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
The Future and Its Enemies Edward Younkins, a professor at Wheeling Jesuit University, wrote for the journal "Free Life" praising the book as a "brilliant, bold, and compelling new work". He also referred to it as "a must-read for anyone interested in commerce, technology, public policy, and the search for truth in a dynamic world." The Future and Its Enemies The Future and Its Enemies: The Growing Conflict Over Creativity, Enterprise, and Progress is a 1998 book by Virginia Postrel where she describes the growing conflict in post-Cold War society between "dynamism" – marked by constant change, creativity and exploration in the pursuit of progress