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  2. Van Allen radiation belt - Wikipedia

    en.wikipedia.org/wiki/Van_Allen_radiation_belt

    Measurements from the Van Allen Probe B's Magnetic Electron Ion Spectrometer (MagEIS) show long electron lifetimes (i.e., longer than 100 days) in the inner belt; short electron lifetimes of around one or two days are observed in the "slot" between the belts; and energy-dependent electron lifetimes of roughly five to 20 days are found in the ...

  3. Earth's magnetic field - Wikipedia

    en.wikipedia.org/wiki/Earth's_magnetic_field

    A magnet's North pole is defined as the pole that is attracted by the Earth's North Magnetic Pole, in the arctic region, when the magnet is suspended so it can turn freely. Since opposite poles attract, the North Magnetic Pole of the Earth is really the south pole of its magnetic field (the place where the field is directed downward into the ...

  4. Geostationary orbit - Wikipedia

    en.wikipedia.org/wiki/Geostationary_orbit

    where F g is the gravitational force acting between two objects, M E is the mass of the Earth, 5.9736 × 10 24 kg, m s is the mass of the satellite, r is the distance between the centers of their masses, and G is the gravitational constant, (6.674 28 ± 0.000 67) × 10 −11 m 3 kg −1 s −2. [68]

  5. Geomagnetic pole - Wikipedia

    en.wikipedia.org/wiki/Geomagnetic_pole

    If the Earth's magnetic fields were exactly dipolar, the north pole of a magnetic compass needle would point directly at the North Geomagnetic Pole. In practice, it does not because the geomagnetic field that originates in the core has a more complex non-dipolar part, and magnetic anomalies in the Earth's crust also contribute to the local field.

  6. Magnetopause - Wikipedia

    en.wikipedia.org/wiki/Magnetopause

    If the pressure from particles within the magnetosphere is neglected, it is possible to estimate the distance to the part of the magnetosphere that faces the Sun.The condition governing this position is that the dynamic ram pressure from the solar wind is equal to the magnetic pressure from the Earth's magnetic field: [note 1] (()) where and are the density and velocity of the solar wind, and ...

  7. Dipole - Wikipedia

    en.wikipedia.org/wiki/Dipole

    By comparison, Earth has a south magnetic pole near its north geographic pole and a north magnetic pole near its South Pole. In physics , a dipole (from Ancient Greek δίς ( dís ) 'twice' and πόλος ( pólos ) 'axis') [ 1 ] [ 2 ] [ 3 ] is an electromagnetic phenomenon which occurs in two ways:

  8. Internal structure of Earth - Wikipedia

    en.wikipedia.org/wiki/Internal_structure_of_Earth

    The transition between the inner core and outer core is located approximately 5,150 km (3,200 mi) beneath Earth's surface. 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.

  9. Earth's inner core - Wikipedia

    en.wikipedia.org/wiki/Earth's_inner_core

    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]