Kemble's Cascade in the constellation Camelopardalis is a string of 8th magnitude stars that extend for a degree or more according to one account. If you look among the fainter stars in the sky you will frequently find four or more stars lined up in a row. The three belt stars in Orion (above) are a famous, bright example of three-star alignments, however, they are a good example of how projection effects and 'statistics' can create apparent strings out of stars that are found at very different distances from the Earth.
The majority of the alignments you see in the sky, no mater how impressively long, are likely to be of this kind because of the large number of stars in the sky, and the finite number of degrees over which they can be randomly distributed. There may, however, be a few alignments that are genuine because stars do form from the same cloud of gas, and if that cloud were elongated, there would be a preferred axis for the formation of the constituent stars. The problem is that any memory of this preferred axis will be lost very quickly because even these stars have motions relative to each other which in a few million years will tend to distort any initial alignment at birth, into a mostly random grouping. There is no known way to make persistent alignments of real star groups with a high degree of fidelity and coherence.
Enjoy the lucky few alignments you do find, compliments of the laws of chance operating in a very crowded galaxy! Ones involving more than 4 or 5 stars should be increasingly rare, and as for bright 10 star alignments, there may only be one of these in the whole sky!
Copyright 1997 Dr. Sten Odenwald
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