Hi,
I am new to GH, so this is a very simple question:
I am trying to create a surface which is tangent to a sphere on a given
point. I have succeeded in creating a plane like that, but when turning
the plane into a surface, it is automatically placed with its corner -
rather than center - coinciding with the point on the surface. Is there a smart way of changing that - or a better way of making tangent planes all together?

Thanks,
Anne