Whether or not the frequency for this window is a sky frequency (i.e. as observed, not rest frequency). Normally false for spectral line work, could be true or false for continuum.

General Info
Name	isSkyFrequency
Type	Boolean
Visibility	private
Default Value	0
Owner	ScienceSpectralWindow
Is Read Only	false
Is Static	false
Aggregation	none
Is Derived	false