Circle Tangent on a sphere ?

 From:  Frenchy Pilou (PILOU)
5435.3 In reply to 5435.2 
Very simple ;)

I want click annywhere on the Sphere and draw a tangent circle* in one click (the best)! or 2 (challenger) or 3 (last chance) ;)

* circle is given !

Maybe something with helper line

for the moment
Orient then Project Curve is cool but you must erase the second projection

EDITED: 29 Sep 2012 by PILOU