A large chunk of Mercury may have been blown away by the sun

By Jonathan O’Callaghan

TIM BROWN / science PHOTO LIBRARY

A huge impact four billion years in the past would possibly well well hang resulted in Mercury dropping most of its mantle to deep place, potentially explaining undoubtedly one of the crucial planet’s key mysteries.

Mercury is unparalleled in comparison with other rocky planets in the characterize voltaic system as its iron core accounts for extra than 80 p.c of its radius, in comparison with objective correct 50 p.c for Earth. This makes it very dense with objective correct a thin mantle, about 500 kilometres thick, above the core. Astronomers hang long wondered why, with out a determined answer.

Now, …