Comparisons Between New Horizons Results and Long-Term Monitoring of Pluto

The New Horizons encounter data have revealed a diverse and complicated surface and atmosphere for Pluto showing strong correlations between geologic features and the albedo and compositional units known from ground- and HST-based observations over the decades prior. This presentation will delve into detailed comparisons between the long time base and low spatial resolution data and the new high resolution snapshot of Pluto from the flyby. Special emphasis will be placed on the albedo and near-infrared spectral evolution over time. We will compare the albedo maps from the late 1980's built on mutual event data and two epochs of HST observations against the New Horizons images, after correcting for viewing geometry. Also included will be a discussion of the evolutionary trends in the hemispherically averaged spectral properties from Lowell Observatory and IRTF data against the resolved compositional and spectral maps from New Horizons. The combination of these data sets now permits an unprecedented ability to constrain time-variability on the surface from apparent changes due to viewing geometry and surface inhomogeneities. These comparisons require a reconcilliation of surface scattering properties that are enabled by the firm determination of the size of Pluto.