No Comet has ever been visited twice before, and therefore, the unprecedented pass of the NASA - Stardust-NeXT Spacecraft near the Comet Tempel-1 in the month of February of the AD 2011 gave Humanity a unique opportunity to see how the Nucleus of a Comet changes over time.
Changes in the Nucleus of Comet Tempel-1 were of particular interest because the Comet, as you knoow, was hit with an impactor from the passing NASA - Deep Impact Spacecraft in September 2005. Here is one digitally sharpened image of Comet Tempel-1 near the Closest Approach of Stardust-NeXT. Visible are many Surface Features which had been already imaged in 2005, including Impact Craters, Ridges and seemingly Smoother Areas (---> Plains). Only a few firm conclusions are yet available (as a matter of fact, the Comet Tempel 1 has been described by Astronomers as a "recipe for primordial soup" and, considering the list of the Comet's ingredients - id est: tiny Grains of Silicates, Iron Compounds, Complex Hydrocarbons with Clay and Carbonates thought to require liquid Water to form - might be quite appropriate for a cosmic souffle, since the Nucleus , which is approx. 5 Km long, is apparently porous and fluffy...) but, over time, the Astronomers who specialize in Comets and the understanding of the Early Solar System will be poring over these images, looking for new clues, such as, for instance, how Comet Tempel-1 is composed, how the 2005 Impact Site will appear, and how the General Surface Features of the Comet have evolved.
This frame (which is an Original NASA - Stardust-NeXT Spacecraft) has been additionally processed and then colorized, according to an informed speculation carried out by Dr Paolo C. Fienga (LXTT-IPF), in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - Stardust-NeXT Spacecraft and then looked outside, towards the Comet Tempel-1), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team. Different colors, as well as different shades of the same color, mean, among others, the existence of different Elements present on the Surface of Tempel-1, each having a different Albedo (---> Reflectivity) and Chemical Composition.