Mineral Composition on Mars and its Implications on Living Organisms

Research by: Sunil Stephenson, Rachelle Block, Mason Frith, Luis Combariza

Abstract

Many here on Earth have a desire to explore Mars in great depth, as it may be the best extra terrestrial body which humanity could colonize in the relatively near future. Colonization requires consideration of many factors to ensure the survival of any such attempt. This research focuses on the main integral factor which will determine long term success on Mars, the mineral content of the planetary surface. Our research aims to help show the unique mineral anatomy of Mars and to find potentially suitable regions for colonization on Mars. We performed research on many areas using a variety of sources and gathered data to understand how the mineral composition of Mar’s surface will influence the ease or difficulty of sustaining organic life.

Figure 1: Artist’s rendition of Mars colony living space. Image Credit: NASA, 2004. Website: https://www.nasa.gov/centers/ames/images/content/75997main_marshabitat.jpg

Introduction

Humans need food, water, and breathable air in order to survive. As climate change accelerates and resources on Earth deplete, scientists look to Mars as a potential option for colonization. This brings us to ask: is the mineral composition of Mars’ surface capable of sustaining organic life? Mars is a subject of high interest because many of its physical features resemble that of Earth. It also has many contrasting features. Despite these differences, and because of the similarities, the eventual goal is to physically reach and colonize Mars.

Figure 2: Artist rendering of what Mars future explorations and potential colonization may look like. Image Credit: NASA Ames Research Center (October 11, 2005). Website: https://www.nasa.gov/centers/ames/multimedia/images/2005/futureexploration.html

Mars has been a first candidate on many levels for new human habitation with the potential for long term settlement and growth, but how do we know that the needed nutrients are present on the surface of Mars? Due to the mineral composition that has been analyzed from data obtained via satellites and rovers, it has given us hope for exploration, survival and potential colonization of Mars. Understanding the mineral composition is powerful because with the right tools and knowledge we can harvest the essential materials we need without having to expensively and with great difficulty, continually transport these materials from Earth. The key limiting factor in reaching Mars is how much material we can transport including equipment, fuel, technology, and infrastructure.¹ Knowing what is available will allow us to be as efficient as possible with what we bring both initially, and once we are more established. Another factor is finding an effective way to transport the critical resources for survival, and compensating for different gravity, is to quickly establish what is needed for allowing mass production of technology and infrastructure on Mars it self to solve these issues. In understanding the mineral composition, scientists can discover how to produce food, and harvest water from Mars. According to Jordan’s article. ² The soil of Mars contains essential plant macro, and micro-nutrients. ³ However, not all locations will necessarily have the needed mineral content for terrestrial life, so we must have consideration for things such as which land is most ideal for Martian agriculture, considering both if it has the correct minerals, nutrients, access to water under the surface, and if not, if there are other areas near enough from which some of those necessary items could be transported.

So far what is known of Mars has been obtained by multiple space agencies, and there have been many studies done which include or focus on analysis of the Martian surface, mineral content, and evidence of water that is needed to sustain life. We will look into empirical evidence and data of the composition of Martian rocks, meteorites, and regional soil, which have been obtained using remote analysis. We have focused on multiple geographical areas for assessment of essential micro and macro nutrients, presence of water, as well any particular minerals that may be of use to the survival of living organisms. The composition of different areas may lead us to unique regions which may be superior to others making them potential landing and colonization sites.

Mars at a Glance

Mars is the fourth planet from the sun in our solar system. It is a unique planet with a red-brownish appearance in hue. The planet is one of the four known terrestrial in our system. The others are Mercury, Venus, and Earth. Mars has been a subject of great interest due to vast similarities in its land formation and topography. With further investigation from telescopic, satellite, and rover observations, scientists are coming closer to a global consensus that the planet Mars may be worthy as a candidate for human settlement and may lead to revamping our exploration of space .⁴ Why would we desire to leave our home world? The idea is not that we can, or want to shift everyone over to Mars, but to expand our influence, resources, and to find new and unique features about our universe. We are excited to learn as much about Mars as we can, and it is our hope that one day humans will be able to establish settlements on Mars. We also believe this will help us to advance our technological knowledge, advance our scientific methods, assist in improving space travel, help us find new efficient modes of energy generation, and eventually assist in reaching even more celestial bodies so to expand human presence and experience. With respect to the similarity of Mars and Earth, the following table ( adapted from Phoenix Mars Mission project led by Peter H. Smith from the University of Arizona), demonstrates the differences between the planets:

