The temperature of the inner core can be estimated [...] from 5,000 to 6,000 °C (>9,000 °F).[8] The range of pressure in Earth's inner core is about 330 to 360 GPa (over 3,000,000 atm),[9] and iron can only be solid at such high temperatures because its melting temperature increases dramatically at these large pressures
Isn't this kinda old? Nazis did it in the 40's already! Eventhough they're not gonna find them there, they alread fled to a secret Moonbase called Valhalla with the UFOs they got from the lizardmen living in the centre of the Earth.