Annual report of the Board of Regents of the Smithsonian Institution . ults foundfrom the Mount Wilson counts, and some by other observers fromother data, plotted to show the changes in the direction of the center(L) and in the position of the secondary galaxy (p, tilt of plane;Lo, direction of tilt). These calculations afford opportunity for a closer comparisonof the numbers of stars on opposite sides of the Milky Way. Ex- COUNTING THE STARS SEAEES 197 pressed as a ratio of the numbers on the north side to the numbers onthe south, the results run as follows: Limiting magnitude Ratio, north to
Annual report of the Board of Regents of the Smithsonian Institution . ults foundfrom the Mount Wilson counts, and some by other observers fromother data, plotted to show the changes in the direction of the center(L) and in the position of the secondary galaxy (p, tilt of plane;Lo, direction of tilt). These calculations afford opportunity for a closer comparisonof the numbers of stars on opposite sides of the Milky Way. Ex- COUNTING THE STARS SEAEES 197 pressed as a ratio of the numbers on the north side to the numbers onthe south, the results run as follows: Limiting magnitude Ratio, north to south 13. 5 16. 0 0. 67 0. 75 0. 77 0. 98 1. 01 Here again is a change with limiting brightness. Counting onlyto the ninth magnitude, we find 50 per cent more stars in the southernhalf of the sky than in the northern. As fainter stars are added, theexcess decreases and disappears near the sixteenth there on the numbers in the two halves of the sky are sensiblyequal. Moreover, the ratios for individual zones in equal latitudes, 4- Mag fe. 150 Figure 2.—L is the longitude of the center of the stellar system as derived from stars brighter thanvarious limits of magnitude; p and Lo are the tilt with respect to the Milky Way, and the directionof the tilt of the circles (secondary galaxy) about which the stars are symmetrically situated andtoward which they tend to crowd north and south, show a similar sequence of values; hence, althoughthe distribution of bright stars in latitude is notably asymmetrical,that of faint stars is very symmetrical. THE LOCAL SYSTEM The probable explanation of these changes with magnitude issuggested by following the curves of Figure 2 back to about the sixthmagnitude, for there we come to figures with which we are familiar inanother connection. Immediately surrounding us in space is a large 198 ANNUAL EEPORT SMITHSONIAN INSTITUTION, 19 2 9 collection of very hot, massive stars, mostly brighter than the sixthmagnitude, havin
Size: 1827px × 1368px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorsmithsonianinstitutio, bookcentury1800, bookdecade1840
