Whole-Disk Observations of Jupiter, Saturn, and Mars in Millimeter/Submillimeter Bands

New balloon-borne observations of whole-disk brightness ratios for Jupiter, Saturn, and Mars are reported in four millimeter/submillimeter bands of bandwidth Δν ≈ 1-2 cm-1. Using the effective planetary radii of Hildebrand et al., we find that TMars/TJupiter=1.158 ± 0.015, 1.189 ± 0.015, 1.470 ± 0.019, and 1.515 ± 0.019 and TSaturn/TJupiter=0.833 ± 0.012, 0.758 ± 0.010, 0.818 ± 0.012, and 0.840 ± 0.012, at ν=5.7, 9.5, 16.5, and 22.5 cm-1, respectively. Using models for the brightness temperature of Mars, we also give the whole-disk brightness temperatures for Jupiter and Saturn for the four frequencies.