As what Douglas Adams says, "Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space."
The fact that the stars are very far from Earth, one can't fully understand the stars as it would require hundred of years to closely travel from earth to the stars because it is located million miles away from the Earth. Aside from its location, the stars are also hard to closely study because it emits lights that are harm for people when exposed longer.
