Ørsted is Denmark's first satellite, named after Hans Christian Ørsted (1777–1851), a Danish physicist and professor at the University of Copenhagen, who discovered electromagnetism in 1820. Objectives The spacecraft primary science objectives were to perform highly accurate and sensitive measurements of the geomagnetic field and to perform global monitoring of the high energy charged particle environment. Instruments The instrumentation consisted of two magnetometers (proton precession and fluxgate), a star imager for attitude determination, a solid-state charged particle detector package, and a GPS receiver. The Science Instrument Team is responsible for the design of the instruments, while the Science Team is responsible for the science mission planning and international science participation. The science data obtained during the planned one-year mission will be used to derive an updated model of the geomagnetic field and its secular variation and to study the magnetospheric field-aligned currents and their relationship to ionospheric and solar wind conditions. The principal research topics are in two areas: 1° studies of the generation of the magnetic field in the fluid core and the magnetic and electrical properties of the solid Earth; and 2° studies of Earth's magnetic field as the controlling parameter of the magnetosphere and of all the physical processes that take place in the Earth's plasma environment, including phenomena like aurora and magnetic storms. The primary scientific instruments on the Ørsted satellite are: An Overhauser Effect Scalar Magnetometer provides extremely accurate measurements of the strength of the geomagnetic field. The Overhauser magnetometer is situated at the end of an 8 meter long boom, in order to minimize disturbances from the satellite's electrical systems. A Compact Spherical Coil (CSC) Fluxgate Vector Magnetometer, used to measure the strength and direction of the geomagnetic field. The magnetometer is situated somewhat closer to the satellite body in the so-called "gondola", together with: A star tracker developed by the Danish Space Research Institute, to determine the orientation of the satellite. The other three instruments are located in the main body of the satellite: The Charged Particle Detector, used to measure the flux of fast electrons, protons and alpha particles around the satellite. A Turbo-Rogue GPS receiver, the main use of the receiver is to accurately determine the position of the satellite. Periodically this instrument may also be used to investigate the atmospheric pressure, temperature, and humidity beneath the satellite. To utilize the Ørsted science data return, the plan is to establish an