Why Space Is Dark ?
If there are all those stars bright and shining up in the sky at night so why do you think it is so dark. Millions of stars shining, those hundred billion galaxies so don’t you feel these are not enough to light up the sky at night as day. Or do u think it is because sun is not up there during night. Different views but are those true? Doesn’t’ this all sound interesting?
Let’s understand this by understanding why space is dark ? Space has countless stars that are all brightening up like the sun. No matter what direction you look at you would see countless number of stars or a galaxy. So that means space should be as bright as the sun, no matter what time of the day morning or night. But this is not so.
But why is it like that? Does this mean there is some distance where the stars are stopping or is there some boundary or an edge to this universe? Not really, we all know space is boundless i.e. it has no edge. But this interesting universe does have an edge, and it is not spatial but just a temporary one.
We all know universe had a beginning. And so since the beginning there is a possibility that the stars that might be needed to fill up the space with lightning might not have reached yet. Light takes time to travel across the universe and when we point our telescope at something really that far we’re actually seeing that part as it was when the light had emitted. So when we look at that light so far and so old, is not the reason that there is light in space because the star haven’t yet reached.
Then what is the actual reason for why space is dark ? We saw that even if seen through a telescope so far we still do see light. So when the Hubble telescope took a picture of the stars, it took it using an infrared camera. We all know the universe is expanding and the stars and galaxies up there are moving away from us due to this. So when they start moving away it starts to become redder and redder until they become infrared. And these infrared stars and galaxies cannot be seen by our human eyes. And hence it appears dark in space. And so finally we know why it is dark at night and in space.
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