The Life of a Star

by Paul Curzon, Queen Mary University of London

The first computers transformed the way research is done. One of the very first computers, EDSAC, contributed to the work of three Nobel prize winners: in Physics, Chemistry and Medicine. Astronomer, Joyce Wheeler was an early researcher to make use of the potential of computers to aid the study of other subjects in this way. She was a Cambridge PhD student in 1954 investigating the nuclear reactions that keep stars burning. This involved doing lots of calculations to work out the changing behaviour and composition of the star. Joyce had seen EDSAC on a visit to the university before starting her PhD, and learnt to program it from its basic programming manual so that she could get it to do the calculations she needed. She would program by day and let EDSAC number crunch using her programs every Friday night, leaving her to work on the results in the morning, and then start the programming for the following week's run. EDSAC not only allowed her to do calculations accurately that would otherwise have been impossible, it also meant she could run calculations over and over, tweaking what was done, refining the accuracy of the results, and checking the equations quickly with sample numbers. As a result EDSAC helped her to estimate the age of stars.