“Early this year astronomers discovered that five celestial objects, previously regarded as being faint and somewhat unusual stars in our galaxy, are perhaps not faint stars at all. They are extremely powerful sources of radio noise and, according to new estimates of their light output, are perhaps the brightest objects in the universe. Astronomers provided precise positions of five radio sources, which were then identified with starlike objects on photographic plates made at the Mount Wilson and Palomar Observatories. In recognition of their small size, and for lack of a better name, they are called quasi-stellar radio sources.”

Scientific American, December 1963

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