In the early 1940s Cygnus A was identified as the most powerful radio source in the Cygnus constellation, but until 1951 the objectΓÇÖs position in the sky was too poorly known to allow study of it with optical telescopes. At that time, F. Graham Smith of Cambridge University studied the object and located it more precisely. He sent the coordinates to Walter Baade, who had access to the largest telescope in the world, the 200 inch at Palomar Observatory. BaadeΓÇÖs two photographs of Cyg A (one in blue and one in yellow light) showed numerous galaxies.
Baade hoped Cygnus A would finally provide the evidence he needed for his colliding galaxy theory (Cyg A appeared to consist of two components). A year before, he
