MYSTERY RISING WITHIN MERCURY
THE GIST Mercury's massive iron core is even more massive than previously thought, accounting for 85 percent of the planet.
Gravity maps and computer models show that the core sports an extra solid layer of iron-sulfide.
Convection is probably behind the mysterious rising of Mercury's surface, which in some areas is now tilted.
Something besides volcanic eruptions and asteroid and comet impacts has sculpted the surface of Mercury -- an unknown process, possibly still going on today, that causes the ground to swell from the inside out.
The evidence, collected by a NASA spacecraft orbiting the innermost planet, is scattered all over Mercury, including a dramatic finding that half of the floor of the biggest crater on the planet has been raised above the walls.
The topographical mishmash is a visible manifestation of a much deeper mystery. New studies show Mercury's massive iron core is even bigger than expected, with a previously unknown solid layer of iron-sulfide buried beneath the mantle
- MYSTERY RISING WITHIN MERCURY - Theresa, 2012-03-22, 05:48