Our approach is based on a gradient domain technique that preserves important local perceptual cues while avoiding traditional problems such as aliasing, ghosting and haloing.
We also describe the basic principle of white dwarf cosmochronology and its application in defining the age of the Galactic disk, globular clusters, open clusters and Galactic halo.
The end point of the collapse and relaxation of a protogalaxy is a dark matter halo, inside of which the baryonic gas is in hydrostatic equilibrium at a temperature of typically a few million degrees.