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.
M51: The Whirlpool Galaxy
Customized Star Charts Coming 1st Quarter 2027
We respect your privacy. Unsubscribe at any time.
The Sky Today on Thursday, November 12: An open cluster in Perseus
Looking for a sky event this week? Check out our full Sky This Week column. November 11: Venus comes to a halt The constellation Perseus is famous for its bright Double Cluster, but…
ReadIndependent technique validates landmark M87* image
The 2019 Event Horizon Telescope (EHT) image was the work of hundreds of scientists and captured the first direct view of a black hole's shadow—becoming one of the most recognized scientific imag…
ReadZWO 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 — $474 for a limited time — undercutting the S30 Pro by $200 and making it the …
ReadCentaurus 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 brigh…
ReadTaula eclipse
Josh Dury, taken from Menorca, Spain The Aug. 12, 2026, total solar eclipse sets over Talatí de Dalt, a late Bronze Age settlement on the Spanish island of Menorca. The Sun’s partial phases …
ReadVisible planets and night sky guide for November
Visible planets and night sky guide: Watch our video to discover the Leonid meteor shower’s spectacular history, what to expect in 2026, and how to catch the show!
ReadThis active asteroid has grown a tail! What happened?
Active asteroid 1995 BJ4 has grown a cometlike tail, leaving astronomers wondering what’s happening.
ReadA 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?
ReadEarliest 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 bl…
Read