Updated on
Summary
Mercury is even more of an iron planet than scientists had previously supposed. Richer concentrations of iron and titanium have been seen on Mercury's surface by Nasa's Messenger probe. Previous Earth and spacecraft-based observations had detected only very low amounts of iron. Because of its immense density, scientists have already assumed much of Mercury's interior contains iron. Messenger sees the surface iron bound up in oxides with titanium. The mission's principal investigator, Sean Solomon, said the new observations would keep theoreticians busy.
