A Very Brief History of Radio Astronomy

 

The original radio astronomer was a machinist in Chicago without academic credentials.  The following is my theory about how he came to be recognized.

 

As a young man of 19 in India Chandresekhar attended a lecture by James Eddington, who was giving a series of lectures on astronomy in India just after World War I.  The young man introduced himself after the lecture and asked some searching and perhaps unanswered questions.  Eddington asked for his name and address and after returning to England sent him a scholarship to Cambridge University.  On route to England by steamship Chandresekhar did some “back of the envelope” calculations (Gettysburg address quality as it turned out).  He came up with 1.44 solar masses as the mass of a star which, having consumed all its hydrogen fuel, would be massive enough to collapse by gravity to what amounts to a giant atomic nucleus with a specific gravity of about 100,000 times that of water (1/4 teaspoon would weigh 50 tons).

 

These were totally innovative concepts.  Eddington himself scarcely understood the math and wasn’t very interested, but some of Eddington’s younger colleagues encouraged Chandresekhar to pursue the ideas and arranged for their publication.  Decades later neutron stars with enormous densities were actually discovered.  None of them weighed less than 1.44 solar masses.  Chandresekhar got a Nobel Prize.

 

After World War II when wartime radar research was declassified including the incidental discovery of sources of radio waves from outer space, a machinist in Chicago read about radio waves from outer space in the daily newspaper and built the world’s first radio telescope in his backyard.  Chandresekhar had long since moved from England and was an established astrophysicist at the University of Chicago.  When he got wind of this machinist and his backyard telescope, he sent some graduate students to check it out.  They found that amazingly the machinist had a stearable directional radio receiver.  With his he had determined the location in the sky among the constellations of several of these radio sources.  He even had the locations plotted in standard astronomer’s nomenclature of declination and right ascension (the astronomical equivalents of latitude and longitude).

 

Chandresekhar arranged for some grant money for the machinist and recognition for his accomplishment.  I like to think that Chandresekhar personal experiences as a young man motivated him to treat the machinist as a colleague.

 

Perhaps you have heard of the orbiting x-ray telescope, Chandra.  This happens to have been Chandresekhar’s nickname among his peers, a very fitting honor to a remarkable human being.  Writing this was quite an emotional experience for me, perhaps because I aspired to be an astrophysicist as a high school student.

 

 

June 8, 2002

John A. Frantz, M.D.