~1000
- Magnetic compass discovered in China.
1269
- Petrus Peregrinus , 'Epstola de Magnete'
1538-41
- Joao de Castro, on a voyage to the East Indies, made 43 determination of magnetic declination.
1544
- Georg Harman of Nuremberg discovered inclination.
1576
- Robert Norman rediscovered inclination (magnetic dip).
1600
- William Gilbert published in London 'De Magnete' : the Earth is a giant magnet.
1635
- Henery Gellibrand discovered the secular variation of declination.
1698-1700
- Halley's Voyages in the Atlantic Ocean.
1701
- Edmund Halley's sea chart of the whole world.
1721
- William Whiston's chart of inclination.
1722
- George Graham discovery of non-secular variation at London, that the compass
needle is continually in motion.
1741
- Discovery of the connection between magnetic disturbance and aurora, by
Graham at London, simultaneously by Celsius at Upsala in Sweden.
1768
- The 1st chart of inclination for the whole earth was published by Johann
Carl Wilcke at Stockholm.
1759
- The Solar Daily Variation is greater in summer than in winter was discovered by
Canton at London.
1820-35
- Arago observation of the magnetic declination at the Paris.
1825 and 1826
- Isodynamic charts for H and F were published by C. Hansteen.
1826
- Poggendorff introduced mirror-and-scale readings method.
1828
- Alexander von Humboldt constructed his own iron-free magnetic observatory in
Berlin.
1836-41
- The Gottingen Magnetic Union.
1838
- Gauss, Spherical Harmonic Analysis of the Earth's magnetic field.
1839
- Establishment of British Colonial Observatories by Sabine.
1846
- Chrles Brook constructed Photographic apparatus for recording magnetic variation
(Greenwich Observatory).
1851
- Discovery of the 11 year sunspot cycle by Samuel Schwabe.
1852
- Edward Sabine found the effect of sunspot cycle in disturbance of declination .
1859
- Richard Carrignton discovered solar flare.
1900-3
- Kistian Birkland Norwegian Scientists made experiments with beams of electrons
aimed at a magnetized sphere 'terrella' in vacuum chamber, leading him to propose
that the polar aurora is created by electron beams from the Sun.
1901
- Marconi successfully send radio signals across the Atlantic Ocean.
1930-1
- Sydney Chapman and Vicent Ferraro in England propose that magnetic storms are
caused when plasma clouds ejected from the Sun envelop the Earth.
1958
- Explorer 1, launched by the US, observes the radiation belt
- Pioneer 3 observes the outer radiation belt
- Eugene Parker propose the theory of the solar wind.
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