What is the radius of the Earth's inner core made of iron and nickel?
The Earth's inner core has a radius of 1,220 kilometers. This sphere generates the planet's magnetic field through the movement of liquid iron in the outer core.
Common questions about Iron
Short answers, pulled from the story.
When did the Hittites first master the smelting of iron from ore?
The Hittites mastered the smelting of iron from ore around 1500 BC. This empire in Anatolia created a technology that eventually replaced bronze and spread across the Near East after their fall in 1180 BC.
How much iron is found in the human body and where is it located?
The human body contains about four grams of iron, which is less than 0.005% of total body weight. Three-quarters of this iron is found in hemoglobin, the protein that transports oxygen from the lungs to the muscles.
What year did Henry Bessemer invent the process for making steel?
Henry Bessemer invented a process for making steel in 1856 by blowing air through molten pig iron. This invention removed impurities and reduced the carbon content to make steel much more economical for mass production.
What temperature is required to smelt iron compared to copper?
Iron requires kilns reaching 1,538 degrees Celsius to smelt, which is far hotter than the 1,088 degrees needed for copper. This technological leap enabled the construction of stronger weapons, tools, and infrastructure.