How can the Universe expand?

When you look around you, the Universe does not really seem to be expanding. Other people don't seem to be growing or moving away. However, on large scales, the Universe is indeed getting bigger. In the 1920s Edwin Hubble found that almost all galaxies were actually moving away from our own. But, there is nothing special about our galaxy.

Figure 1

Think of a balloon as it is being blown up (Figure 1). If you take any point on it, then all the other points seem to be moving away from it. It is the same with galaxies. We are merely a point on the balloon and all the other galaxies are moving away. If we lived in another galaxy, we would experience the same thing.

* Click here to learn how expansion is related to distance

* Click here to discover how to find out how fast a galaxy is moving away from us