The discovery that helium and iron can mix at the temperatures and pressures found at the center of Earth could settle a long ...

To put that in perspective, the Earth is thought to be about 4.5 billion years old, which means these "rocks"—really ...

Primordial helium from the beginning of the solar system may be stuck inside Earth's solid core, new research suggests. The findings could have implications for a long-standing debate about how ...