The partly Finnish-made SWAN instrument on board ESA-NASA Solar and Heliospheric Observatory (SOHO) is celebrating its twenty-fifth launch anniversary. Finnish Meteorological Institute (FMI) collaborated with the French Service d’Aeronomie in the scientific development of SWAN. In addition to FMI, VTT and Finnyards Oyj (now RUAG Space Finland) participated in constructing the instrument. SWAN has been in operation since December 1995. In addition to SWAN, also ERNE-instrument onboard SOHO is Finnish-made at the University of Turku.
SWAN is stationed 1.5 million kilometers closer to the Sun than the Earth, from where it observes the Sun and the edges of the Solar system. The observations are used to study slow changes in solar wind, i.e. the constant stream of electrically charged particles expelled from the Sun’s corona, and gases flowing in interstellar space.
“By utilizing the SWAN observations, it is possible to make an early warning about the dangerous space weather events even when the particle eruptions originate from behind the Sun. Now it is possible to get a warning 10 days before the shock hits the Earth compared to the earlier 3-day warning time” says Research Professor Ari-Matti Harri from FMI-SPACE.
Research Professor Ari-Matti Harri, firstname.lastname@example.org
Senior Research Scientist Terhi Mäkinen, email@example.com