Database

Types of Magnetic Data Used in Modeling

• Observatory

  There are approximately 250 permanent observatories in operation around the world. These stations take continuous measurements of the Earth's magnetic field and report these values to World Data Centers.

• Satellite

  Most of the data used in modeling the main field comes from the high quality magnetic satellites:

  • Polar Orbiting Geophysical Observatory (POGO 1965-1971)
  • Magnetic Field Satellite (Magsat 1979-1980)
  Additional data is used from:
  • Vanguard 3 satellite (1959)
  • Alouette satellite (1962)
  • Woomera rocket (1964)
  • Cosmos 49 satellite (1964)
  • Dynamics Explorer satellites (DE 1 and 2 1981-1991)
  • Upper Atmosphere Research Satellite (UARS 1991-1994)
  • Polar Orbiting Geomagnetic Survey (POGS 1990-1993)
  Another high quality vector satellite mission will be conducted by the Danish:
  • Oersted (scheduled for launch in 1997)

• Aeromagnetic

  Airborne magnetic surveys have been conducted by many organizations around the world in specially designed aircraft. One notable survey called Project Magnet was carried out by the Naval Oceanographic Office in the United States starting in 1953.

• Marine

  Wooden ships were first used to survey the oceans starting in 1905. Towed scalar magnetometers were then used starting in the 1950's. The alternations in magnetic field direction found embedded in the sea floor (also known as magnetic striping) confirmed the theory of continental drift and sea floor spreading.

• Land Survey

  Portable magnetometers are used to supplement other surveys. A large number of surveys were conducted 1957 to 1969 as part of the World Magnetic Survey.

• Repeat Observations

  Repeat measurements are taken periodically at locations identified by a permanent marker. They are usually taken on a 3-5 year interval with a duration of 1-2 weeks.

Report of all data in the Goddard Space Flight Center library

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