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[en] Using the extrapolation of existing data, estimations of prompt-photon production at FAIR energies have been made. At y = yc.m. the rapidity density of prompt photons with pt > 1.5 GeV/c per central Au + Au event at 25 A GeV is estimated as ∼10-4. With the planned beam intensity 109 per second and 1% interaction probability, for 10% of most central events one can expect the prompt-photon rate ∼102 photons per second. Direct photons from the hadron scenario of ion collisions generated by the Hadron-String-Dynamics (HSD) transport approach with implemented meson scatterings πρ → πγ, ππ → ργ have been analyzed. Photons from short-living resonances (e.g., ω → π0γ) decaying during the dense phase of the collision should be considered as direct photons. They contribute significantly in the direct photon spectrum at pt = 0.5-1 GeV/c. At the FAIR energy 25 A GeV in Au + Au central collisions the HSD generator predicts, as a lower estimate, γdirect/γ (π0) ≅ 0.5% in the region pt = 0.5-1 GeV/c. At pt = 1.5-2 GeV/c γprompt/ γ (π0) ≅ 2%. Thermal direct photons have been evaluated with the Bjorken Hydro-Dynamics (BHD) model. The BHD spectra differ strongly from the HSD predictions. The direct-photon spectrum is very sensitive to the initial temperature parameter T0 of the model. The 10-MeV increase in the T0 value leads to ∼2 times higher photon yield.