[time-nuts] nubie querie

[Don Collie jnr]

I`m not sure that questions like these is welcome on this list, but here goes anyway : 

1/ What are the the 10 sources of the most constant [invariant] frequencies known to man, in order of decreacing constancy? Four immediately come to mind.

2/ What is the mechanism in an oscillator, that is responsible for phase noise? [In only one sentence please]
If this is known, then it becomes easier to design low phase noise oscillators.

I hope you enjoy these questions,.................................Don.