The entire known Universe in one image (1 Viewer)

[Laron]

Here is a image depicting the entire known Universe. It's an illustrated logarithmic scale conception of the observable Universe with the Solar System at the center. It's created by musician and artist Pablo Carlos Budassi, based on logarithmic maps put together by Princeton University researchers, as well as images produced by NASA from observations made by their telescopes and roving spacecraft.

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The higher resolution version is here:
https://upload.wikimedia.org/wikipedia/commons/e/e7/Observable_universe_logarithmic_illustration.png

 

[Snowmelt]

But why is space dark? I think it is a very colourful place. Answering my own question:

StarChild Question of the Month for December 2002
Question:
Why is space black?

Answer:
Your question, which seems simple, is actually very difficult to answer! It is a question that many scientists pondered for many centuries - including Johannes Kepler, Edmond Halley , and German physician-astronomer Wilhelm Olbers.

There are two things to think about here. Let's take the easy one first and ask "why is the daytime sky blue here on Earth?" That is a question we can answer. The daytime sky is blue because light from the nearby Sun hits molecules in the Earth's atmosphere and scatters off in all directions. The blue color of the sky is a result of this scattering process. At night, when that part of Earth is facing away from the Sun, space looks black because there is no nearby bright source of light, like the Sun, to be scattered. If you were on the Moon, which has no atmosphere, the sky would be black both night and day. You can see this in photographs taken during the Apollo Moon landings.

So, now on to the harder part - if the universe is full of stars, why doesn't the light from all of them add up to make the whole sky bright all the time? It turns out that if the universe was infinitely large and infinitely old, then we would expect the night sky to be bright from the light of all those stars. Every direction you looked in space you would be looking at a star. Yet we know from experience that space is black! This paradox is known as Olbers' Paradox. It is a paradox because of the apparent contradiction between our expectation that the night sky be bright and our experience that it is black.

Many different explanations have been put forward to resolve Olbers' Paradox. The best solution at present is that the universe is not infinitely old; it is somewhere around 15 billion years old. That means we can only see objects as far away as the distance light can travel in 15 billion years. The light from stars farther away than that has not yet had time to reach us and so can't contribute to making the sky bright.

Another reason that the sky may not be bright with the visible light of all the stars is because when a source of light is moving away from you, the wavelength of that light is made longer (which for light means more red.) This means that the light from stars that are moving away from us will become shifted towards red, and may shift so far that it is no longer visible at all. (Note: You hear the same effect when an ambulance passes you, and the pitch of the siren gets lower as the ambulance travels away from you; this effect is called the Doppler Effect).

https://starchild.gsfc.nasa.gov/docs/StarChild/questions/question52.html

 

[CosmicReflections]

Sometimes, two additional colors can be seen in the rainbow. After the red comes a bright brown and after the violet comes a bright forest green. On and on...as the soul activates new functions in the physical brain, what looks black will be an explosion of bright frequencies translated into beautiful colors. We just have to be ready to see the true colors, in what the limited brain cannot translate and therefore is left as a gap of pitch black.

 

[Laron]

But why is space dark?

I wonder if Siri would know.

 

[Laron]

In relation to my OP, here is a wikipedia definition of what it means when you hear "entire known universe" or "observable universe"

The observable universe is a spherical region of the Universe comprising all matter that can be observed from Earth at the present time, because electromagnetic radiation from these objects has had time to reach Earth since the beginning of the cosmological expansion. There are at least 2 trillion galaxies in the observable universe,[7][8] containing more stars than all the grains of sand on planet Earth.[9][10][11] Assuming the Universe is isotropic, the distance to the edge of the observable universe is roughly the same in every direction. That is, the observable universe is a spherical volume (a ball) centered on the observer. Every location in the Universe has its own observable universe, which may or may not overlap with the one centered on Earth.​