Annual report of the Board of Regents of the Smithsonian Institution . y, we con-centrated attention on this one feature of the distribution by dealingwith the average of the counts in all longitudes. This eliminated anyinfluence arising from the possible progressive change with longitudein which we are now interested. And now we avoid any disturbancewhich might arise from the crowding toward the Milky Way by com-paring only counts of stars in the same latitude, and, of course, to thesame limit of brightness. A simple procedure is to compare, for agiven latitude, the number of stars actually c
Annual report of the Board of Regents of the Smithsonian Institution . y, we con-centrated attention on this one feature of the distribution by dealingwith the average of the counts in all longitudes. This eliminated anyinfluence arising from the possible progressive change with longitudein which we are now interested. And now we avoid any disturbancewhich might arise from the crowding toward the Milky Way by com-paring only counts of stars in the same latitude, and, of course, to thesame limit of brightness. A simple procedure is to compare, for agiven latitude, the number of stars actually counted in each regionwith the average number for the whole circuit of the sky, and thento see whether the differences show any progressive , to test the results we may make independent comparisons forseveral different latitudes and for a number of limits of brightness. Figure 1 illustrates the results for the stars brighter than the six-teenth magnitude, in general for every 10° up to latitude 70° on either COUNTING THE STARS—SEARES 193 360 + 70. Figure l .—Deviations of the observed numbers of stars in different parts of the sky from the average numbersshown in Table I. The stars here considered are brighter than magnitude ; the general similarity inthe curves for all galactic latitudes (figures on the left), with low points around longitudes 120° to 160°(figures at top), and high points around 300° to 350°, indicates that the center of the system of these starsis in longitude 319° 194 ANNUAL EEPORT SMITHSONIAN INSTITUTION, 192 9 side of the Milky Way. Similar diagrams, showing very similar curves,were also prepared for limiting magnitudes 9. 0, , , and along the Milky Way, or along one of the parallel circlesidentified by the galactic latitudes on the left of the diagram, are indi-cated by longitudes at the top, measured from a standard meridian,just as in the case of longitudes on the earth. Portions of curves whichlie a
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