Status of solar neutrino observations and prospects for future experiments

For the past twenty years, an experiment in the Homestake Gold Mine in Lead, South Dakota, has been engaged in the measurement of the neutrino flux emitted by fusion reactions in the core of the sun. Within the past two years, a second detector, located at Kamioka, Japan, has also observed these neutrinos and has verified the Homestake neutrino flux measurements. Therefore, it has now been experimentally demonstrated that fusion reactions indeed occur in the sun. The observed flux is a factor of three to four smaller than that predicted by the standard solar model (SSM). In this report the author presents the results of the present experiments, describes several new experiments that should be operational within the coming year or so, and discusses suggestions for the difference between the observed and predicted solar neutrino fluxes