How to make a niche out of an object Hello!

This is my very first post on this site, so please excuse me if something is not clear or the structure is bad.

Anyways, I am making a very detailed model of an engine, and I am having trouble with making this little niche or how to call it (highlighted - red color). As you can see in the picture, it's coming out of "top" part and smoothly joining the rounded tube.







Any ideas on how to make that? Your help would be so much appreciated!

Best regards,
-T
I would do it this way: Once you've created your sphere, create a mesh with an edge that follow the profile of your excrescence. Once in top view use the Knife Project tool to project the profile on the sphere surface. Now join and delete some vertices, extrude up, close the top, create the small hole, etc... Maybe use the Mirror modifier to duplicate the shape all around, or duplicate this part 3 times, rotate it and paste it all around with the Snap (Vertices mode) + Automatically Merge options activated, and at the end create somme additional edges to sharp the edges.



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