Planet Comparison	Mars Figure 3: NASA’s Earth-orbiting Hubble Space Telescope took the picture on June 26, when Mars was approximately 43 million miles (68 million km) from Earth. Credit: NASA and The Hubble Heritage Team (STScI/AURA). Acknowledgment: J. Bell (Cornell U.), P. James (U. Toledo), M. Wolff (SSI), A. Lubenow (STScI), J.Neubert (MIT/Cornell). Website: http://www.spacetelescope.org/images/opo0124a/	Earth Figure 4: On December 7, 1972, the crew of Apollo 17 changed the way we look at our home planet. This photograph illustrates the Earth as an isolated ecosystem, floating in space. (Astronaut photographs AS17-148-22727courtesy NASA Johnson Space Center Gateway to Astronaut Photography of Earth). Website: https://www.nasa.gov/multimedia/imagegallery/image_feature_329.html
Atmospheric Composition	Carbon dioxide: 98%, Nitrogen: 3%, Oxygen: 0.31%, Argon: 2%, Water Vapour: 0.03%, Nitric oxide: 0.01%	Nitrogen: 77%, Oxygen: 21%, Argon: 1%, Trace Gases: 1% which include Carbon dioxide 93.50%, Neon: 4.68%, Helium: 1.30%, Methane: 0.44%, Ozone: 0.01%, Nitrous oxide 0.08%
Atmospheric Pressure	7.5 millibars (average)	1,013 millibars (average)
Deepest Canyon	Valles Marineris: depth is 7 km and width is 4,000 km.	Grand Canyon: depth is 1.8 km and width is 400km
Distance from the Sun	227,936,637 km	149,597,891 km
Equatorial Radius	3,397 km	6,378 km
Gravity	3.71 m/s^2	9.81 m/s^2
Largest Volcano	Olympus Mons: height of 25.7 km and diameter of 602 km.	Mauno Loa: height of 10.1 km and diameter of 121 km.
Length of Day	24 hours and 37 minutes on average	Slightly less than 24 hours on average
Length of Year	687 Earth Days	365 Earth Days
Polar Ice Cap	Ice Caps are composed of carbon dioxide and water	Ice caps are composed of water
Average Surface Temperature	-63ºC	14ºC
Tilt of Axis	25º	23.4º
Number of Moons	2 Moons: Phobos and Deimos	1 Moon: The Moon

Table 1: Mars and Earth comparison and contrast at a glance. Data was adapted from the Phoenix Mission, which is led by Peter H. Smith of the University of Arizona. Supported by CO-investigators, NASA Jet Propulsion Laboratory, Lockheed Martin Space System and many international collaborators. Website: http://phoenix.lpl.arizona.edu/mars111.php

Of note from table 1, is that the composition of Mars’s atmosphere gives a little hope that life may be able to thrive. The composition of the atmospheric gases present is something that we need to overcome in order for humans and other organic life to safely thrive.⁵ In the figures below the atmospheric compositions are shown the pie graphs to help see the differences from a statistical stand point.

Figure 5: Schematic showing the atmospheric composition of A) Earth and B) Trace Gases of Earth in comparison to C) Mars. Image Credit: Sunil Stephenson.

Topography

Figure 6: These maps are global false-color topographic views of Mars at different orientations from the Mars Orbiter Laser Altimeter (MOLA). These data were compiled by the Mars Orbiter Laser Altimeter (MOLA) Team led by David Smith at the Goddard Space Flight Center in Greenbelt, MD. Image Credit: NASA Jet Propulsion Laboratory, California Institute of Technology. Website: https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA02820

A topographical map helps identify unique regions that may be potential candidates to find minerals that will support life. Scientists have developed a topographical device that allows us to have up to date topographical data that allows us to identify unique valleys, water systems, lake beds, and marinas (seas).⁶

Though Mars is roughly only half the diameter of Earth, its geographic features are incredible. Topography has been shaped by lava flows and meteorite impact craters. There is no permanent water on Mars and therefore, no “sea-level”. Rather than sea level, temperature and pressure data are assessed to map Mars. Mars’ highest point peaks at three times higher than Mount Everest at 27 km. The deepest crater is four times deeper and nine times longer than the Grand Canyon. Some surfaces are rocky and covered with dark stones while others are covered in dust and sand rich in iron oxide.

