The Tranquility server will be taken offline at 18:30 UTC and is scheduled to be back online again at 19:00 UTC. The reboot is necessary to deploy EVE Online: Inferno 1.1.4 which fixes an issue with unicode characters that prevents some players to experience EVE Online in the designated way.
We apologize for any inconvenience caused by this and work on a speedy and smooth deployment and reboot.