Category: arno penzias

Ask Ethan: Was The Critical Evidence For The Big Bang Discovered By Accident?

“The cosmic microwave background is a landmark evidence of the Big Bang origin of the universe. How come this discovery is labelled as an accidental one?”

Imagine that you lived in a world where nobody knew where the Universe came from. Sure, different theories led to a myriad of possibilities, but it takes observations to decide what’s correct in this Universe. In the 1920s, Georges Lemaitre worked out the first early details of the Universe originating from a hot, dense state. In the 1940s, George Gamow and his collaborators started to pull out robust predictions, like the nuclear predictions for fusion in the early Universe, the growth of stars, galaxies and clusters in the Universe, and the existence and rudimentary properties of a leftover glow: today’s Cosmic Microwave Background. Yet the actual discovery of this leftover radiation from the Big Bang, despite the meticulous planning of a group working to detect it explicitly, truly was a serendipitous accident. 

You’ll never look at the expression “one astronomer’s noise is another astronomer’s data” the same way again!