Search results
Results From The WOW.Com Content Network
Earth's inner core is the innermost geologic layer of the planet Earth. It is primarily a solid ball with a radius of about 1,220 km (760 mi), which is about 20% of Earth's radius or 70% of the Moon's radius. [1] [2] There are no samples of the core accessible for direct measurement, as there are for Earth's mantle. [3]
Earth's inner core is the innermost geologic layer of the planet Earth. It is primarily a solid ball with a radius of about 1,220 km (760 mi), which is about 19% of Earth's radius [0.7% of volume] or 70% of the Moon's radius. [32] [33] The inner core was discovered in 1936 by Inge Lehmann and is composed primarily of iron and some nickel. Since ...
Cutaway of the Earth showing the inner core (white) and outer core (yellow). Inner core super-rotation is the eastward rotation of the inner core of Earth relative to its mantle, for a net rotation rate that is usually [clarification needed] faster than Earth as a whole.
The inner core is anisotropic, causing seismic waves to vary in speed depending on their direction of travel. P-waves, in particular, move more quickly along the inner core's rotational axis than across the equatorial plane. [42] This suggests that Earth's rotation affects the alignment of iron crystals during the core's solidification. [46]
The existence of an inner core was proposed by Adam Dziewonski and Miaki Ishii to explain the discrepancies in certain fits to travel-time wave models of the inner core. [1] It is contested whether the innermost inner core is a distinct entity, and it is claimed that the data can be explained in other ways.
In the Pressure and Gravity section, change The acceleration of gravity at the surface of the inner core can be computed to be 4.3 m/s2;[22] which is less than half the value at the surface of the Earth (9.8 m/s2). to The acceleration of gravity at the surface of the inner core can be computed to be 0.43 m/s2;[22] which is less than 1/20 the ...
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Donate
The Hollow Earth is an obsolete concept proposing that the planet Earth is entirely hollow or contains a substantial interior space. Notably suggested by Edmond Halley in the late 17th century, the notion was disproven, first tentatively by Pierre Bouguer in 1740, then definitively by Charles Hutton in his Schiehallion experiment around 1774.