The China Lake Museum is definitely worth a visit, although it helps
if you have a fondness for missiles:

http://www.chinalakemuseum.org/

It is on base, but they give you a guest pass at the gate to get to
the museum.  And as long as you're in Ridgecrest (which means you have
nothing else to do), you might as well stop at the Maturango Museum.
It's very good also.

http://www.maturango.org/