When you look up at the night sky, you are overwhelmed with the confidence that space is an endless sea of darkness. What color is the universe ?! Yes, of course, black! A predictable answer, but it is not entirely correct, or rather, completely incorrect. To begin with, it is important to understand that there is actually no black color as such. This is confirmed by Ivan Baldry, professor at the Liverpool Institute for Astrophysical Research at John Moore University in the UK:
Black is not a color. Black is simply the absence of visible light.
Baldry emphasizes that color is the result of the activity of visible light, which is created in space by stars and galaxies. Together with Karl Glazebrook, a distinguished professor at the Center for Astrophysics and Supercomputers at Swinburne University of Technology in Australia, Baldry back in 2002 defined the concept of the cosmic spectrum, which is the color of the universe. To do this, they measured the light from tens of thousands of galaxies and, let’s say, averaged it.
The cosmic spectrum is the color of our universe.
Stars and galaxies emit electromagnetic radiation, which differs depending on the wavelength. The entire spectrum of light that comes from celestial bodies can be divided into several groups from the shortest to the longest:
- gamma rays;
- X-rays;
- ultraviolet light;
- human visible light;
- infrared radiation;
- microwave;
- radio waves.
Curiously, the visible light that the human eye can discern is only a tiny fraction of the entire electromagnetic spectrum. Yes, everything that a person perceives as color is just different wavelengths of visible light. What we call red and orange are longer waves. But blue or, for example, purple colors are short wavelengths.
According to Baldry, the visible spectrum of stars and galaxies is a measure of the average brightness and wavelengths of light they emit. In 2002, The 2dF Galaxy Redshift Survey was surveyed at the Siding Spring Observatory in Australia to create a three-dimensional map of the universe. The efforts of the Baldry and Glazebrook team in this survey also made it possible to capture the visible spectrum of more than 200,000 galaxies and determine the average color of the Universe. Actually, Baldry and Glazebrook called it the Cosmic Spectrum, which …
… is the sum of all the energy in the universe, emitted at different optical wavelengths of light.
The human eye cannot see the cosmic spectrum
In order for a person to see the cosmic spectrum, it must be processed in a special way using special software. The thing is that three types of special light-sensitive cones are used in the structure of our eye, each of which helps to perceive an individual range of visible light waves. On the one hand, we have blind spots. On the other hand, our perception of color is highly dependent on external conditions.
In 1931, the International Commission on Illumination adopted the CIE color space, which aims to compensate for the visual limitations of the human eye. It assigns colors to different wavelengths that the average observer can see. Armed with this system, Baldry and Glazebrook determined that the average color of the universe is beige, and it is not that far from white… Yes, as it turned out, space is not black, as many ordinary people believed – its color is diametrically opposite.
Some may think that the discovery is relatively boring. Moreover, for scientists it was quite predictable, because white is the result of combining all the lengths of visible light, and the cosmic spectrum includes a really wide range of waves. To make it easier for ordinary people to understand the cosmic color, it was decided to come up with a name for it. Primitive Clam Soup, Beige Big Bang and “Space Latte” eventually settled on the latter.
The color of the entire universe cannot be seen while on Earth
Yes, it is very important to understand that the concept of cosmic color represents the original shade of the universe, and not the one that can be seen today from our planet. Bulrdi and Glazebrook insist that the cosmic spectrum is what one would be able to observe if one were able to reduce the universe to the size of a conventional coffee table and look at it from above. And there is a fairly simple explanation for this.
The fact is that due to the Doppler effect, light can propagate over great distances. During this, its waves inevitably stretch, systematically approaching the red spectrum of light, which astrophysicists call redshift. This fact underlines the fact that it is impossible to observe the color of the cosmos from the Earth exactly in the form that the celestial bodies originally emitted. Thus, in Baldry’s words:
Cosmic latte is a color that we could perceive if we could look at the Universe from above and see all the light emanating from each galaxy, stars and gas clouds at the same time.
Source: Space.
Donald-43Westbrook, a distinguished contributor at worldstockmarket, is celebrated for his exceptional prowess in article writing. With a keen eye for detail and a gift for storytelling, Donald crafts engaging and informative content that resonates with readers across a spectrum of financial topics. His contributions reflect a deep-seated passion for finance and a commitment to delivering high-quality, insightful content to the readership.
