Page:Popular Science Monthly Volume 57.djvu/15

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5
THE COMING TOTAL ECLIPSE OF THE SUN.

makes it easier for those at the instruments to enjoy a more comfortable observing position than if it were nearer the zenith, where one must look directly upward. Of course, a storm of some kind may occur on that day to modify these general weather conditions and upset all calculations. While the cloud observations suggest that Georgia and Alabama have the best sites for the eclipse, it must be remembered that the duration is about one minute and twenty seconds in Alabama, and one minute and forty seconds in North Carolina. As a gain of twenty seconds in observing time will be considered by many of sufficient importance to take chances on the cloudiness, stations will be selected in North Carolina for that reason, although the probability for minimum cloudiness is

PSM V57 D015 Probable state of the track along the eclipse track.png
Chart II.—Probable State of the Sky along the Eclipse Track.
Average percentage of cloudiness in May and June.

twice as good in Georgia and Alabama. The table shows that the chances are only one to six against observers located in these States, while near the coast they are about two to six against them. On the whole, the general result is that observing in this region ought to be successful, because the favorable chances for good weather are above the average at that season of the year.

On Chart I there are six lines drawn across the track: No. 1 near New Orleans, and No. 6 on the ocean to the east of Norfolk, Va. These represent the places for which the times of the duration are computed in the American Nautical Almanac, with the following results:

 
No. h. m. h. m. m. s.
1. At 1 30 Greenwich M. T. = 7 27. Local M. T. the duration is 1 12.6
2. " 1 35  " " = 7 47.  " " " " "  1 19.6
3. " 1 40  " " = 8 05.  " " " " "  1 31.7
4. " 1 45  " " = 8 22.  " " " " "  1 31.7
5. " 1 50  " " = 8 40.  " " " " "  1 37.0
6. " 1 55  " " = 8 54.  " " " " "  1 41.9