Generalities: it is a big constellation of the northern sky, not very bright, but including very interesting objects. It transits at midnight in July.

Origins and mythology: it is devoted to Hercules,  the hero of the twelve labours.

Stars: it includes 2 stars under  magnitude 3 and other 13 under  magnitude 4. The brightest is beta, an orange star named Kornephoros, of magnitude 2.77, followed by zeta , of magnitude 2.81 and yellow color (Rutilicus).

Table of stars brighter than magnitude 3.5
 

Star	Proper name	Magnitude	Spectrum	Colour	Distance (light-years)	Notes
Beta	Kornephoros	2.77	G8	arancio	101
Zeta	Rutilicus	2.81	G0	giallo	31
Alpha	Ras Algethi	3.00 (variabile max)	M5	rosso	218
Delta	Sarin	3.14	A3	bianco	91
Pi		3.16	K3	arancio	390
Mu		3.42	G5	giallo	26

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Other objects: it contains the nicest globular cluster of the northern sky, M13. It is a cluster made up of half a million stars and  25,000 light-years far. It can already be observed with common binoculars. In Hercules there is also another globular cluster, more modest but interesting, M92.

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