The Alpha Centauri system is the clostest inhabited system to Sol, as it was the first system ever colonised by Humanity in 4175. Thought to be an Empire stronghold due to a massive military presence at the Sol end of the connecting Warp Hole, this was not the case as the system was embroiled in a civil war between League supporters and Empire loyalists. The system presumably was siezed by the League following their victory and the Closure of Sol warp hole.
- Erato - One of three planets held by League loyalists during the First Colony War
- Ballistus - Held by League Loyalists during First Colony War
- Callopia - Under control of League revolutionary government during First Colony War