A journey to the centre

Inside the Earth

It is 6,371 km from the ground under your feet to the centre of the planet. The deepest hole ever drilled is 12 km. Scroll down to travel the rest of the way, and click anything you see.

Time after the earthquake 00:00 P P through inner core S
Scroll to descend
The whole planet

A slice out of the planet

The same layers on the whole globe. Drag to turn it, and click any layer. The blue lines are Earth’s magnetic field, made by liquid iron moving in the outer core.

The numbers

Hotter, more squeezed, denser

Three things change as you go down: temperature, pressure and density. The sudden jumps mark the boundaries between layers. Temperature is the hardest to measure, so the shaded band shows the range of scientific estimates. Hover or tap to read any depth.

Good to know

What is real, and what is simplified

Real

  • The depths, temperatures and pressures come from the standard scientific model of the Earth’s interior.
  • The earthquake-wave paths are calculated, not drawn by hand, so the shadows fall where they really do.
  • “True scale” really is to scale. Try it to see how thin the crust is.

Simplified

  • The slice shows a typical meeting of plates, not a real place on the map.
  • In “Exaggerated” view the thin outer layers are stretched so you can see them.
  • The colours are only there to tell the layers apart. Real rock that hot would glow orange-white.
  • Everything is hugely sped up. The real mantle moves a few centimetres a year.

Still unknown

  • The exact temperature of the core (give or take about 500 °C).
  • What the two giant blobs at the bottom of the mantle are made of.
  • How old the inner core is.

Want more? Every panel has a “Go deeper” section, and the detailed version of this page adds earthquake-wave speeds, gravity and the debates among scientists.

Sources
  1. Dziewonski & Anderson (1981). Preliminary reference Earth model. Phys. Earth Planet. Inter. 25, 297–356.
  2. Kennett, Engdahl & Buland (1995). Constraints on seismic velocities in the Earth from traveltimes (ak135). Geophys. J. Int. 122, 108–124.
  3. Lehmann (1936). P′. Publ. Bur. Cent. Séismol. Int. A14, 87–115.
  4. Katsura et al. (2010). Adiabatic temperature profile in the mantle. Phys. Earth Planet. Inter. 183, 212–218.
  5. Anzellini et al. (2013). Melting of iron at Earth’s inner core boundary. Science 340, 464–466.
  6. Murakami et al. (2004). Post-perovskite phase transition in MgSiO₃. Science 304, 855–858.
  7. Pearson et al. (2014). Hydrous mantle transition zone indicated by ringwoodite included within diamond. Nature 507, 221–224.
  8. Garnero, McNamara & Shim (2016). Continent-sized anomalous zones with low seismic velocity at the base of Earth’s mantle. Nat. Geosci. 9, 481–489.
  9. Davies & Davies (2010). Earth’s surface heat flux. Solid Earth 1, 5–24.
  10. Lay, Hernlund & Buffett (2008). Core–mantle boundary heat flow. Nat. Geosci. 1, 25–32.
  11. Pham & Tkalčić (2023). Up-to-fivefold reverberating waves through the Earth’s center and distinctly anisotropic innermost inner core. Nat. Commun. 14, 754.
  12. Yuan et al. (2023). Moon-forming impactor as a source of Earth’s basal mantle anomalies. Nature 623, 95–99.
  13. U.S. Standard Atmosphere (1976). NOAA / NASA / USAF.
  14. Surface imagery: NASA Earth Observatory, Blue Marble Next Generation (public domain).