Eli5: Shouldn’t light from distant stars and galaxies appear to be continuously blinking by tons of space debri constantly moving between it and us through the Billions or year?

Question

Hopefully the question makes sense. But it seems like we are always getting such great photos of these objects. You would think that one day you may be able to see a galaxy; while the next it may be completely obstructed by another object that is closer to earth but still thousands to millions of light years away.

In: Planetary Science

Answer 1

The short answer to this is that space is almost entirely empty space. Like mind bogglingly empty. When you look up in the sky it looks packed with stars, but in reality the vast distances of empty space between them are so immense it’s hard for our minds to comprehend. The time scale for one object to move enough to obscure another that we are looking at is likely to be millennia at the smallest.

That said, there are things like nebula, clouds of dust and gas, that can block our view of things. In those cases we use telescopes that operate in different wavelengths, like infrared, to see through them.