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Density perturbations at the decoupling epoch produce angular fluctuations inthe temperature of the Cosmic Microwave Background (CMB) radiation that mayappear as hot and cold spots. Observational data of the CMB includesinstrumental noise in addition to the cosmological signal. One would like todetermine which of the observed spots are produced by the noise and whichcorrespond to signal. In this work we first present a statistical analysis ofthe first plus second year COBE/DMR map at 53 GHz that reveals the presence ofcosmological signal in the data. The analysis is based on Harrison-ZeldovichMonte Carlo realizations and utilizes a generalized $\chi^2$ statistic. Themethod is applied to the number of spots and the fraction of the total areathat appear above/below a certain value of the dispersion of the noise,including and excluding the quadrupole, giving $Q_{rms-PS}=15^{+3}_{-6}$,$18^{+5}_{-7} \mu K$ and $Q_{rms-PS}=18^{+3}_{-4}$, $21\pm6 \mu K$, at the$95\%$ confidence level, respectively. The data taken by the COBE/DMRexperiment during the first two years at three different frequencies (31, 53and 90 GHz) are used to determine which of the spots observed at 53 GHz appearsimultaneously in the other two channels. The significance of those spots isdetermined by comparison of their area and signal-to-noise with noise MonteCarlo simulations. We point out two cold spots and one hot spot at positions$(l,b)\approx (-99^{\circ},57^{\circ}),(-21^{\circ},-45^{\circ}),(-81^{\circ},-33^{\circ})$ respectively, at the $95 \%$ confidence level.Comment: uuencoded compressed postscript including figures. To be published in  Ap

Hot and Cold Spots in the First Plus Second Year COBE/DMR Maps