Solar and Heliospheric Observatory (SOHO)

A scientific satellite launched by the European Space Agency on 2 December 1995 with an intended lifetime of two years. It was placed in orbit around the Sun at the point known as the L1 Lagrangian point, where the gravitational forces of the Earth and Sun are equal. Its twelve instruments were designed to investigate the solar atmosphere and how it is heated, solar oscillations, how the Sun expels material into space, the structure of the Sun and processes operating within it.