The processes that drive the solar magnetic dynamo, the source of the Sun's magnetism, are hidden beneath the Sun's surface. The processes that dissipate the Sun's magnetic field and cause the 11-year solar cycle are not well understood either. By observing magnetic fields emerging from within the Sun in high detail and with great speed, Solar-B will help answer these questions.
Magnetic energy emerging from within the Sun heats the solar atmosphere, which in turn powers eruptions such as flares, spicules, and coronal mass ejections. These eruptions drive the solar wind -- a flow of electrically charged particles (plasma) and magnetic fields -- outward from the Sun at a million miles per hour or more, past the Earth and the other planets of the Solar System.
On Earth, disturbances in the solar wind can shock our planet's magnetic field and cause "geomagnetic storms." Such disturbances in Earth's magnetic field can energize spectacular auroras, cause communications interference, and induce overloads in electrical power grids and equipment.
Solar-B will observe the source of the solar wind and the disturbances it creates. These detailed observations will help us better understand this crucial Sun-Earth connection.
Small variations in the Sun's energy output can change weather and climate on Earth. During the 17th century, an abnormal period of low solar activity conincided with the "Little Ice Age" in northern Europe. Observations from space have shown that the total energy output of the Sun changes with variations in its magnetic cycle.
Solar-B will continuously monitor the buildup of sunspots as well as extremely small-scale magnetic structures as the Sun heads toward the next peak in its activity cycle.
Radiation pours from the Sun. Its super-heated chromosphere and corona are powerful, highly variable sources of ultraviolet and X-ray radiation. Solar flare explosions produce intense bursts of gamma radiation and blasts of energetic particles. All of this high-energy activity affects Earth's ionosphere, ozone layer, and environment.
Solar-B will study magnetic reconnection and wave dissipation in the chromosphere and corona -- processes that are believed to convert solar magnetic energy into ultraviolet and X-ray radiation.