1.2K views · 135 reactions |  Where in the world are you? And how in the world do you know? Finding your exact location relies on calculating the precise center of Earth’s mass, which is easier said than done. Researchers rely on telescopes, lasers, and math to precisely calculate Earth’s geocenter. | NASA’s Goddard Space Flight Center | Facebook

If the core of Earth was less dense than its mantle. Due to gravitational instability, the planet turns inside out. The dense matter sinks and the light core rises. Made using SpaceSim. | Cosmoknowledge