The albedo of the planet Mercury was measured at eight wavelengths from 584 to 1657 ¿ and at solar phase angles between 50¿ and 120¿. The geometric albedo varies from 4.1¿0.7% at 584 ¿ to 1.7¿0.5% at 1657 ¿. The albedo of the moon was measured at solar phase angle 75¿ for the same wavelengths, and the geometric albedo varies from 6.4¿1% at 584 ¿ to 2.2¿0.5% at 1657 ¿. The difference in albedo of the two objects may be due to the surface material or particle size or both; there are not sufficient experimental data at these short wavelengths to make a clear distinction.