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Starting With a BangIt has been 50 years since two scientists found landmark evidence for the Big Bang theory. Here are some little-known facts about the Big Bang theory and its champions.
Robert Wilson and Arno Penzias were using a large horn antenna at Bell Labs in New Jersey to gaze into the Milky Way. What they found, however, let them peer back 378,000 years after the Big Bang. The two scientists eventually found a cosmic fog that permeates the universe in every direction. Called the cosmic microwave background, it is a signature of the Big Bang that formed just after the universe began 13.8 billion years ago. [The Universe: From the Big Bang to Now in 10 Easy Steps]
But understanding what they found in 1964 was no easy task. Here are five odd facts you probably didn't know about the Big Bang theory and those who discovered it.
FIRST STOP: Pigeons Died
Two Pigeons Had to DieSlide 2 of 11
Two Pigeons Had to DieWhen Wilson and Penzias started using a horn antenna at Bell Labs, it registered higher-than-expected temperatures. At first, they thought pigeon droppings on the inside of the antenna caused the anomaly.
Wilson and Penzias cleaned out the antenna and sent the pigeons to a bird fancier, who released them. The pigeons then came back and started nesting inside the instrument again, and eventually, the birds were shot to keep them from continuing to nest in the antenna.
After ruling out pigeon poop as a possible cause for the higher-than-expected temperature, Wilson and Penzias landed on their landmark theory that the cosmic microwave background radiation, a remnant of the Big Bang, was actually causing the higher readings.
NEXT: No Eureka MomentSlide 3 of 11
No Eureka MomentSlide 4 of 11
No Eureka MomentWilson and Penzias never had the "Aha!" moment that many scientists experience when making a huge discovery, Wilson said. At first, they didn't take cosmology seriously because it hadn't produced any solid scientific results up to that point. But after meeting with other scientists, Penzias and Wilson were won over by the idea of the Big Bang.
"There was no 'aha' moment with this discovery. There was a long period of trying to get to the bottom of our problem," Wilson said here at the Harvard Smithsonian Center for Astrophysics on Feb. 20. "The importance of the discovery really only became clear over time. It became clear as theory was developed and as receivers got better so that one could look farther into the background and see something more than just a completely featureless picture."
NEXT: Entire Universe May Have Been HabitableSlide 5 of 11
Entire Universe May Have Been HabitableSlide 6 of 11
Entire Universe May Have Been HabitableThe entire early universe could have been one large habitable zone, some scientists say. At one point shortly after the explosive deaths of the first stars, life could have arisen in the "room temperature" universe, Harvard University astronomer Avi Loeb said. Some planets could have hosted microbial life forms just 15 million years after the Big Bang, a small amount of time in cosmic terms. [Alternatives to the Big Bang Theory Explained (Infographic)]
"My expectation is that this would be primitive life," Loeb said.
NEXT: Entire Universe May Have Been HabitableSlide 7 of 11
'Big Bang' Doesn't Necessarily Mean Universe's StartSlide 8 of 11