Water and Potential Life on Mars, By Drew Price

Mars has been thought to have been cold, dry, and dead for billions of years. Mars’ past, however, reveals a much warmer climate with flowing rivers, even though its atmosphere today is too thin, allowing water to freeze or ultraviolet light to penetrate to the surface and boil it away as Hydrogen and Oxygen. There is evidence supporting this past, such as dry river beds and minerals on the surface that form in the presence of water. Additionally, recent observations and research reveal that Mars is not yet dead, but still active. There have been abundant methane emissions in the Martian atmosphere throughout the last several Mars years. By using telescopes with spectrometers, analysts have detected three areas where substantial amounts of methane have been absorbing reflected sunlight from Mars’ surface. These observations show that there are ongoing processes that release methane, especially because Mars’ thin atmosphere normally destroys it quickly. These processes can be attributed to one or both of the following: ongoing geological processes and microbial processes.
The geological approach claims that methane plumes are released due to geological processes similar to those on Earth. Mars does not have any currently known, active volcanoes. The possibility still exists, however. Thus, methane may be released through volcanic out-gassing. In this case, ground water, carbon dioxide, and Mars’ internal heat all factor together to create methane. Then, the methane can travel to the surface and be released through volcanic activities. However, other processes may be factors. The methane plumes observed are most substantial during the warm season and seem to cover areas where there is evidence of ancient ground ice or flowing water. Therefore, another possibility is that methane (similarly formed) is stored in ice “cages” under the surface. During the warm season, permafrost situated over fissures is heated. As the permafrost clears, stored methane can be released into the atmosphere through the openings fissures provide. Additionally, the surface above these ice “cages” may happen to be the areas where there is evidence for ancient ground ice or flowing water. From observations, some methane plumes also contained water vapor, supporting this claim. This fact, however, leads to the microbial approach on the methane emissions.
The microbial approach claims that many biological organisms release methane as they digest nutrients. On earth, microorganisms can thrive two to three kilometers beneath the surface where radiation can split water into Hydrogen and Oxygen. The microorganisms then use the Hydrogen for energy. Similarly, it is possible that there is subsurface liquid water under the Martian tundra. Microorganisms can then use the Hydrogen, split from water through radiation, in addition to subsurface carbon dioxide to thrive. The methane they release through digestion could be stored under the surface until fissures or volcanic out-gassing allows it to be released into the atmosphere. In addition, with such large amounts being released, these microbial processes may have been occurring for the past billions of years. Knowing that some of Earth’s earliest life forms created methane through carbon dioxide and Hydrogen, there is the potential for the beginnings of life on Mars as well.
Subsurface liquid water is essential for either of the two processes. There is some evidence pointing to the existence of some form of water on Mars, meaning that liquid water below the surface is quite reasonable. As stated before, there has been water vapor discovered in some of the methane plumes, suggesting subsurface water. In 1997, an image from a Mars Global Surveyor showed evidence of seepage features on the walls of a crater. The material in the crater’s gully could just be lava flows, but there is the possibility that the gullies hold ice water instead. Upwelling subsurface water would be a significant factor for potential life on Mars. The water would continually replenish the surface ice, and if the water held organic material or even microorganisms, there would be direct evidence for life in the ice. Then, drilling could be done well in advance of human missions in order to further the promotion of life on Mars. In addition, NASA’s Phoenix Lander has also identified water in a soil sample. There was evidence for ice water by earlier orbiters, as well as by the Phoenix while it was in orbit. However, the Phoenix was also able to land and take a soil sample that was two inches deep. The soil was frozen hard, but the Phoenix was able to warm up the sample and taste liquid water in it. The ice sample does create questions about the ice being able to thaw enough or hold the proper carbon-containing chemicals to support life, but it allows for a greater understanding of the Martian soil for future missions as well.
From the data on methane emissions to the data regarding water on Mars, one can believe that Mars is still active. Although the extent of this activity – whether geological, biological, or both – is unknown, these observations add to the knowledge of Mars. As time progresses, new technologies, discoveries, and missions will continue to enhance this understanding. Whatever the future will reveal, time will only tell!


Sources:

Bridges, Andrew. “NASA Announces Discovery of Evidence of Water on Mars.” Space.com. 2000. 23 March 2009 .

Hammond, Sara, and G. Webster. “Phoenix Mars Lander: Exploring the Arctic Plain of Mars.” NASA.gov. 2008. 23 March 2009 .

Steigerwald, Bill. “Martian Methane Reveals the Red Planet is not a Dead Planet.” NASA.gov. 2009. 23 March 2009 .