Like most moons of the Solar System, even the Saturnian moon Tethys is almost completely covered by Impact Craters (most of them still Unnamed). Some of these Craters bear witness to incredibly violent events which occurred on this Celestial Body in a far and distant past, such as, for instance, the gigantic Odysseus Crater (also known as "The Eye of Tethys", and seen here at the right - Dx - of the image). While Tethys is about 660 miles (such as approx. 1062,1644 Km) across, Odysseus Crater is roughly 280 miles (such as about 450,6152 Km) across, and therefore it covers - alone! - something like about 18% (eighteen per-cent) of the entire moon's Surface Area. If you want, you can consider that a comparably-sized Impact Crater on Earth, would be as large as the whole African Continent! This view looks toward the Anti-Saturn Hemisphere of Tethys; North is up and rotated 42° to the right (Dx). The picture was taken in Visible Light with the NASA - Cassini Spacecraft's Narrow-Angle Camera on April 11, 2015. The frame was acquired at a distance of approximately 118.000 miles (such as about 189.902,12 Km) from the Surface of Tethys and the Image Scale is roughly 3280 feet (such as approx. 0,999704 Km) per pixel This frame (which is an Original NASA - CASSINI Spacecraft's b/w and NON Map-Projected image published on the NASA - Planetary Photojournal with the ID n. PIA 18317) has been additionally processed, contrast enhanced, magnified, in order to allow the vision of the slightest details of the Surface, Gamma corrected and then re-colorized - according to an educated guess (or, if you wish, an informed speculation) carried out by Dr Paolo C. Fienga - in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - Cassini Spacecraft and then looked outside, toward the Saturnian moon "Tethys"), 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 other things, the existence of different Elements (Minerals) present on the Surface of Tethys, each having a different Albedo (---> Reflectivity) and Chemical Composition. Note: it is possible (but we, as IPF, have no way to be one-hundred-percent sure of such a circumstance), that the actual luminosity of Tethys - as it is in this frame - would appear, to an average human eye, a little bit lower than it has been shown (or, better yet: interpreted) here. |