APPENDIX 8 
REPORT ON THE ASTROPHYSICAL OBSERVATORY 
Sir: I have the honor to submit the following report on the activi- 
ties of the Astrophysical Observatory, including the Division of As- 
trophysical Research and the Division of Radiation and Organisms, 
for the fiscal year ended June 30, 1944: 
DIVISION OF ASTROPHYSICAL RESEARCH 
No male assistants could be retained at the three solar-constant ob- 
serving stations, Montezuma, Chile, Table Mountain, Calif., and Ty- 
rone, N. Mex., on account of war conditions. In this situation the 
wives of the three field directors, Greeley, Warner, and Moore, have 
stepped into the breach and are assisting with observing and comput- 
ing. It has therefore been possible to keep the three stations in opera- 
tion in this exceptionally interesting period. 
As pointed out in last year’s report, the predicted march of solar 
variation through 1945 indicates a large depression of solar radiation 
beginning in October 1944, comparable to that which occurred 23 
years earlier, beginning in 1921. Figure 1 shows that the observations 
made at Montezuma observatory up to the middle of the year 1943 
support thus far the trend of the prediction published in figure 14 of 
volume 6 of the Annals of the Astrophysical Observatory. It is there- 
fore confidently expected that the depression of the solar constant 
will begin with October 1944. It is not yet possible to forecast what 
exact effects this depression (similar to that of 23 years ago) may 
produce in weather, but as stated in an article a generation ago by 
Abbot,’ unusual weather conditions may be anticipated. 
Most of the time of Mr. Hoover, Mrs. Bond, and Miss Simpson at 
Washington, and part of that of Mr. Aldrich has been occupied with 
the reduction and determining of the statistical corrections for the 
solar-constant work of the three observing stations since 1939. Ad- 
ditional types of observing, namely, polarization of the sky, and energy 
spectrum observations limited to the ultraviolet region, have accumula- 
ted in these recent years. Their bearing on the determination of the 
solar variation is of great interest. 
Mr. Aldrich has been largely occupied with special secret war 
problems, and part of Dr. Abbot’s time has been thus spent also. 
1 Proc. Nat. Acad. Sci., vol. 9, No. 6, pp. 194-198, June 1923. 
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