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  • Ok so the universe is probably infinite, and there’s stars in every direction, and stars

  • are super bright. so why isn’t it basically daylight all the time?

  • Hey there my bright spots, Julian here for DNews.

  • It’s an interesting question, “why is space black?” Well fortunately, Fraser Cain,

  • who is brilliant and follows me on twitter and I am not worthy, recently discussed why

  • were not wearing shades 24/7.

  • Cain explains that the question was first asked by German Astronomer Heinrich Wilhelm

  • Olbers in 1823. It’s known as Olber’s Paradox, and states that if the universe is

  • infinite, static, and timeless, then the night sky should be lousy with stars. Obviously

  • though our night sky is more connect the dots than pointillism.

  • Edwin Hubble solved the paradox in 1929. He observed that everywhere he looked in the

  • universe, the spectrums of all the stars were slightly red, meaning the light coming from

  • them was being stretched out, meaning the space itself light was traveling through was

  • expanding. Ergo, the universe isn’t static and there must be stars that are so far away

  • their light just hasn’t had time to reach us yet.

  • So if we give it billions more years will we eventually be able to tan at midnight?

  • Don’t hold out too many hopes, because Hubble’s discovery of universal expansion also means

  • that the farther away something is, the faster the space between it and us is stretching

  • out. After a huge enough distance, space will be stretching out faster than light can close

  • the gap.

  • There’s another facet to the paradox though. Well, if the universe is all expanding away

  • from everything else, it stands to reason that if you go far back enough, it was all

  • clumped together. 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 see that too? Again, the riddle is solved by the expansion of space.

  • In 1964 Arno Penzias and Robert Wilson were working on a totally unrelated experiment

  • with a radio telescope and they couldn’t shake this weird, unwanted static. After making

  • sure everything was functioning correctly, even cleaning the inside of the antennae for

  • bird droppings for hours, they realized that the signal was coming from everywhere, and

  • you can’t stop the signal. They concluded that the Cosmic Microwave Background Radiation

  • must have been the light from the big bang, but had been stretched out after billions

  • of years until it was low-energy microwaves that our eyes can’t see. Boom, and the universe

  • makes sense again.

  • If you want to hear more possible evidence of the big bang, trace and Dr. Ian O’Neill

  • talk about gravitational waves and how they play into that over here.

  • What are some other implications of expanding space? I think it’s a great excuse to not

  • visit relatives, because, oh no, youre just getting farther away, awww dang. Let

  • us know in the comments and I’ll see you next time on DNews.

Ok so the universe is probably infinite, and there’s stars in every direction, and stars

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Why Is Space Black?

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    Cheng-Hong Liu posted on 2015/01/08
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