wiki Word: Hubble red-shift and Hubble Law

Definition: It is a theory that suggests everthing in the universe is still expanding and getting farther apart. This theory is used to determine how far away objects are that are farther away that 1 billion light years.

 Hubble invetened his theory in 1931. Without this theory we would not be able to tell the make-up and distance of planets over a billion light years away. Also we wouldnt understand that the universe may be expanding and in a couple of thousand years from now we would look for a glaxy or planet and it wouldnt be where it was supposed to be.

 We need to study this term if we want to understand the universe. If we didnt use this law we would not have an accurate distance for planets taht were over a billion light years away, and we wouldnt be able to determine what they were made up of. If we didnt use this theory we might think something had the resources to contain life, and we would study it. If it didnt though, we wouldnt be able to tell and we would spend time studying a worthless planet.

 Newman, Phil. "Redshift and hubble's law." Starchild. Starchild Team. 1 Jun 2008 <http://starchild.gsfc.nasa.gov/docs/StarChild/questions/redshift.html>.