AbstractAn overview of the solar neutrino projects is given, with an emphasis on the complementarity of the different experiments (gallium, indium, heavy water,...) to solve the solar neutrino problem that was raised by the chlorine and the Kamiokande results. The separation of the different sources of neutrinos in the Sun would contribute significantly to the astrophysical understanding of the Sun. Some of the planned experiments could be able to pinpoint neutrino oscillations (within a wide range of parameters) almost independently of solar models. Projects which are particularly sensitive to a variation of the neutrino flux with time are also discussed.
Matter effects in active–sterile solar neutrino oscillations