David Rothery, The Open University: Mercury Keeps Getting Weirder
An image of Mercury via the MESSENGER spacecraft. This false-color image is enhanced to show the chemical, mineralogical and physical differences between the rocks that make up Mercury’s surface.(Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington).
For such a tiny planet, Mercury is a pretty big puzzle for researchers. NASA’s MESSENGER probe already has revealed that the planet is surprisingly rich in elements that easily evaporate from the surface, such as sulphur, chlorine, sodium and potassium. This is incredibly odd as these kind of substances most likely would disappear during a hot or violent birth – exactly the type of birth a planet so close to the sun, such as Mercury, would have had.
Scientists are also struggling to understand why Mercury is so dark and what its earliest planetary crust..
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