The spiral galaxy NGC 3370 hosts two critical standard candles in extragalactic astronomy: Cepheid variable stars and Type Ia supernovae. The intrinsic luminosity of Cepheid variables is determined via the well-established period–luminosity relation, wherein pulsation period correlates directly with absolute magnitude. Type Ia supernovae exhibit a standardized peak luminosity due to their origin in carbon–oxygen white dwarf detonations near the Chandrasekhar limit. By comparing observed apparent