After determining which constellation to observe, you will match your nighttime sky with one of the magnitude charts of that constellation. This will determine the magnitude of the faintest stars that you can see at your location. (Magnitude Charts are included in the printable Activity Guide.) You might see more stars or fewer in different locations, depending on how much light pollution is in your area.
Northern Hemisphere (Cygnus) Magnitude Charts - Practice with a fun quiz!
Southern Hemisphere (Sagittarius) Magnitude Charts - Practice with a fun quiz!
Astronomers use a special term to talk about the brightness of stars. The term is "magnitude." The magnitude scale was invented by the ancient Greeks around 150 B.C. The Greeks put the stars they could see into six groups. They put the brightest stars into group 1, and called them magnitude 1 stars. Stars that they could barely see were put into group 6. So, in the magnitude scale, bright stars have lower numbers. Read more about the magnitude of stars at Windows to the Universe.
