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Take the most compressed galactic cluster that you can imagine and add some more stars. Keep on adding stars until it is impossible to separate one from another, and you have created a globular cluster. A typical globular cluster contains 100,000 individual stars and some contain over 1,000,000 stars.
The incredible concentration of stars, especially in the central core of a globular cluster creates a white patch in the sky. Only in the thinned-out area of the periphery is it possible to see individual stars. Depending on the acuity of your vision and the quality of your binoculars, the central core will be solid white or have a grainy appearance. The core may be sharply defined or gradually fade away. Globular clusters tend to be spherical and so appear to us as circles, although some have slightly irregular forms.
After seeing hundreds of thousands of stars compressed into small spot in the sky from afar, it is difficult not to attempt to imagine what the sky appears like from somewhere in the middle of a condensed cluster. The density of stars in the center of a globular cluster is 1,000 times as great as in the area of space surrounding our Sun. According to Stanley P. Wyatt, on the average the nearest neighboring star within such a cluster is a tenth of the distance of the closest star to the Sun:
From the definition of apparent magnitude, we know that it [the neighboring star] is brighter by 5 magnitudes. Your alpha Centauri is now brighter than Venus seen from Earth. What is sixth magnitude on Earth is first magnitude for you. Your sky is speckled with 10,000 stars that are brighter than Sirius and with myriads of fainter ones – a spectacular view indeed.
Examples: M4, M13