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Today the most accepted theory of the origin of the universe is the so-called Big-Bang, according to which from an infinitely small point but with infinite mass, all the matter and energy present in the universe arose after an incredible explosion.
George Gamow, a Russian-American scientist born in 1904, predicted that, if so, the Big Bang should have left an imprint of the outbreak that, after all these billions of years, should be detectable in the microwave.
In 1965, American scientists Arno Penzias and Robert Wilson were working on a new type of antenna to listen to the universe and found a signal from all over the universe that interfered with their investigations.
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After reviewing the entire installation and even cleaning all the bird droppings in case its dielectric nature could interfere, they concluded that this signal had to be the background radiation predicted by Gamow, which earned them the Nobel Prize in 1978.
In order to confirm this theory, the COBE satellite (COsmic Backgroun Explorer) was launched, which for 5 years (1989-1993) scanned the universe until obtaining the first of these cosmic radiation maps.
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As the resolution was not very good, in 2001 a second satellite called WMAP (Wilkinson Microwave Anisotropy Probe) was launched, which left us this picture of the universe when it was only 380,000 years old.
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It was around this time that the universe cooled down enough for the particle soup to form the first atoms, which made the universe transparent and allowed light to travel through space to this day.
In this photograph, the small lumps of yellow and red colors represent warmer and denser areas of the early universe, from which galaxies that we can see today in the sky would eventually emerge.
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