Definition of Outer Core

In another example, the possible presence of hydrogen in the Earth`s outer core suggests that the accretion of Earth`s water[14][27][28] was not limited to the later stages of Earth`s accretion[23] and that the water may have been absorbed into metals forming nuclear fuels by an ocean of anhydrous magma. [14] [29] Unlike Earth`s solid inner core, its outer core is liquid. [5] Evidence of a liquid outer core includes seismology, which shows that seismic shear waves are not transmitted through the outer core. [6] Although the outer core has a similar composition to earth`s solid inner core, it remains liquid because there is not enough pressure to keep it in a solid state. As the Earth`s core cools, the liquid freezes at the inner boundary of the core, causing the solid inner core to grow at an estimated rate of 1 mm per year at the expense of the outer core. That`s about 80,000 tons of iron per second. [11] The numerical value of the outer core in Chaldean numerology is as follows: 5 The Earth`s outer core is a layer of liquid about 2,200 km (1,400 miles) thick, composed mainly of iron and nickel that lies above the Earth`s solid inner core and under its mantle. Its outer limit is 2,890 km (1,800 miles) below the Earth`s surface. The transition between the inner core and the outer core is about 5,150 km (3,200 miles) below the Earth`s surface. Unlike the inner core, the outer core is liquid. The inner core is also known as the solid core. Lehman was the first to identify the Earth`s solid inner core and also became a leading expert on the structure of the upper mantle.

She was the first woman to receive the prestigious William Bowie Medal, the highest honor of the American Geophysical Union.