Ok, so the universe we live in is probably endless, and there are stars in every direction, and stars are really bright. So, why is it not permanent daylight all around us? Why space is dark?
It is a fascinating question “why space is dark? “. Well, fortunately, we have the answer to the question – why we’re not with shades all the time.
Well, that topic was first brought up by the German Astronomer Heinrich Wilhelm Olbers in the year 1823. It’s known as Olber’s Paradox, and it describes that if the universe is infinite, static, and timeless, then the night sky should be filled with those burning balls of fire. Apparently, though our night sky is more connect the dots than anything else.
Edwin Hubble figured out the paradox in 1929. He observed that everywhere he look in the cosmos, the spectrums of all the stars out there were a little red, meaning the light traveling from them was being stretched out, meaning the space itself light was going through was expanding.
For that reason, the universe isn’t static and there should be stars that are so far away that the light from them just hasn’t had time to come to us yet.
So, if we give it a million more years will we someday be able to tan at midnight?
Don’t hold too many hopes on that happening, because Hubble’s detection of universal expansion also means that the farther away an object is, the faster the space between it and us is expanding. After a huge enough length, space will be stretching out much quicker than light can fill the gap.
There’s another angle to the paradox though. Well, if the universe is all spreading away from everything else, it comes to mind that if you go far back enough, it was all bundled together in one place. This is where the theory of the big bang comes in. But if there was a bright instantaneous flash of existence that happened literally everywhere, shouldn’t we be able to observe that too?
Again, the riddle is solved by the rapid growth of space. In 1964 Arno Penzias and Robert Wilson were running a totally unrelated experiment with a radio telescope and they couldn’t get rid of this weird, unwanted static.
After checking that everything was functioning correctly, even sweeping the inside of the antennae for bird poop for hours, they found that the signal was originating from everywhere, and you can’t stop the broadcast. They finally ended up with the conclusion that the Cosmic Microwave Background Radiation should be the light from the big bang, but it had been stretched out after billions of years until it was low-energy microwaves that our eyes can’t observe.
So, there you have it. The universe makes sense again.
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