The start of radio astronomy started in the early thirties with a serendipitous discovery made by Karl Jansky, a radio engineer who worked for Bell Telephone Laboratories. He was studying the direction of arrival of thunderstorm static. In 1932 Jansky reported the first results of this study. He identified three types of static: i) static from local thunderstorms, ii) static from distant thunderstorms, always coming from the southern direction, and iii) as he described it "a steady hiss type static of unknown origin". The direction of the last type of static changed gradually during the day and had a period of 24 hours. Because there was a 24 hour cycle in the static pattern, Jansky speculated that this signal could not be made by a process on Earth, but might be associated with the Sun.
Further observations lead to the conclusion that the direction
of arrival of these waves was fixed is space, so he concluded that the waves
must come from outside the solar system. The coordinates that he found for
this radio source were 18 hours Right Ascension and degrees Declination,
with an error of less than 30 minutes in Right Ascension and 30 degrees in
Declination. Taking the error into account this was the position of the
centre of the Galaxy. The birth of radio astronomy was a fact.