From a reader…
Which bishop, if any at all, do priests pray for during the Canon of the Mass if a ship is at sea? Would it be the bishop whose diocese is closest? Would it be the bishop whose diocese the ship embarked? I could imagine that military ships pray for the Military Ordinary, but what about us non-military?
The priest is to say the name of the bishop of the territory where the Mass is being celebrated. Even if he is with a group of pilgrims from the Diocese of Black Duck, and they are travelling through the Archdiocese of Metropolis, they say the name of the Archbishop, not of their own Bishop of Black Duck. An exception is, for example, on military ships which are covered by the Archdiocese for the Military Services.
Dioceses are regions of land, not oceans. They would include bodies of water such as lakes and rivers, but they would not extend out into the, say, Pacific beyond a very short way.
Under the old Code, if I am not mistaken (I’m writing this on the fly), people were covered by the jurisdiction of the port whence they departed. This is why I believe your planet’s Moon is under the jurisdiction of the Diocese of Orlando, since (then) Cape Kennedy was in that diocese. If that was the case under the older Code, I suppose there would be something similar via the newer Code.
I am not quite sure how the Apostolate of the Sea would fit into all of this.
Another thing comes to mind, if the priest truly doesn’t know the name of the bishop, he can simply leave the proper name out… except in Rome. In Rome he leaves out the whole phrase about the diocesan bishop, because he has mentioned the Pope and the Pope is the diocesan bishop.
If memory serves, there was once a papal permission given to a priest to have Mass aboard the infamous zepelin Hindenburg…. without candles. Perhaps someone could dig that document up and learn whose names were to be mentioned.
Another point to consider deals with the calendar, which liturgical day to observe. Imagine being close to the International Date Line, or on a ship that’s moving really fast, like the International Space Station.
It’s all a blur.
Bottom line: When I don’t know the name, I just leave it out and say “Antistite nostro… our Bishop”, and move on. I’ve prayed for the local bishop. God knows the name, even if I had forgotten it when I got to that point.