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

Satellites Behind Pinnacles

June 14, 2022
Credit: Joshua Rozells
See this entry on NASA's APOD โ†’
What are all those streaks across the background? Satellite trails. First, the foreground features picturesque rock mounds known as Pinnacles. Found in the Nambung National Park in Western Australia , these human-sized spires are made by unknown processes from ancient sea shells ( limestone ). Perhaps more eye-catching, though, is the sky behind. Created by low-Earth orbit satellites reflecting sunlight, all of these streaks were captured in less than two hours and digitally combined onto the single featured image , with the foreground taken consecutively by the same camera and from the same location. Most of the streaks were made by the developing Starlink constellation of communication satellites, but some are not. In general, the streaks are indicative of an increasing number of satellites nearly continuously visible above the Earth after dusk and before dawn. Understanding and removing the effects of satellite trails on images from Earth's ground-based cameras and telescopes is now important not only for elegant astrophotography , but for humanity's scientific understanding of the distant universe .

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โœฆ  EarthSky  ยท  Astronomy.com  ยท  Phys.org  โœฆ
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