Although the aerography remains relatively the same, strong winds can blow the sand and dust to slightly change topography. The technique to helping achieve the topographical map of Mars was done by the Mars Observer Laser Altimeter (MOLA), which was one of the five instruments on the Mars Global Surveyor (MGS) space. It did this essentially by using laser as radar by firing it at the surface and measuring the time it took to bounce back to determine distance⁷. Thus upon data collection, it generates a color-coded image which describes the altimetry of the surface of Mars. This is demonstrated in the figure below, generated by the NASA MOLA team from the NASA Goddard Flight Center, which shows the altimetry of the surface, using colour to indicate the highest and lowest points(blue/cold being low, and red/warm colours being highest).

Figure 7: This image shows the Pole (north pole on left) to pole (south pole on right) view of Mars surface along the 0° longitude line that is from Smith et al (1999). Image Credit: MOLA Science Team. Website: https://tharsis.gsfc.nasa.gov/MOLA/index.php

From figure 7, it shows that there is 0.036 slope from pole to pole. This indicates that there is height difference of approximately 6 km. Thus it is reasoned that the North Pole is like a basin and the South Pole is a higher elevated zone.⁷ It is also noticed that the zones in between have unique river systems and pathways where it is speculated that water once flowed through and eventually led into the North pole which is a basin. This is important to help us identify where rich mineral deposit may be located and determine which are most feasible and accessible for us to extract resources for survival from. It may be possible to find unique zones and methods to identify what may have happened before Mars became completely barren. From understanding where the unique zones are in planet Mars, we are able to triangulate unique zones are regions that will be paramount in understanding what would be the best solution to colonizing Mars. But before we can occupy zones at random, we want to analyze the gross mineral composition by assessing the surface composition of Mars as was stated previously. This is relevant to helping us using, extracting and producing resources in house on Mars, instead of having to bring to much material from planet Earth in our early explorations and eventual colonization on Mars.

General surface Composition of Mars

There is no one particular mineral that dominates the Martian surface by a large degree in relation to the others, but there are a few rock/mineral types that make up the majority of the surface composition, each containing different elements and minerals. In a study of the global mineral distributions on Mars.⁸ The main Rock/mineral types looked for in this study were Feldspars (potassium and plagioclase) which made up roughly 12% and 16% of the overall composition of the surface respectively, pyroxenes (High in calcium and low in calcium) making up 12% and 2%, sheet silicates and high-Si glass, 8% to 10%, Olivine (none recorded), Sulphates in mostly equatorial regions (12% overall), Carbonates at 6%, (this amount was not detected by the method Bandfield covers) ⁷, and Quartz/amphibole which were not detected by Bandfield’s, but using measurements made by others he says that it does exist on the surface in few small concentrations making it roughly 1% overall. The remaining 29% of the surface is grouped under oxides (of which Hematite, an important iron oxide is a part). Most of these particular rocks/minerals are potentially important to a human future on Mars, this is because of the elements that they can contain, even more so as these particular findings are of what is at the surface. The surface of the planet will always, and especially early on, will be the most important as the resources there are much easier to access, and extract than anything which is located far below the ground.

Feldspar one of the more common surface materials on Mars, is used here on Earth for the making of glass, ceramics, fillers, enamel, glazes, and a lot more.⁹This mineral could be used eventually for similar things for any longer term missions on Mars, so that less need be brought along.

