🚀 go-pugleaf

After having read the world coordinates proposal, I am still unclear as to how
the developers would describe this very simple problem:

	Given: A slit spectrograph with a single pointing position.  The
	dimensions of the data are two: one spatial coordinate and one
	spectral coordinate.  However, to describe the pointing, two
	spatial coordinates are needed, as well as the orientation of
	the slit, and the spectral dispersion and central wavelength.
	In other words, the data has only two dimensions, but it takes
	three dimensions to properly describe it.

Secondly, it appears that this convention is only relevant to skymapped
data--which I admit applies to most astronomical data.  However, it's hard to
see the relevance to solar images, for example.

Bill Thompson