Look up at the night sky with your own eyes or marvel at images of the universe online, and you’ll see the same thing: the inky, unfathomable blackness of space interrupted by dazzling stars, planets, or spacecraft. It’s black for a reason, however. Why isn’t space as beautiful as the blue sky during the daytime?
Unexpectedly, the explanation has nothing to do with a lack of illumination.
Astronomy and astrophysics graduate student Tenley Hutchinson-Smith say that “you would think that since there are billions of stars in our galaxy, billions of galaxies in the universe and other objects like planets that reflect light,” when we look up at the sky at night, it would be extremely bright.” It’s a lot darker than it seems.”
“Because our universe is expanding faster than the speed of light… the light from distant galaxies might be stretching and turning into infrared waves, microwaves, and radio waves,” Hutchinson-Smith said. This contradiction, known as Olbers’ paradox in the physics and astronomy circles, can be explained by the theory of space-time expansion. They look black (dark) because they are undetected by the human eye.
There is no doubt that Miranda Apfel and Hutchinson-Smith are on the right track. Stars emit light in all hues, including those invisible to the human eye, including ultraviolet and infrared. If humanity could see microwaves, “all of space would be illuminated.” According to Apfel’s theory, there are still protons and electrons in the cosmos that spread the light energy from the Big Bang, and it still fills all of space.
Because space is a near-perfect vacuum, interstellar and interplanetary space appear black. Remember that the blue color of Earth’s sky comes from the sun’s blue and violet wavelengths being scattered widely by the atmosphere’s molecules, including nitrogen and oxygen. Although light travels in a straight path when the matter is absent, this doesn’t hold in the absence of matter. To our sight, the space between the stars and planets is an almost perfect vacuum, which means that there are very few particles in it. In the absence of light, the eyes only perceive darkness.
It should be noted that according to a 2021 report published by the journal The Astrophysical Journal, space may not be entirely black as scientists had previously believed. NASA’s New Horizons mission to Pluto and the Kuiper Belt has allowed researchers to observe space without light pollution from the Earth or the sun. All light from known stars, our Milky Way, and other galaxies and any light that could have slipped in due to camera quirks were removed from the scientists’ photographs collected by the spacecraft. They discovered that the universe’s background light was still twice as brilliant as they had previously expected.
There are no known explanations for why the brightness has increased; thus, future research will concentrate on this area of inquiry. As of right now, the only thing that is certain about space is that it might be more “charcoal” than pitch-black.