Experimental data, obtained when searching neutrino radiation from gravitational collapse of stars are discussed. The following reactions are used for neutrino detection in experiments: ..nu..-tilde/sub e/+p->n+e/sup +/ and ..nu..+e/sup -/->..nu..+e/sup -/. Characteristics of four detectors, used during flare of Supernovae star on February, 23, 1987: Baksan underground scintillation telescope, Soviet-Italian liquid scintillation detector LSD, Cherenkov detector K2 (Japan-USA) and Cherenkov detector IMB(USA). Analysis of experiments showed that effects in each of four detectors satisfied or at least didn't disagree with conditions of mentioned reaction detection. Many problems should be solved when interpreting the whole body of results of neutrino detectors: two-stage mechanism of collapse, different angular distributions of K2 and IBM etc. The main problem lies in the fact, that measured enrgy fluxes in neutrino radiation exceed many times the same ones, permissible from the view point of modern astrophysical concepts.