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.

✦  Astronomy Picture of the Day  ✦

Sutter's Mill Meteorite

April 28, 2012
Last Sunday's bright fireball meteor falling through skies over California and Nevada produced sonic booms over a broad area around 7:51 am. Estimates indicate the meteor was about the size of a minivan. Astronomer Peter Jenniskens subsequently recovered these fragments of a crushed 4 gram meteorite, the second find from this meteor fall, in the parking lot of the Henningsen-Lotus state park, not far from Sutter's Mill. This is now known as the Sutter's Mill Meteorite, the location famous for its association with the California Gold Rush. The meteorite may well be astronomer's gold too, thought to be a rare CM type carbonaceous chondrite, a type rich in organic compounds and similar to the Murchison Meteorite. To trace the meteor's orbit, details of its breakup, and aid in locating more fragements, scientists are also searching for video records. Security cameras across a wide area could have accidently captured the fireball event near 7:51 am PDT on April 22; e.g. California (SF Bay Area, Los Angeles, near Redding) and Nevada (Reno area, Tonopah), even in southern parts of Oregon and near Salt Lake City in Utah. If you have video footage of the event, please use the contact information here.

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✦  EarthSky  ·  Astronomy.com  ·  Phys.org  ✦
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