324 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1963 



200 miles on the sun, and several light years in the nearest stellar 

 systems such as the spiral Andromeda Nebula. Clearly, even our best 

 photographs have been coarse indeed. 



The astronomical profession had adjusted itself through the cen- 

 turies to labor under this all-prevailing handicap. Then, about a 

 decade ago new technical tools appeared which promised to remove 

 this handicap for good : Eockets began to lift above the earth's atmos- 

 phere small telescopes with which for a few short minutes the ultra- 

 violet light of the sun and the stars could be studied ; balloons carried 

 astronomical cameras above 95 percent of the atmosphere and brought 

 down for the first time sharper photographs of astronomical objects ; 

 now satellites are being developed which will carry major astronom- 

 ical instruments far above the earth's atmosphere and may permit 

 effective research there for long time intervals. 



It is hard to describe the force of the impact that this development 

 has had on astronomy as a science and on astronomers as persons. 

 Even now astronomers are far from having reached a balanced adjust- 

 ment to the new circumstances ; we are still swaying back and forth 

 between elation and bewilderment. Nevertheless, I think it is by 

 now obvious that the new tools of rockets, balloons, and satellites open 

 up an immense area for astronomical research, though it would be 

 clearly a grave mistake to consider these new tools actually as replace- 

 ments for the old ground-based instruments and techniques, rather 

 than as decisive and stimulating additions. 



If, from here on, I concentrate entirely on one specific astronomical 

 balloon project — Project Stratoscope — my sole reason is that I am 

 very closely acquainted with this activity. Project Stratoscope is 

 only a minute facet in the entire program of off-the-ground astro- 

 nomical and geophysical research. However small in the overall re- 

 search picture, for those of us involved it has been and continues to 

 be an absorbing and immensely exciting activity. 



Project Stratoscope arose from a specific scientific problem. The 

 tremendous energies produced by hydrogen burning in the interior of 

 the sun are carried out to the surface by enormous convective move- 

 ments of the gases in the outer layers of the sim. These convective 

 movements can actually be seen on the surface of the sun in the form 

 of the granulation, the fine mottled structure covering the entire solar 

 surface at all times. It became clear that to understand the detailed 

 mechanism by which this convective motion of the gases transports the 

 heat energies outward is an unavoidable prerequisite to following the 

 evolutionary changes of any star such as the sun. On the other hand, 

 it became desperately clear that, though the detailed observational 

 study of the solar granulation would help much toward this under- 

 standing, such detailed observations on the ground were made essen- 

 tially impossible because of the image deterioration caused by the 



