This is the famous "Cliff-face" firstly detected by Dr. Carlotto (according to Hoagland, 1987). A spacecraft above the line along Tholus and Cliff would get directly such shape by imaging 'Cliff' with camera pointing some 70 deg. off nadir. Here we did it by reducing verticals to 1/3 in the nearly orthonormal frame 35A73 (Viking-1976) which contains 'Cliff', 'J&L' and other Monuments.
See below our currently best assessment of orientation for such line Tholus-to-Cliff which goes along the axis of the Cliff-face. We conclude that artistic axis of F. Sacra and of Cliff-face are meant to be parallel and at some (17 +/- 2) deg. off meridian. Thus both suggest the minimal obliquity of planet Mars (and axis of phobian orbit) at around 1/2 million years ago (as correctly indicated by Hoagland, 1987).

Above scan is oriented with 'F. Sacra' in upright position; i.e., FRAME of FM at some 8 deg. from vertical. Since the axis of Cliff-face is also, obviously, in upright position it follows that F. Sacra is artistically with equal tilt as the artistic axis of Cliff-face. Meaning that when Mars has minimal obliquity so does the orbit and axis of Phobos. We have in total FIVE human faces of martians: those four in FM and the Cliff-face of Carlotto representing martian astronauts / cosmonauts in Phobos. See below scan of post-card which we send to friends this current, 2001 year, Christmas: an art-work, by myself, of phobians (in the back cover) with the already well known four in FM: It is headed totally in Latin, except the hand-written dedications and greetings inside and below F. Osculans & F. Ferox at noon.

Happy Christmas and New Year to the world. Our best wishes to everybody from UNIAM: Dimitri G. Lahoz (president), Angel Garcia (secretary) and Esteban who likes to sing that 'rom pum pum pum... Jesus smiled to me and my drum'.