
 Some may assume that he has way too much time on his 
      hands; others may applaud his sense of wonder. Either way, Professor Tim 
      Leighton took the initiative to work out 
what 
      a methanefall on Titan would sound like, based on what we already know 
      about Titan's gravity and atmosphere. (Since Titan's average temperature 
      is so cold that water exists only in its solid state, and the temperatures 
      hover around the triple point of methane, Titan can't have 
      
waterfalls...unless you're talking about cliffs of ice collapsing, 
      and that's not the same thing.)