The Development of Radio Astronomy 1 



By Gerald S. Hawkins 



Director, Boston University Observatory 

 Research Associate 

 Harvard College Observatory 



[With two plates] 



It is not often that we can witness the birth and development of a 

 new science such as radio astronomy. Most sciences have had 

 obscure beginnings, and the world has been slow to realize their im- 

 portance. Astronomy, for example, began with an interest in the 

 stars and the motion of planets long before the beginning of recorded 

 history, but this interest could not develop into a science until after 

 the invention of arabic numerals, which paved the way for the theo- 

 ries of planetary motion several hundred years later. The telescope 

 gave a great impetus to research when in 1609 Galileo discovered the 

 moons of Jupiter and Saturn's rings, but knowledge spread slowly 

 in those days and it took more than 200 years to establish the basic 

 facts of astronomy. We know that the sun is one star among 100 

 billion in the local galaxy, and in the universe there are probably more 

 than 100 billion other galaxies. With the additional techniques of 

 photography and spectroscopy rapid advances are being made in 

 all fields, so that we can study the atmosphere of the planets, the com- 

 position of the stars, and can investigate almost any problem we 

 choose. 



On the other hand, the science of radio astronomy has developed at 

 a time when the world seems to be almost at the peak of its technical 

 evolution. The radio sky was first glimpsed by Jansky in 1932. 

 Within 15 years the significance of the new science was realized and 

 then discovery followed discovery with bewildering speed. Radio 

 stars were found, some of which are quite invisible to the astronomer, 

 and others which are coincident with exploding stars and with gal- 

 axies in collision. Spiral arms have been mapped out in our local 



1 Reprinted by permission from American Scientist, vol. 45, No. 1, January 

 1957, copyrighted 1956 by the Society of the Sigma Xi. 



279 



451800—58 19 



