How to read a Star Chart

| Basic Celestial Phenomena | Constellations | Planetarium |

Get a current star chart

• Available at the OBU Planetarium
• Available online:
  • StarDate
  • Abram's Planetarium

How to read a Star Chart

1. Face south
2. Hold the chart over your head, with its north horizon behind you and its south horizon in front of you.

• Read a road map looking down, but read a star chart looking up!
  If you try to read a star chart looking down, when north is at the top and south is at the bottom you will discover that east is not on the right and west is not on the left, as they would be for a road map. This surprising anomaly vanishes, however, if you hold the chart over your head. Once you face south, hold the star chart over your head, and read it looking up, then east will be on your left and west will be on your right, just as depicted on your star chart.
• Remember that the real sky is much bigger than any star chart implies--even bigger than the planetarium sky might make you think. The constellation patterns shown on the chart will be spread out over a larger area in the real sky than you will expect. And there are many more stars in the real sky not shown on the chart!
• It is amazing how many simple patterns you can find all over the sky. When looking for patterns such as the Big Dipper, the W-shaped constellation Cassiopeia, or the Great Square of Pegasus you may find dippers, squares, w's and other familiar shapes in many places, and not just in the conventional asterisms and constellations you are looking for.
• If you want to face some direction other than south, turn the star chart so that the direction you are facing is in front of you.
• Can't read a star chart in the dark? Make a red flashlight and preserve your night vision.
• Want a star chart for every night? Get a planisphere. It works any time of night, any night of the year.
• Some related pages:
  • The bowl of night.
  • How constellations were named.
  • Constellation index.

Test your understanding

1. Given the star chart shown above, which of the scenes pictured below would you see along your eastern horizon?
2. Below is a star chart without the stars.
   
   1. The sun is setting on the west horizon. Draw a picture of the sun.
   2. The full moon is rising on the east horizon. Draw a picture of the moon.
   3. Imagine that a UFO appears directly over head. Draw a picture of a UFO at the point directly overhead (the zenith).
   4. Draw a star where Polaris, the north star, would appear.

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