SOlar and Heliospheric Observatory
SOHO studies the internal structure of the Sun, its extensive outer atmosphere and the origin of the solar wind, the stream of highly ionized gas that blows continuously outward through the Solar System. SOHO helps to understand the interactions between the Sun and the Earth's environment, the Sun itself including the heating of the solar corona, the acceleration of the solar wind, and the physical conditions of the solar interior.
That view of the Sun is achieved by operating SOHO from a permanent vantage point 1.5 million kilometers ahead of the Earth in a halo orbit around the L1 Lagrangian point.
Instrument for satellite
CELIAS (Charge, Element, and Isotope Analysis System) is the instrument on board SOHO where MPE is involved most.
Launch: December 2, 1995
actual status: active; in orbit around L1
end of mission: extended until 2020