Why is space so dark even though the universe is filled with stars?
Well, remember that our universe is expanding at an ever-increasing acceleration. The galaxies beyond the Observable Universe (OU horizon at 46 billion light years away) are now traveling faster than the speed of light (c=300,000Km/seg), hence, the light from those galaxies shall never reach our telescopes any longer. The OU is getting smaller every day due to this expansion. Every year, many millions of stars reach a speed greater than c, and their light is lost forever. In fact, our universe is getting darker and darker because our OU shrinks. In a very long-term future (if we don’t destroy ourselves before), the only universe we see shall be that of our own local galactic neighborhood (the Virgo cluster), which means that more than 99.99% of the universe shall be unobservable. By the way, watching the sky using a telescope capable of filtering different light wave lengths shall look like this (American Museum of Natural History):
So, do look at the stars at night while you can.
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