Standard of rest to use when aligning SpecFrames


This attribute controls how a SpecFrame behaves when it is used (by astFindFrame or astConvert) as a template to match another (target) SpecFrame. It identifies the standard of rest in which alignment is to occur. See the StdOfRest attribute for a desription of the values which may be assigned to this attribute. The default AlignStdOfRest value is " Helio" (heliocentric).

When astFindFrame or astConvert is used on two SpecFrames (potentially describing different spectral coordinate systems), it returns a Mapping which can be used to transform a position in one SpecFrame into the corresponding position in the other. The Mapping is made up of the following steps in the indicated order:



All SpecFrames have this attribute.