The Martian Environment:
Some general understanding of the Planet is necessary before we begin the survey. The first is atmosphere and weather. The atmosphere of Mars consists of about 95% carbon dioxide, 3% nitrogen, 1.6% argon and contains traces of oxygen and water. The atmosphere is quite dusty, containing particulates about 1.5 µm in diameter, which give the Martian sky a tawny color when seen from the surface. Methane has been detected in the Martian atmosphere with a mole fraction of about 30 ppb; it occurs in extended plumes, and the profiles imply that the methane is released from discrete regions. In northern midsummer, the principal plume contained 19,000 metric tons of methane, with estimated source strength of 0.6 kilogram per second. It stays anywhere from 4-.05 years in the atmosphere before being destroyed by solar radiation. Mars has no ozone layer in its atmosphere. This rapid turnover would indicate an active source of the gas on the planet. Volcanic activity, cometary impacts, and the presence of methanogenic microbial life forms are among possible sources. Methane could also be produced by a non-biological process called serpentinization involving water, carbon dioxide, and the mineral olivine, which is known to be common on Mars. Olivine hides out in what geochemists call ultramafic rock—rock high in magnesium- and iron-containing olivine and pyroxenes, which are silicate minerals. During serpentinization, water attacks olivine and alters it to another mineral, called serpentine. At the same time, the hydrogen molecules are cleaved from the water. In the presence of certain catalysts, those hydrogen molecules combine with the carbon to form carbon dioxide and to form methane (CH4). For the reaction to occur, the water must not be frozen, so serpentinization could not take place on the surface of Mars which makes sense. Since water on the surface due to the atmospheric pressure would evaporate immediately upon exposure. This was how the water/ice was discovered in the Phoenix Mission.
Ice found at Phoenix Mission dig
The atmosphere that once enshrouded the planet is gone because Mars has almost no magnetosphere, which was in turn produced by a geological dynamo that probably just barely works at present. Most of the atmosphere is heaviest at high magnetic locations on the planet’s surface.
Mars Plate Tectonics and Surface Magnetism
Right now NASA is in the process of launching the Maven Mission that will study the planet’s atmosphere and weather. However, robots cannot do it all. What stops a manned mission is money. It takes an investment to develop systems that will service and deliver the explorers to the planet that is more expensive in some minds than a robotic mission is. Of all the planets in the Solar System, the seasons of Mars are the most Earth-like, due to the similar tilts of the two planets' rotational axes. The lengths of the Martian seasons are about twice those of Earth's, as Mars's greater distance from the Sun leads to the Martian year being about two Earth years long. Martian surface temperatures vary from lows of about −143 °C (−225 °F) (at the winter polar caps) to highs of up to 35 °C (95 °F) (in equatorial summer). The wide range in temperatures is due to the thin atmosphere, which cannot store much solar heat, the low atmospheric pressure, and the low thermal inertia of Martian soil. Mars also has the largest dust storms in the Solar System. These can vary from a storm over a small area, to gigantic storms that cover the entire planet.
A Mars Global Dust Storm
They tend to occur when Mars is closest to the Sun. Dust storms have been shown to increase the global temperature. The tectonic activity of the planet is very small. The planet has cooled down inside as well as not being able to maintain an atmosphere that can retain a warmer temperature. This I believe is due two things. The first is the planet’s distance from the sun and the second is the small size of the planet. This is what I believe has had a great affect on the planet’s tectonic activity. The core may still be hot but not strong enough to force a magma eruption through the mantle and then the crust. The tectonic plates of the Mars, do not act like the ones we have on Earth. It has been a very long time since there has been any volcanic activity on the planet. When the planet was active, there was a catastrophic geological event that occurred as evidenced by the closeness of the Tharsis Bulge to the Valles Marineris. For the latter part of the Planet’s volcanic history the planet used the same passages for volcano eruptions in the Tharsis Bulge and Mons Olympus, which is why their peaks are at the highest altitudes known in the solar system. This would have happened when movement of the tectonic plates ceased. However, I think there is evidence that these tectonic plates are still moving but very slowly.
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