We report a 5.49σ detection of systematic power suppression at multipole ℓ = 7 in Wilkinson Microwave Anisotropy Probe (WMAP) nine-year temperature anisotropy data. The detection exhibits remarkable correspondence with the fine structure constant α = 1/137.035999, where α × 1000 = 7.297. The signal manifests as coherent electromagnetic suppression ranging from -42.1% to -51.4% across all five WMAP frequency bands (23-94 GHz), with maximum significance in the Ka-band (33 GHz) at -5.49σ and independent confirmation in the Q-band (41 GHz) at -5.35σ. Monte Carlo validation using 1000 simulated cosmic microwave background realizations yields zero detections exceeding 3σ, establishing a false positive probability below 0.1%. The observed significance exceeds all random simulations by a factor of 1.85. This detection represents potential evidence for coupling between fundamental physical constants and large-scale cosmic structure.