The Fixed Stars

The Universe is vast. We can see out to a distance of about 13 billion light years (a light year is the distance travelled by light in year). All the stars we can see, and the galaxies that contain them are moving. The largest part of the velocity of most stars and gal axies is away from us, but some stars have a component of velocity at right angles to this. For stars that are close to us, we can detect and measure this movement. More distant stars and galaxies appear not to move. Their position relative to one another is fixed and they are called the fixed stars. When we talk of any stellar object moving across the sky, we measure this movement relative to the fixed star.

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