The sos quest is given 48 hours after the date of the account's creation. A lvl 2 anomaly then appears. After successfully defeating this anomaly, 4 colonization ships are given, which can be used to colonize one planet. If you failed to defeat the anomaly, a second one will appear soon afterwards. The second anomaly will give you the colonization ships if defeated. The first anomaly is guaranteed to appear very close to the star system.
This quest reward will only be given once.
Note: there is a possibility that the 48 hours only applies after defeating a lvl 2 first