- The new layer is a solid metallic ball of nickel and iron and is deep inside the inner core of Earth.
- Therefore, it is dubbed the “innermost inner core”.
- The ‘innermost inner core’ may be an iron ball with a radius of about 650 kilometres inside the inner core.
- It is solid due to high pressure deep within the Earth that stops iron alloy from melting.
- First hypothesised about 20 years ago, it was identified through data gathered from seismic waves caused by earthquakes.
Significance of the Fifth layer
- Provide information on past events on Earth that happened hundreds of millions to billions of years ago.
- Provide a new way to probe Earth’s inner core and its centremost region.
- Provide information about the evolution of the earth’s magnetic field etc.
The Four Layers of the Earth
So far, four layers of Earth’s structure had been identified. This includes:
- Crust
- It is the topmost or outermost layer of Earth, which makes up 1% of Earth’s Volume.
- It has two parts – a thinner Oceanic Crust and a thicker Continental Crust.
- Mantle
- Solid/plastic layer of earth which makes up about 84% of Earth’s Volume.
- It is divided into two parts – Upper Mantle and Lower Mantle.
- The uppermost mantle and crust constitute the lithosphere.
- Outer core
- The liquid portion of the core
- It is composed of 80% iron along with nickel and some other lighter elements.
- Inner core
- The solid portion of the core,
- It is composed of Iron and nickel with the presence of heavy elements like gold, platinum, palladium, silver and tungsten.
- It was believed that it was the hottest and densest of all layers.
- However, this new layer is denser than the other two cores.
Interesting Facts about Earth’s Layers
- Scientists can drill holes to study the earth’s crust but in order to study deeper layers they must study seismic waves.
- Iron and nickel are considered the two major components found on the earth’s core.
- It is believed that 80 per cent of the earth’s core is made of iron.
- There is enough gold in the core of Earth to cover the entire surface of the Earth in a 4-meter thick layer.
- The layer of the earth’s crust covering the entire planet is referred to as the “sima”.
Latest news about Innermost inner core
- 01 March 2023:
- A team of researchers has found evidence of a new layer of the planet sitting within the inner core.
- According to seismologists from The Australian National University (ANU), data gathered from seismic waves caused by earthquakes has shed new light on the deepest parts of the Earth’s inner core.