The Earth acts as a magnet because of electric currents generated through the movement of iron in the Earth's molten core. This motion creates a very weak magnetic force that expands from Earth reaching tens of thousands of miles into space.Continue Reading
The electric forces emanating from the Earth's core result in electromagnetic forces with magnetic poles near the North and South Poles. These magnetic forces are why compasses point toward north; the magnetic component of the compass is attracted to the forces at the North Pole. The magnetic North Pole is slightly offset from the geographic North Pole. The magnetic axis of the Earth tilts slightly away from the axis of rotation, and this tilt varies from year to year. On average, the magnetic axis is about 11.3 degrees offset from the axis of rotation.
The magnetic field of the Earth keeps the planet safe from hazardous radiation in space. The sun constantly releases charged, radioactive particles. These particles are known as solar wind. The magnetic field keeps these radioactive particles from raining down on the surface of the Earth. As the particles approach Earth, the magnetic forces deflect them around the atmosphere. Without these forces, the particles would destroy the Earth's atmosphere and expose the plants and animals to deadly amounts of radiation. Scientists believe solar winds stripped the atmosphere from Mars because Mars does not produce protective magnetic fields.Learn more about Earth Science
Scientists agree that the Earth formed about 4.6 billion years ago out of accreted matter from the solar nebula. All planets in the solar system formed the same way. Once the proto-Earth was formed, many changes occurred over vast timescales to produce the Earth of the 21st century.Full Answer >
The one and only known home for life, Earth is one of the most interesting planets of the solar system. Life on Earth is extremely diverse; however, relative to Earth's size, all of life is contained within a very thin layer of its surface and lower atmosphere.Full Answer >
Astronomers theorize that over 4.5 billion years ago, Theia, an object about the size of Mars, collided with Earth to create a tilted axis. This is called "the giant impact theory." Prior to this event, the axis was straight at 180 degrees.Full Answer >
The Earth has a radius of 3,959 miles, a diameter of 7,926 miles and a circumference of 24,902 miles. Earth has a mass of 6.6 sextillion tons and a total surface area of 197 million square miles. It is the fifth largest planet in the solar system.Full Answer >