Space is big. Really big. You may think it's a long way down the road to the chemist, but that's just peanuts to space.

Imagine that our entire Solar System were the size of a quarter. The Sun is now a microscopic speck of dust, as are its nine planets, whose orbits are represented by the flat disc of the coin. How far away is the nearest star to our sun? Proxima Centauri (and any planets that might be around it) would be another quarter, two soccer fields away. This is the typical separation of stars in our part of the galaxy.