Six different experiments were conducted on the Mars 2 and Mars 3 orbital spacecraft studying the Martian surface and lower atmosphere during and after a dust storm. Surface temperature, soil temperature, dielectric constant, relative altitudes at the planetary surface, surface brightness, H2O content, and the density of the lower atmospheric neutral gas and the electronic density of the ionosphere were determined. Instruments used included an infrared radiometer, radiotelescope, CO2 and H2O photometers, and a photometer in the 3700 to 6940 A range.