Geomagnetism

An aurora ( aurorae or auroras) is a natural light display in Earth’s upper atmosphere caused by charged particles from the Sun colliding with atoms in the atmosphere. These collisions excite oxygen and nitrogen, which then emit light of different colors such as green, red, and purple. When observed in high-latitude regions they are called polar lights and aurora polaris. In the Arctic they are called northern lights (aurora borealis); in the Antarctic, the terms southern lights (aurora australis) are used. Auroras display dynamic patterns of radiant light that appear as curtains, rays, spiral

magnetic field that extends from the Earth's inner core to where it meets the solar wind

thumb|300 px|Artist's impression of a magnetosphere

zone of energetic charged particles around the planet earth

temporary disturbance of the Earth's magnetosphere caused by a disturbance in the interplanetary medium

angle on the horizontal plane between magnetic north and true north

point in the Arctic at which Earth's magnetic field points vertically downwards, at 86°N 175°E in the Arctic Ocean as of 2019

fluid layer composed of mostly iron and nickel between Earth's solid inner core and its mantle

wandering point on the Earth where the geomagnetic field lines are directed vertically upwards, at 64°S 137°E as of 2015 in the Southern Ocean

angle made with the horizontal by the Earth's magnetic field lines

mechanism by which a celestial body generates a magnetic field

REDIRECT Earth's magnetic field

anomaly of the Earth's or other astronomical object's magnetic field

error of a magnetic compass caused by local magnetic fields

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book by William Gilbert

detecting parameters of the magnetic field of the earth by flying over the earth's surface

network of devices used to wirelessly locate objects inside a building

Ground level manifestation of space weather

one of two antipodal points in the Arctic and in the Antarctic where the axis of a best-fitting dipole intersects the surface of Earth

long-term non-periodic variation

thumb|Magnetotelluric station

observatory, research institute and museum in Turkey

thumb|right|A series of images made by ultraviolet light imager on the Polar (satellite)|Polar spacecraft showing the aurora and Earth's upper atmosphere. The glowing side is the atmosphere lit up by the Sun's light energy and the oval of light is the aurora. During a substorm the auroral oval brightens in a localized area and then suddenly breaks into many different forms that expand both toward Earth's pole and equator. This is exactly what Shun-ichi Akasofu (1964) drew in his auroral substorm illustration. thumb|Short video featuring commentary by David Sibeck, project scientist for the THE

instrument which measures very small variations in the Earth's magnetic field

standard model of the structure of Earth's magnetic field

used to measure the angle between magnetic dip and the horizon

the migration of the magnetic poles over a planetary surface

simple approximation of Earth's magnetic field

study of magnetism in rocks

global network of observatories, monitoring the Earth's magnetic field

depth at which rocks in a specific geographical area encounter the Curie temperature

sheetlike region of denser (0.3–0.5 cm⁻³) hot plasma and lower magnetic field near the equatorial plane, between the magnetosphere’s north and south lobes