Today, on the evening of October 21st, there are issues with the servers in Destiny. The connection to the PSN fails during login.
Update 8 PM: You can log in again.
The Guardians on PS4 and PS3 are currently reporting issues: They cannot log in. There is a message that the connection to the PSN fails.
Earlier this afternoon, there were difficulties with the PlayStation Network, which temporarily affected various online services. However, the current PSN status indicates that all services are operational.
Bungie has already spoken out. They are aware of the issues on PS4 and PS3. However, it is not known how long these will last.