The spacecraft is located in interstellar space part way to the sun (four times the distance of the moon from earth). It stays in a constant position that allows the combined gravity of the Earth and Sun to keep SOHO in an orbit locked to the Earth-Sun line. The mission was originally supposed to conclude in 1997. However, the equipment has continued working so the mission has been extended five times. The spacecraft was still sending images, video, and data, through 2012.
--Where is the solar wind produced and how is it accelerated?