Pluto and Charon not in pdsImageProjection.trn
In $ISIS3DATA/base/translations/pdsImageProjection.trn, In the 'TargetName' group, neither Pluto nor Charon appear. Its been three years since New Horizons flew by, maybe time for those to be in there. - Ross Beyer
This originates from a github issue https://github.com/USGS-Astrogeology/ISIS3/issues/350
This sounds like a good thing to do.