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Next to Hercules and standing on Scorpio, you will find the large constellation of Ophiuchus. The brightest star of Ophiuchus has only a magnitude of about 2 but you can see the constellation that looks a bit like a misshapen triangle under less than ideal conditions.
Ophiuchus contains to Messier objects - M10 and M12 - which are both globular clusters of stars. Since Messier, there have been many other sky catalogues. At right ascension 18 hours 28 minutes, declination 6 degrees 30 minutes (the upper left hand corner of the constellation chart) there is an open cluster of stars that is labeled 6633. This is a number in a later catalogue called the "New General Catalogue" which was compiled in 1888. An open cluster consists of a large number of stars, although it not as densely populated as a globular cluster. This object is usually referred to as NGC6633 although on the SkyTour charts NGC objects are indicated simply by 4 digits numbers.
Scorpio