The primary purpose of ACE is to determine and compare the isotopic and elemental composition of several distinct samples of matter, including the solar corona, the interplanetary medium, the local interstellar medium, and Galactic matter. Once in orbit, the four Cluster II spacecraft will spend two years passing in and out of our planet's magnetic field. Yohkoh Yohkoh, a Japanese satellite launched in 1992, uses a soft x-ray telescope to take dramatic pictures of the Sun. It just missed the last solar maximum, so the images it will give of the upcoming maximum should be exciting. The Wilcox Solar Observatory Located just west of Stanford University in California, the Wilcox Solar Observatory has studied the Sun since 1975, looking for connections between changes in the solar magnetic field and the space weather that affects Earth.
Researchers there have a special focus on the solar cycle.
Though the Solar Maximum Mission satellite has been out of service for ten years, it remains a pioneering mission in the field of solar science. It was launched in 1980 to study solar activity during the solar maximum and collected images and data for nine years. An archive of research papers published about the mission Information on SMM's instrumentation, with links to data Links to SMM instrument data archives Brought to you by the International Solar-Terrestrial Physics Program and NASA .