I don’t know how to replicate this, but this is from me exploring. Sometimes I am not on when the ship enters orbit, and it could have caused this problem.
What galaxy is this from?
I would guess it parked there when offline and didn’t update info until it moved.
I get this too, send ship to planet, logoff before it arrives and exploration not done
Yea, I noted this too. It happens after you logoff.
I created a bug for this. If after ordering a fleet to a planet’s orbit you are then offline when it arrives, that planet will not be remembered in exploration history (and why it shows as unexplored still on the label even though your fleet is in orbit). As soon as the fleet leaves that planet’s orbit it becomes unexplored. Even if you move the fleet a little in orbit, it still won’t be remembered after leaving.
It’s similar with a star system if you don’t enter orbit of any planet. Order a fleet close enough so that the system will be in scanner range, or even enter the system, but if it arrives while you’re offline it will be forgotten as soon as the system is no longer in sensor range.