The Enterprise was at Rigel 7 where some of Pike's crew were killed and injured. At the beginning of "The Cage" Pike is headed from Rigel to the Vega colony to take care of their sick and injured. But why is Pike going to Vega instead of Earth? Rigel is about 860 light years from earth. Vega is about 25 light years from earth. Running some basic calculations based on the positions of Rigel, Sol, and Vega, that puts Vega at about 881 light years from Rigel. That means Earth is about 21 light years closer.