Defiance is the outer planet in the Independence system.  It’s a very appropriate name.  A tiny little toxic, corrosive ice ball with only trace atmosphere, it takes a particularly defiant individual to live there.  We probably never would have bothered with the place if it weren’t full of valuable minerals and if her low gravity hadn’t made it easy to mine.  But those factors make Defiance a surprisingly attractive world.  For certain definitions of the term.