Addtional metadata in 
the parts and chunks can be used to implement SODA cutout by using the WCS metadata in the chunks to
compute the sky-to-pixel transformations necessary to extract a subset of the pixels from a larger 
data array.</p>

<p>The WCS metadata in the chunks can also be used to compute most of the Plane metadata (position, 
energy, time, and polarization) in a consistent/uniform way. This strategy supports the option to 
shift some responsibility from the data provider to the metadata servic