Missing Star Field in Time Machine
My system Yosemite 10.10.4 I've frequently used Time Machine as back up with no problems. Yesterday after I finished backing up, ejected the external back up drive I always use, I re-connected the same drive, and when I entered Time Machine, the Star Field did not open as usual: What I now see displayed are the normal series of desktop views superimposed on each other, with the normal side bar of past dates, but instead of the normal star field, I now have a pale and fuzzy view of what seems to be my normal desktop background. Other than the missing Star Field, everything else seems to be normal. However I am concerned about what else may be affected. Thanks for your help.
Mac Pro, Mac OS X (10.6.8)