ocr: - 9 D r Composition of the Martian soil: MARS: GENERAL INFORMATION Oxygen: 50% AMSS SATELLIIES Silicone: 20% Iron: 14% Magnesium: 4% Sulfur: 3.7% Calcium: 3.7% Aluminum: 3.5% litanium: 0.4% Certain areas show concentrations of phosphorus (up to 10%), manganese (7%), and chlorine (3%). Mars has a low atmospheric pressure, similar to that inside a plane at cruising speed. Viking 1 measured Martian atmospheric pressure at an average 7.6 millibars. (This low pressure explains the absence of liquid water on Mars: when ice on the planet warms, it is "sublimed" or undergoes sublimation, - meaning it ...
