Planetary core has an observed magnetic field, which is believed to be generated within its metallic core. Mercury's core occupies 85% of the planet's radius, making it the largest core relative to the size of the planet in the Solar System; this indicates that much of Mercury's surface may have been lost early in the Solar System's history. Mercury has a solid silicate crust and mantle overlying a solid iron sulfide outer core layer, followed by a deeper liquid core layer, and then a possible solid inner core making a third layer. The composition of Venus' core varies significantly depending on the
Faith in the Earth all. The Earth represents our one and only window of opportunity, at the same time as it symbolizes all of our unknown higher potentials. Neither spaceman nor God will come to save us. But this is not a bleak dystopian materialism, because just as our simian ancestors couldn't realize that the development of their vocal cords (something they already had at least in rudimentary form) would open up those new dimensions of reality that we call language, civilization, and culture, just so we ourselves cannot yet get our minds around what we might be able to do already in rudimentary