ᐅ Existing structure (built in 1961) – reinforced concrete ribbed slab – opening

We are planning a major renovation of a single-family house built in 1961.
The ceilings on the ground floor and the upper floor are constructed as reinforced concrete ribbed slabs.
(Ground floor: Rib direction E <-> W; Upper floor: Rib direction N <-> S)

I would like to create an opening in the bedroom ceiling to have a view of the sky/stars.
Before I approach a structural engineer with this request, I wanted to ask if there are people here with experience in reinforced concrete ribbed slabs who could roughly tell me if such an opening is even possible and affordable.

I wouldn’t attempt to alter this massive ceiling structure. I also think it’s not so straightforward from a structural engineering perspective to create an opening here.

What you might consider is drilling a core hole through the ceiling. Then you could run a PVC pipe (also known as DWV pipe) from your bed up through the roof. That way, you could watch the stars from your bed. The larger the hole, the more stars you’ll see.

Depending on how the sun rises, you could also get some sunlight in bed in the morning.

Since your roof structure lacks the intermediate purlins, I consider the ceiling to essentially act as the bottom chord of a two-part truss system. This makes the request at least ambitious. If you are using corrugated fiber cement roofing sheets, you might also face more urgent issues.

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Sorry for the late response.
The roofing with Eternit sheets (yes, they contained asbestos) has long since been replaced with standard clay tiles.