i) studying the solar interior using helioseismology,
ii) monitoring of the characteristics of solar wind particles in-situ,
iii) monitoring anisotropies in the solar wind through the imaging of Lyman-alpha light,
iv) studying the nature of the white light and UV high corona using coronagraphs,
v) studying the structure and evolution of the low corona by imaging the EUV Sun, and
vi) studying the nature of the low corona through spectroscopy in the UV and EUV.
The instruments are listed in Table 1.
| Instrument/Experiment | Principal Investigator | Description |
| GOLF (Global Oscillations at Low Frequencies) | A. H. Gabriel, Paris, France | Global Sun velocity and magnetic field measurements |
| VIRGO (Variability of Solar Irradiance) | C. Frölich, Davos, Switzerland | Global and low resolution imaging of oscillations and solar constant |
| MDI (Michelson Doppler Imager) | P. H. Scherrer, Stanford, USA | High resolution imaging of velocity oscillations |
| SUMER (Solar UV Measurement of Emitted Radiation) | K. Wilhelm, Lindau, Germany | Plasma flows, temperature and density in solar atmosphere |
| CDS (Coronal Diagnostic Spectrometer) | R. A. Harrison, Chilton, UK | Density, temperature and flows in the solar atmosphere |
| EIT (EUV Imaging Telescope) | J.-P. Delaboudinière, Paris, France | Evolution of low coronal structure and activity |
| UVCS (UV Coronagraph Spectrometer) | J. L. Kohl, Cambridge, USA | Densities and temperature in corona |
| LASCO (Large Angle Spectrometer Coronagraph) | G. Brückner, Washington, USA | Structure and evolution of the corona |
| SWAN (Solar Wind Anisotropies) | J. L. Bertaux, Paris, France | Solar wind mass flux anisotropies |
| CELIAS (Charge, Element, Isotope Analysis) | D. Hovestadt, Garching, Germany | Ion composition of the solar wind |
| COSTEP (Suprathermal and Energetic Particle Analyser) | H. Kunow, Kiel, Germany | Ion and electron composition in solar wind |
| ERNE (Energetic Particle Analyser) | J. J. Torsti, Turku, Finland | Ion and electron composition in solar wind |
Table 1: the SOHO instrument payload.
