About the size of Pluto, Earth’s inner core is made of solid iron and helps power the magnetic field that protects life from harmful space radiation. Here's how scientists are learning more about the mysterious center of our planet: https://scim.ag/3t9 | Science

Plaque formation inside blood vessels begins when the inner lining becomes irritated by high cholesterol, smoking, high blood pressure, or inflammation. The inner lining is a thin layer of cells called the endothelium. When it becomes stressed, tiny openings form that allow cholesterol rich particles to slip beneath the surface. These particles settle in the vessel wall where they become oxidized. Oxidized particles trigger an immune reaction that attracts white blood cells. The white blood cell