Аннотация:We give an overview of the SPHERE experiment based on detection of reflected Vavilov-
Cherenkov radiation (”Cherenkov light”) from extensive air showers in the energy region
E>1015 eV. A brief history of the reflected Cherenkov light technique is given; the observations carried out with the SPHERE-2 detector are summarized; the methods of the
experimental datasample analysis are described. The first results on the primary cosmic
ray all-nuclei energy spectrum and mass composition are presented. Finally, the prospects
of the SPHERE experiment and the reflected Cherenkov light technique are given.