The images revealed bright deposits on the floors of some craters — a discovery shrouded in mystery without higher-resolution images –are actually clusters of rimless pits surrounded by halos of reflective material.
“The etched appearance of these landforms is unlike anything we’ve seen before on Mercury or the moon,” said Brett Denevi, a staff scientist at the Johns Hopkins University Applied Physics Laboratory, in a prepared statement. “We are still debating their origin, but they appear to be relatively young and may suggest a more abundant than expected volatile component in Mercury’s crust.”
In other words, Mercury’s surface might look a lot like the moon. But evidence of recent volcanic history suggests the planet has more going on than scientists thought.
Planets are born from the countless collisions of rocks and space debris that were part of the early Solar System. The heat from these impacts remains deep within the core of the planet, released through volcanic eruption. Mercury’s cratered appearance shows that there has been no volcanic activity on the planet for billions of years. This makes Mercury a dead planet.