Please help me identify this watch

Tonight my girlfriend was going through the belongings of her father who passed away. He was a medical doctor in Brazil and may have received it as a gift. He obviously didn't wear it. too dangerous to wear it in Rio. She found a lot of old watches but this one got my attention because I recognized the brand. It has the day/night sun/moon complication (if that’s the correct term) a second hand complication and what looks to be a little 24 hr single handed clock complication. You can see part of the mechanism through the dial. There is an Omega symbol on the stem piece. The weight that moves around inside says “omega” several times all over it. There is a plastic sticker covering the back so I can’t see very well what else it says there. On the dial it says Swiss Made. Hopefully the pictures and description will help with identification.