Published on March 22nd, 2012 | by James Johnson2
NASA MESSENGER Probe Reveals: Mercury Is Crazier Than We Thought
When the NASA MESSENGER probe set off for Mercury scientists expected to collect plenty of useful information about the planet and what they have found is that Mercury is crazier than they had previously believed.
The probe has revealed that Mercury’s core eats up 85 percent of the planet’s radius while consisting of three instead of two layers. The planet also features a probable solid layer. NASA MESSENGER also found that the solid layer is surrounded by a liquid iron layer that is encapsulated by a third solid iron-sulfur layer.
Results from the MESSENGER probe were presented on March 21 at the Lunar and Planetary Science Conference. Also presented were two paper which appeared online in Science.
One of the papers focuses on the gravity measurements that have led to a new model of the planet’s interior while the other paper focuses on the surface features of Mercury’s northern hemisphere.
According to ScienceNews:
Reconciling Mercury’s surface composition with its density has confounded scientists until now. Surface rocks don’t contain enough heavy elements, like iron or titanium, to account for the observed density when a standard, two-layered core is considered.
According to Steven Hauck of Case Western Reserve University in Cleveland:
“So we had to ask ourselves, ‘How could this be formed?’ The iron-sulfur shell surrounding the core solves that problem by providing the missing bulk. “It sits at the base of the rock layer, and we have high-density metal that sits right beneath it as a part of the total solid.”
Researchers have also found “wrinkly surface features” called fold-and-thrust-belts that show a shrinking planet in the midst of collapse. Fold-and-thrust-belts occur when the planet core cools and contracts. As the planets core shrinks the outer crust follows along causing pieces of crust to slide underneath other pieces of crust.
By studying old-and-thrust-belts scientists can try to determine how much Mercury has shrunk and when that contraction occurred.
Other findings can be read about via Science and in the meantime the MESSENGER probe was just approved for a one-year extension which could yield plenty of new and exciting findings.