Location and Orbit
Atmosphere and Magnetosphere
Missions to Mars
References & Links
Life on Mars?
Mars: Atmosphere and Magnetosphere
The Hubble Space Telescope has allowed scientists to study the planet's atmosphere and weather conditions. Winds are not foreign to the planet, ranging from 7.0 km/h to 80 km/h during heavy dust storms. These yellowish storms usually originate in the southern hemisphere and have the consistency of flour.
The Martian atmosphere is composed of several types of gases, the most abundant of which being carbon dioxide (95.32%). Nitrogen (2.7%), argon (1.6%), oxygen (0.13%), carbon monoxide (0.07%), and water vapor (0.03%) bring up the rear. Traces of other molecules also exist: neon, krypton, xenon, and ozone. The atmospheric pressure ranges from 6 to 10 millibars, varying with time and place.
Six major kinds of clouds are found on the planet. One noted authority, Shafer states that "the polar hood is a haze of water and perhaps carbon dioxide ice that forms over the polar regions in the fall and can cover much of the northern plains. Wave clouds form on the sheltered side of large obstacles, such as craters, and have very distinct ridges. Convective clouds form in high areas at midday. Orographic clouds form when air lifts over large-scale objects like Olympus Mons and are most common in spring and summer when the water vapor content of the air is highest. Ground hazes occur in low areas at dawn and dusk and probably consist of water ice. Wispy high-altitude clouds sometimes occur just at dawn and dusk. The Viking 2 lander recorded images of water-ice frost during the winter."
Mars has a very weak magnetic field, although it may have been stronger in the past. As the planet solidified, however, the magnetic field weakened.
Copyright © 2000 by Gary Chan and Matthew McDermott. All rights reserved.