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Possible "Ghost Crater" in Lakshmi Region (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)
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This NASA - Magellan Spacecraft image covers an area of approximately 100 by 120 Km (such as 62,1 by 74,5 miles) and is located in the Lakshmi Region of Venus, at 47° North Latitude and 334° East Longitude. Due to the extremely dense Venusian Atmosphere, primary Impact Craters of less than a 3 Km (such as 1,863 mileS) diameter are, in fact, nonexistent on the Surface of this Planet. However, the Dark Circular Region and the associated Central Bright Feature visible in this frame are reasonably thought to be the remnants of a Meteoroid that was smaller than the size necessary to create an actual Impact Crater but, anyway, that was big enough to leave some scars on the Venusian Surface.
Entering the Venusian Atmosphere at a low velocity (approximately 350 meters/second - such as about 1260 Km per hour) the Central Bright Feature appears to be a Cluster of Small Secondary Impacts, Ejecta and Debris from the original Meteor that broke up in the Atmosphere and, litterally, fell down in pieces. Even though most of the Meteorite did not hit the Surface, the Atmospheric Shock Wave/s that were generated by the Impact Event, could have been great enough to modify the surrounding Region. One explanation for this radar Dark Circular Formation - called "Dark Margin" -, could be that the Shock Wave/s was/were energetic enough to pulverize some portion of the Venusian Surface (remember that smooth surfaces generally appear radar dark).
Another explanation is that the Surface nere, could be blanketed by a fine material that was formed by the original Meteor's break up through the Atmosphere. Just out of curiosity, more than half of the Impact Craters found on Venus have associated "Dark Margins", and most of them are prominently located left of center of the Craters themselves.
This frame (which is an Original NASA - Magellan Spacecraft Radio-Image published on the NASA - Planetary Photojournal with the n. PIA 00477), since it is just a Radio-Image of the Venusian Surface and NOT a real view of it, has been colorized, according to an educated guess carried out by Dr Paolo C. Fienga (LXTT-IPF), in what they could reasonably be its possible Absolute Natural Colors (such as the colors that a human eye would perceive if someone were onboard the NASA - Magellan Spacecraft and, once the thick layer of Venusian Clouds and Fogs is completely overcome, looked down, towards the Surface of Venus itself), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team.
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(Dettagli)
