Spain The Aug. 12, 2026, total solar eclipse sets over Talatรญ de Dalt, a late Bronze Age settlement on the Spanish island of Menorca. The Sun’s partial phases โ€ฆ

Read
Observing Nov 11, 2026

2026 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 sunlโ€ฆ

Read
Astronomy Essentials Nov 11, 2026

Visible planets and night sky guide for November

Visible planets and night sky guide: Watch our video to discover the Leonid meteor showerโ€™s spectacular history, what to expect in 2026, and how to catch the show!

Read
Space Nov 11, 2026

This active asteroid has grown a tail! What happened?

Active asteroid 1995 BJ4 has grown a cometlike tail, leaving astronomers wondering whatโ€™s happening.

Read
Space Nov 11, 2026

A runaway star speeds in an unusual direction

A runaway star moves faster and in a different direction from the general stream of stars in our Milky Way Galaxy. Why?

Read
Astronomy Nov 11, 2026

Earliest known compact quasar pair poses a black hole growth puzzle

The oldest pair of compact quasars ever observed has been found only 900 million years after the Big Bang. Scientists say there is no theoretical explanation for how the pair of actively feeding blโ€ฆ

Read
Astronomy Nov 10, 2026

How the cosmic environment depletes galaxies of their gas

An international team of researchers, led by Jonathan Freundlich (University of Strasbourg, Astronomical Observatory), has revealed how a dense cosmic environment depletes galaxies of their gas. Byโ€ฆ

Read