Exploded cut-away diagram showing the internal structure of the terrestrial planet Mercury. Mercury, the smallest true planet, is world of rock and iron with a substantial iron core. Following a scientific study by NASA’s Messenger probe, astronomers now believe that the core is even larger than previously held. From the centre outwards, there is a solid iron core (radius 1000 km), a liquid iron core (1950 km), a possible layer of iron sulphide (50 km thick), a silicate mantle (400 km thick) and a rocky crust (40 km deep). The core is very large compared to the planet’s radius, which suggests that much of the planet’s original mantle was removed in a devastating impact with another body, deep in the Solar System’s early history. | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Garlick, Mark |
Taille de l’image : | 6000 px × 3600 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |