Many of the great discoveries of science came only after extensive research, rigorous calculations and laboratory-controlled procedures. Part of them, however, is the result of a combination of errors, accidents and accidents – the Big Bang theory is an example.
The origin of the Universe was discovered in a place where no one sought. And it was formulated thanks to an earlier fortuitous discovery – that gave rise to radio astronomy, a branch of astronomy that studies the electromagnetic radiations emitted or reflected by the celestial bodies.
“In the 1930s, Bell Labs were trying to create radiotelephones, but there was a signal that was interfering with the transmissions across the Atlantic. They asked Karl Jansky (physicist and radio engineer) to investigate,” Sara Bridle, a professor of astrophysics at the University of Manchester.
“Jansky designed a special radio receiver to pick up radio waves in all directions. It was called a ‘Jansky’s carousel’ because it rotated to find the places where those waves came from,” says Bridle.
“Eventually, Jansky realized that they came from the constellation Sagittarius, which is where we now know the centre of the Milky Way is,” the teacher adds.
She explains that this was the first record of radio waves coming from outside the Earth and the Solar System – and the beginning of radio astronomy, which opened a whole new window for man to explore the Universe.
“It was pure chance, and it was not even an astronomer,” adds astrophysicist Sara Bridle.
The discovery was important because it revealed a whole piece of the Universe that was still completely invisible and therefore unknown.
For the astronomer Nial Tanvir, it was like being in a dimly lit room, watching all that could be seen in awe, and suddenly someone comes in with night-vision goggles.
“If we go beyond the limits of what we see with our eyes, we have the infrared, the microwave, radio waves and, in another direction, X-rays and Y. If we use these other types of light than those we see with our eyes, “explains Tanvir.
The origin of the Universe is par excellence one of these processes – proven by chance, which helped empirically demonstrate the so-called Big Bang.
“The idea of the Big Bang from a theoretical point of view is that at one time in the past, all matter and all the energy of the Universe was one place and then exploded. This explosion marked the beginning of time and the expansion of space, starting from nowhere, and the expansion continues, “summarizes Tanvir. “It sounds like a crazy theory, but it’s what math tells us,” the astronomer adds.
The Great Explosion theory gained momentum during the last century. However, until the mid-1960s, compelling evidence was still lacking to overturn alternative theories.
The missing evidence came to light thanks to the cosmic microwave background radiation (CMB), another chance.
“The discovery of CMB was made by people who were not even looking for (the origin of the Universe),” says professor of astrophysics Sara Bridle.
all started with Arno Penzias and Robert Woodrow Wilson were working with a supersensitive antenna – design worthy of science fiction film (see picture below) – designed to detect the radio waves emitted by echo balloon satellites, balloon satellites.
Penzias and Wilson used this antenna to detect radio waves when they encountered a strange noise (Photo: Nasa) Penzias and Wilson used this antenna to detect radio waves when they encountered a strange noise.
Penzias and Wilson used this antenna to detect radio waves when they encountered a strange noise (Photo: Nasa)
To measure the waves, they needed to eliminate all kinds of interference that came from other sources.
As they did so, the researchers came upon an unknown and persistent noise, “a weak but easily detectable signal that came from nothing on Earth or the Solar System, not even from our galaxy,” says Tanvir, recalling the story.
This signal came from all directions.
An uncomfortable noise
Everywhere they found the same “background heat,” as Penzias himself explained in an interview with the BBC in the late 1970s, referring to the energy emitted by the waves.
“Instead of getting a beautiful, flawless zero that we were expecting for the Milky Way, we got a result that was 100 times higher than expected: a temperature of almost four degrees,” he said. Penzias.
“And those four grades were the result after all the ‘contributions’ of soil, atmosphere and antenna had been subtracted,” he said.
In search of an explanation for what was happening, they considered various possibilities, among them some unusual ideas.
“The biggest suspicion came from some pigeons visiting the antenna – we always had to clean up the ‘traces’ they left,” he said, referring to bird faeces.
Eventually, “the pigeons were captured and sent to a distant place”. But the animals came back and “telling what we did with them is probably not politically correct,” said the scientist.
What’s behind the explosion
Although they were gone with the pigeons, the annoying sound did not disappear. They had not yet connected the noise to the Big Bang – but who would think about it anyway?
“They were really confused and by chance, a friend commented that there was a group of theoretical physicists who was right there just trying to decipher what had happened after the Big Bang,” says Bridle.
“In theory, one would expect that there would be much light left by the Big Bang explosion, a light that would be present today,” says the teacher. “So they called the physicists and realized that what they had found was exactly the kind of signal that that explosion would send.”
They had found the basis of modern cosmology.
An effort to improve radio communications, a noise in space and some theoretical physicists nearby … all came together in a remarkable accident that, according to most scientists, gave the world what was needed to prove the greatest of all theories: the Big Bang.
One could say that Penzias and Wilson won the scientific lottery.
Once the pigeon’s poop was discarded, the annoying “noise” turned out to be the accidental discovery of the century, evidence of the origin of the Universe.
But although the discovery of CMB, cosmic microwave background radiation, was an accident, is it really possible to say that it was pure luck?
Penzias and Wilson were lucky enough to come across the noise and find the theory to explain it literally right next to it. The duo, however, was very careful and did not ignore the evidence that appeared to them, no matter how annoying they were.
In a world where access time to telescopes is regulated and the test of hypotheses, the basis of the scientific method, depends on funding, modern radio astronomy has learned from the accidents of its past.
“Now, when a new telescope is made, we ensure that new types of observations can be made so that we do not just try to solve known unknowns,” says Sarah Brittle.
In other words, the door must always be open to chance and chance.