The universe is expanding, and accelerating, but not from a fixed point, it's expanding equally, and everywhere. I don't fully understand this myself, but I have watched and read it a few times. The constellations have changed, Halley (of comet fame) discovered that old star charts were slightly wrong compared to his view of the sky. If you are at the centre of a bubble, looking at a square drawn onto the inside wall from your perspective, and the bubble doubled in size, it would still look like a square, but it would be bigger. If you were not in the centre, but instead in a random point within the bubble, the same square shape could be interpreted as lots of different shapes, depending on your perspective. Also, because the universe is expanding ridiculously slowly in time relative to us, we can't see constellations changing overnight, it will be a gradual process. Add to that the fact that the earth is rotating on it's axis, while orbiting the sun, while orbiting the galaxy, means that over time, the stars will change places. That hubbub over a 13th astrology constellation came about because of a misunderstanding between the divisions of the sky as 360 degrees divided into 12 "sheets" to represent a month each, for calenders/horoscopes, and the actual constellations, and their location in the sky. The fuss was because the pole star has changed since the system was thought up thousands of years ago, because of the earth's rotational axis moving(albeit very small, as the Pole star is far away a small move in distance here looks a lot more dramatic further way[think of a lever]). I hope some of this makes sense, I don't have any formal qualifications (yes it's true), so this knowledge is mostly picked up from books, Brian Cox and other TV programs.