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.
M16: Pillars of Creation
Customized Star Charts Coming 1st Quarter 2027
We respect your privacy. Unsubscribe at any time.
Why is Venus so bright in Earth’s sky?
You can't miss dazzling Venus in the west after sunset. It's the 3rd brightest object in the sky, after the sun and moon. But why is Venus so bright?
Read'Born-again' star offers rare chance to watch stellar evolution in real time
Astronomers have confirmed that one of the fastest-changing stars ever observed has entered a new stage of its evolution, offering a rare opportunity to watch a star's life unfold on human timescales.
ReadThe Sky Today on Wednesday, September 16: Triangle in the sky
Looking for a sky event this week? Check out our full Sky This Week column. September 15: View the false dawn Rising around sunset and highest in the early-morning hours before sunr…
ReadWebb reveals dynamic panorama of star formation, including smallest known brown dwarfs
This starry view of the nearby star-forming region IC 348 is one of the largest images released to date from NASA's James Webb Space Telescope. Using Webb, astronomers searched IC 348 for brown dwa…
ReadU.S. confirms it has weapons in orbit
In a groundbreaking announcement, the U.S. Space Force stated publicly on Monday, Sept. 14, that it currently has on-orbit weapons in space. Department of the Air Force Secretary Troy Meink’s…
Read2026 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 sunl…
ReadCubeSat instrument extends solar storm warnings 10x
The sun is the reason life exists on our small, blue planet. It provides solar radiation that warms the planet and ignites intricate biochemical processes like photosynthesis, producing oxygen for …
ReadVenus had a moon for nearly 2 billion years, scientists say
Venus had a moon a long time ago, scientists in the US and France say. It likely survived for nearly 2 billion years until Venus' gravity tore it apart.
ReadMercury is shrinking up to 30% more than expected
A new study shows Mercury is shrinking more than scientists first thought. They say the planet might have already shrunk up to 30% more than expected.
Read