Making a cardioid shape

I am wondering what is the best way to create a cardioid shape. I am assuming creating a circle and adding an edit point which to drag to the center would do it, but it has been a while since I’ve been in the program and can’t quite get the results I am looking for.

I am looking to recreate this bubble over the microphone in the photo.

Rhino 5 for mac


Create a section curve with the desired shape and use Revolve to create the surface.

Perfect! thank you David