Reber could have performed his observations day or night, and in any kind of weather — but he found that automobile ignitions were giving off radio waves that were interfering with his signals. He ended up working with the telescope only late at night and during the early hours of the morning, when few people were driving. Even today, cars with spark plugs are kept away from radio telescopes.
Mapping the stars
Get to the root of it
Because it was small compared with the size of the radio waves it was trying to detect, Reber’s telescope had poor resolution — radio-wave sources near one another were picked up as one object. But Reber still managed to complete a radio map of our galaxy, the Milky Way. He published his work in 1942, but World War II started, and for several years no one had time to follow up.
Despite the delay it caused in the launch of radio astronomy, World War II advanced the development of radio telescopes. Radar, short for radio detection and ranging, was developed to detect enemy planes. It consisted of a transmitter to send out radio pulses and a detector to receive the pulses that were reflected back by an object. These radar techniques were applied to new radio telescopes to study astronomical objects once the war was over. Today’s home TV satellite dishes operate on the same principle as Reber’s radio telescope.
