<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Tidal friction? Is there flowing water on mars?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>
Solid body tides. The theory of tidal friction began with elastic deformation of "solid" planets. Later, it was extended to liquid and gaseous bodies, where it works differently. Earth is a hybrid case because its tides rely on a combination of oceans flowing and land masses to block that flow. But tidal friction is the basic force that causes both our Moon, and Mars's moon Phobos, to slowly spiral. -|Tom|-