To locate the Northern Crown, find Arcturus and Vega, the two brightest stars in the northern hemisphere. Draw a straight line between them and you will find not only the mighty Hercules , but the splendid Corona Borealis. The size of each star indicates its relative magnitude . Constellation names are light blue . Messier object numbers are pink .
Globular clusters are gold starbursts .
Open clusters are dotted white circles. Planetary nebula are green diamonds . Bright nebula are magenta squares . Dark nebula are grey rectangles . Green x's are x-ray sources.