How the Sky Turns

Say why the sky turns, and find your way round it from the pole stars.

8 guides · about 55 min

A line runs from a guide to the guides that build on it.

1. 1. Which Way Is East? 6 min Why does the Sun rise due east only twice a year?

   You’ll be able to say which way is east from where you stand, and where tonight’s Sun and stars will rise.

   Begin
2. 2. Finding the North Star 6 min How can one star tell you how far north you are?

   You’ll be able to find Polaris from the Big Dipper’s pointers, and read your latitude off it.

   Leads to

   Cassiopeia: The Other Pointer, The Big Dipper & Friends, Why the Sky Moves, The Chinese Sky (Sky Cultures), Polynesian Wayfinding (Sky Cultures)

   Begin Know it already? Find it outside
3. 3. The Southern Cross 6 min How do you find south from the stars, with no pole star to point the way?

   You’ll be able to find the south celestial pole from Crux and the Pointers.

   Builds on

   • Measure the Sky with Your Hand · Observing Skills. It uses “altitude”, which Measure the Sky with Your Hand explains.

   Leads to

   Why the Sky Moves, The Clouds of Magellan (Deep Sky), Polynesian Wayfinding (Sky Cultures), Shapes in the Dark (Sky Cultures)

   Begin Know it already? Find it outside
4. 4. Cassiopeia: The Other Pointer 5 min How do you find Polaris when the Big Dipper is too low to use?

   You’ll be able to find Polaris from Cassiopeia’s W when the Dipper is low.

   Builds on

   • Finding the North Star. It is a second way to Polaris, for nights the Dipper is low.

   Begin Know it already? Find it outside
5. 5. The Big Dipper & Friends 8 min How can one star pattern lead you to four bright stars?

   You’ll be able to hop from the Big Dipper to Arcturus, Spica, Polaris and Regulus.

   Builds on

   • Finding the North Star. It starts from the pointers to Polaris you used in Finding the North Star.

   Leads to

   Leo & the Spring Sky (Constellations)

   Begin Know it already? Find it outside
6. 6. Four Minutes Earlier 6 min Why does each star rise four minutes earlier every night?

   You’ll be able to say when a constellation will be back in your evening sky, and why stars rise four minutes earlier a night.

   Leads to

   The Star That Brought the Flood (Sky Cultures)

   Begin
7. 7. Why the Sky Moves 8 min Why isn’t your sky tonight the same as someone else’s?

   You’ll be able to say why the sky turns, why your latitude tilts it, and why the pole drifts over millennia.

   Builds on

   • Finding the North Star. The sky turns round the pole you learned to find.
   • The Southern Cross. The sky turns round the pole you learned to find.

   Leads to

   Celestial Coordinates, Before the Greeks (Sky Cultures), The Moon's Houses (Sky Cultures)

   Begin
8. 8. Celestial Coordinates 8 min How do you give a star an address a telescope can find?

   You’ll be able to read a star’s Right Ascension and Declination and find where on the sky that address is.

   Builds on

   • Why the Sky Moves. Its grid turns with the sky, round the pole Why the Sky Moves explains.

   Leads to

   The Ecliptic (Sun and Calendar)

   Begin

From other paths

Guides on this path build on these.

• Measure the Sky with Your Hand · Observing Skills · 5 min It uses “altitude”, which Measure the Sky with Your Hand explains.