Hi Monica, I wanted to welcome you to Cruise-Chat and wish I knew the answer to your question. I know there is a chapel and know they have some type of service, I believe it's an interdenominational (sp?) service. I have heard that mass was performed on some ships but I don't know any specifics or what ships. Hoping there is someone here that knows and can give you further assistance.
Monnie, I had the same question about the Carnival Miracle when I sailed in September. If RC is similar, they usually only have a priest on board for major holidays (i.e. Easter). It is possible, however, that a priest will be traveling on your cruise. If this is the case, I would assume that he would celebrate mass. Even if you call RC and and they tell you "no", check with the information desk while on-board when Sunday approaches.
As a last resort, you can spend some nice quiet time in the chapel on Sunday. It's not quite the same as making it to mass, but it's the best you can do and it is usually peaceful there.
Monnie, I thought I made it plain, but I guess not. The Skylight Chapel is on deck 15. They have services every Sunday. I don't know the times of the services, but there are both catholic and protestant services.
If there is a priest on board your ship, he may have a mass....I don't think there is anything planned....it just happens....but you could go to the chapel and have some private meditation time...Happy Sailing...