Solar and Heliospheric Observatory

SOHO

Mission Profile

SOHO (Solar and Heliospheric Observatory) is a joint ESA/NASA spacecraft launched on 2 December 1995 aboard an Atlas IIAS to the Sun-Earth L1 Lagrange point, where it has continuously monitored the Sun for over three decades. Carrying twelve scientific instruments, SOHO studies the Sun's interior through helioseismology, its corona through coronagraphs, and the solar wind from the Sun's surface out to well beyond Earth's orbit. An unexpected benefit has been SOHO's status as the most prolific discoverer of comets in history, with citizen scientists using its LASCO coronagraph images identifying over 4,000 sun-grazing comets. Despite a near-fatal loss of attitude control in 1998 that temporarily disabled the spacecraft, SOHO was successfully recovered and continues to provide real-time solar monitoring critical for space weather forecasting.