Is the Earth a magnet?
In a sense, yes. The Earth is composed of layers having different chemical compositions and different physical properties. The crust of the Earth has some permanent magnetization, and the Earth’s core generates its own magnetic field, sustaining the main part of the field we measure at the surface. So we could say that the Earth is, therefore, a "magnet."
But permanent magnetization cannot occur at temperatures above about 650 degrees Celsius (1,200 degrees Fahrenheit), when the thermal motion of atoms becomes too vigorous to maintain the ordered orientations needed for permanent magnetization. The core of the Earth has a temperature of several thousand degrees Celsius, and is not permanently magnetized.
Learn more:
Related Content
Why measure the magnetic field at the Earth's surface? Wouldn't satellites be better suited for space-weather studies?
Does the Earth's magnetic field affect human health?
What is declination?
Are we about to have a magnetic reversal?
How does the Earth's core generate a magnetic field?
Do animals use the magnetic field for orientation?
Could magnetic reversals be caused by meteorite or comet impacts?
Is it true that Earth's magnetic field occasionally reverses its polarity?
New 3D Measurements Improve Understanding of Geomagnetic Storm Hazards
Measurements of the three-dimensional structure of the earth, as opposed to the one-dimensional models typically used, can help scientists more accurately determine which areas of the United States are most vulnerable to blackouts during hazardous geomagnetic storms.
Mapping a Space-Weather Menace to Electric-Power Grids
New strides have been made toward quantifying how geomagnetic storms can interfere with the nation’s electric-power grid systems.
A Modern Compass Improves Oil Production
By using the Earth's magnetic field, combined with new innovative technology, oil and gas drilling companies are increasing oilfield productivity while reducing development costs and environmental impacts.
USGS, NOAA Mark 50 Years of Geomagnetic Research at Corbin, Va.
On May 23, 1956, a research center and observatory opened at Corbin, Va. to continuously monitor the Earth's magnetic field. It was charged by Congress "to enhance geomagnetic field studies and monitoring programs in support of scientific, general public, basic and national security needs of the United States."
Fredericksburg Geomagnetic Observatory
Main and auxiliary absolutes piers with Zeiss-Jena 010B Theodolites.
Deadhorse Geomagnetic Observatory
Absolutes pier at Deadhorse geomagnetic observatory.
Boulder Geomagnetic Observatory
Jeff Fox using a theodolite at the Boulder geomagnetic observatory.
Earth Science Week, Continued: Geomagnetism and the Self-Sustaining Dynamo Called Earth
USGS scientist Duane Champion explains the Earth's geomagnetic qualities and the potential for and possible consequences of a geomagnetic shift.
PubTalk 7/2004 — Secrets in Stone
The Role of Paleomagnetism in the Evolution of Plate Tectonic Theory Video Presentation
Presentation of the award-winning USGS video "Secrets in Stone" (35 minutes), introduced by Jack Hillhouse, Research Geophysicist, and followed by a tour of the USGS Paleomagnetics Laboratory
- Crucial discoveries in the early 1960.s were made
Chart showing the Earth’s magnetic feild
This is one of five world charts showing the declination, inclination, horizontal intensity, vertical component, and total intensity of the Earth’s magnetic field at mean sea level at the beginning of 2005. The charts are based on the International Geomagnetic Reference Field (IGRF) main model for 2005 and secular change model for 2005-2010. The IGRF is referenced to the
...Earth Cross-Section
A cross-section of the Earth, showing the sub-surface layers that are being mapped.