planet rioting

[Taqwus]

If an entire system is rioting, then you need to move in ships and land troops to quell the riot (if your happiness type appreciates this, that is). As soon as you get one planet to stop rioting, build a happiness facility (Temporal vacation facility if Temporal, urban pac otherwise; fate shrines (religious) and medical bays (organic) also help somewhat).

If your happiness type is neutral, watch out -- doing practically anything, such as colonizing, tended to hurt your happiness (at least in previous Versions. I've not used Neutral for a while -- preferring Peaceful, even with warrior races...).