The discovery that helium and iron can mix at the temperatures and pressures found at the center of Earth could settle a long-standing debate over how our planet formed. Primordial helium from the ...

"In this case, we crushed iron and helium together under about 5–55 gigapascals of pressure and at temperatures of 1,000 Kelvin to nearly 3,000 Kelvin. Those pressures correspond to roughly ...