What was the first colour of the universe?
Researchers have simulated the first visible colour that existed during the initial days of the universe and It's not the often visualised brilliant flash.
To give you a clue, the colour perceived by our eyes is based on its wavelength and frequency. X-rays, gamma rays, radio waves, and the faint cosmic microwave background are a few that are not visible to the naked eye.
Researchers have simulated the first visible colour that existed during the initial days of the universe. It's not the often visualised brilliant flash expanding from a point in darkness during the big bang.
Initially, temperatures were so high that light didn't exist. Even though there was light, no colour existed. It appeared after the nuclei and electrons cooled enough to bind into atoms. This process of cooling took around 380,000 years. It was a bright warm glow and appeared when the temperature of the earth was about 3,000 K.
This wavelength of the initial light is called a blackbody. The colour coming from it depends on the temperature, and when the first light came it had a bright orange-white glow, similar to the old 60-watt light bulb that might be present in your house. If we trace the exact colour it would be an orange glow similar to firelight.
The universe has cooled down to a very low temperature currently and the current colour coming out of the universe is described as a cosmic latte. It is similar to the pale tan of coffee.
The first stars began to appear after about 400 million years. As the stars and galaxies started appearing the universe started taking on a new colour.
The present colour of the universe is expected to die as the blue stars age and die. The remains like the deep red glow of dwarf stars will be the new colour of the cosmos. And if we go further to trillions of years from now, all the light will fade and the universe will be a sea of black.