Ulysses

The ULYSSES probe is a joint ESA and NASA mission, devoted to the in situ study of turbulence in the solar wind, especially outside the ecliptic plane. Its instruments were designed and manufactured by European and American scientists. Several European laboratories took part in the development of Ulysses. The ULYSSES probe was launched on board the space shuttle Discovery from Cape Canaveral, USA, on 6 October 1990.

The Ulysses probe
(Credits: ESA)

The objective of the ULYSSES is to:

• Determine the overall three-dimensional properties of the heliospheric magnetic field and the solar wind;
• study the origins of solar wind by measuring its composition at different heliographic latitudes;
• increase our knowledge of shock waves in the solar wind by sampling the conditions from those measured near to the ecliptic;
• increase our knowledge of processes affecting the movement of abnormal and galactic cosmic rays;

• increase our knowledge of the origin of galactic cosmic rays by measuring their isotopic composition;
• study the energy level and movement of the energetic particles of solar and interplanetary origin by observing their properties at low and high latitudes;
• learn more about nearby interstellar space medium by direct measurements of the neutral helium atoms that enter the heliosphere, as well as by deducing their properties from measurements of interstellar ions;
• improve our knowledge about interplanetary and interstellar dust;
• search for sources of gamma bursts and, using simultaneous observations from other satellites, help to identify them in relation to known celestial objects.

The ULYSSES probe is equipped with twelve instruments:

• VHM/FGM: The Vector Helium Magnetometer / Flux Gate Magnetometer; the French CETP (Centre d'Etude des Environnements Terrestre et Planetaires) participated in this project;
• SWOOPS (Solar Wind Plasma experiment): a solar wind plasma experiment, the CETP participated;


• SWICS (Solar Wind Ion Composition Instrument);


• URAP (Unified Radio and Plasma Wave instrument): an experiment to measure radio waves and plasma in the inner heliosphere, carried out jointly by 4 laboratories: the NASA/GSFC Laboratory for Extraterrestrial Physics (LEP), the Paris Observatory LESIA, the University of Minnesota and the CETP at Vélizy;


• EPAC (Energetic Particle Instrument);


• GAS (Interstellar Neutral-Gas Experiment);


• HISCALE (Low-energy Ion and Electron Experiment) in which the LESIA also participated;


• COSPIN (Cosmic Ray and Solar Particle Instrument)

GRB (Solar X-ray and Cosmic Gamma-Ray Burst Instrument);

• DUST (Dust Experiment) ;


• SCE (Coronal-Sounding Experiment);


• GWE (Gravitational Wave Experiment).