How do we measure the universe?

The universe is very large may be obvious, but sometimes it is worth remembering: the universe is very big ... if you think about it and ponder for a moment, the truth is not so obvious. Moreover, even really difficult to imagine how big it is.

Our usual measures are wasted when we put them face to face with the immensity that surrounds us. And one of the issues that most often appear when trying to measure the Universe is the same: How? How do astronomers know a star or galaxy is 8,000 million light years away?

how to observe the planets of our solar system

The planets of our solar system are on tomes some of the most rewarding and simplest sky watching targets to spot, if you know when and where to look. Here's a look at how to observe the planets of the solar system in 2011. Some have worlds of their own.

Astronomer’s measure distances in the sky in terms of degrees. For reference, your clenched fist held at arm's length covers about 10 degrees of the night sky.