Figure 8: TES Geologic Map of Mars©. Geologic map of Mars showing hematite-rich zones in red. This image was based on spectroscopic measurements taken by the Mars Global Surveyor Thermal Emission Spectrometer..Image Credit: NASA/P. Christensen. Website: https://www.nasa.gov/multimedia/guidelines/index.html

The immediate uses of Pyroxenes appears to be low. Here on Earth it is often used as decorative stone, something likely not to be relevant to Mars explorers for some time to come, but pyroxene can contain elements in its make up such as magnesium, silicon, calcium, iron, sodium, oxygen¹⁰, depending on the exact type in question. If some of the elements found in pyroxene can be separated out of the rock, they could become practically (rather than decorative) useful to people on mars. Of special note, is many of the aforementioned elements are needed for human life in the form of essential dietary and trace minerals, in this case being; Magnesium, Calcium, Iron, Sodium. ¹¹ Being able to extract those and/or use them in soil with which planets will be grown for human consumption could be a useful way of ensuring a healthy diet with less reliance on supplements food, which would need to be transported from Earth. The mention of sheet silicates is interesting, as silica is used in many parts of the construction industry, such as in the making of glass, optical fibers, and communication components. ¹² Hematite (a form of iron oxide) is also present on the surface of Mars, in most areas according to data ⁸ ,hematite has not been found in concentrations higher than 5% in most areas.

However, an older NASA article,¹³ estimated that the iron oxide composition of Mars’s surface was in the range of 5% to 14%, also noting that iron could be used for the creation of power generation and transfer on Mars. Even though the overall level of iron oxides varies, there are a couple of areas of the surface of Mars which have much more concentrated deposits that have been discovered so far. ¹⁴ As is shown in figure 8. Also of note, the relatively high amounts of carbon dioxide present in what there is of Mars’s atmosphere could potentially be used to help humans extract specific minerals from the rocks on the surface of Mars. The carbon dioxide can potentially be used to make a supercritical fluid, which could be used to dissolve wanted elements away from others for our use on Mars.¹⁵

The specific example given in the article is that this supercritical fluid method could be used to dissolve magnesium, which can be used to fuel rockets, and because as noted above, it is likely there is magnesium to be found on Mars, it will be possible to use this specific minerals from Mars itself (like fuel). The article also notes that, usually on Earth we use other supercritical fluids (water) to dissolve things as it is relatively plentiful, but on Mars as there is much less available water than on earth, and a fair amount of carbon dioxide it would be much easier and economical to use carbon dioxide instead on Mars. It is also mentioned that this technique could be used to make water from rocks of Mars. As there are rocks, which if they contain hydrogen can be treated with this carbon dioxide to start a chemical process which can free the hydrogen from the rock, trap the carbon, and thereby have the hydrogen and the oxygen combine to make water.

We already have some capability to find these hydrogen bearing rocks for water as well, thanks to the Curiosity rover, it has tools, which can detect hydrogen, and it has found areas, which have such rocks.¹⁶

Thus from the data that has been provided from research and with our understanding of minerals, rocks and unique substances, this will be integral for building materials and generating ways to that are efficient, easy and maintainable ways for survival on a new environment. Thus knowing the topography and gross surface composition gives us the edge to becoming one step closer in having a successful colony on Mars. But furthermore, it will help us to expand our techniques in potential colonisations of other celestial. The next thing in concern for all life is its key source: water. We need to be able to develop a steady supply of water that will give us the edge to survive. Due to the fact that we can only transport water with a limit, we must be able to use the minerals and substances on the surface of Mars to help us develop a way to gain water to help meet the needs of humans and other organic life.

Water and Liquid on Mars

Figure 9: Comparison between Arizona’s Grand Canyon (a) on the left with the Nanedi Valles from Mars (b) on the right. From the image on right suggests the similarity of how the Colorado River on left cuts the Grand Canyon. Image Credit: NASA Jet Propulsion Laboratory. Web site: https://spaceplace.nasa.gov/mars-adventure2/sp/

Mars atmosphere is it too cold and the atmosphere is too thin to support liquid water on its surface. Theories suggest that Mars was once much warmer and wetter, with a thicker atmosphere. Therefore, Mars must have had a thicker atmosphere to support any water on the surface. A loss of atmosphere would have caused the water to evaporate. This led to carbon dioxide gas to react with elements in rocks and becoming locked up as carbonate ¹⁶. Earth has tectonic plates that release carbon dioxide, but Mars does not have tectonic plates. This could possibly be what led to Mars’ atmosphere depleting due to carbon dioxide being trapped within the rocks across the surface.¹⁷ Through the understanding of hydrated salts and ice deposits, we can explore the theories of water on Mars.

In 2015, NASA discovered recurring slope lines, the finding of hydrated salts. These hydrated salts are most likely a combination of calcium perchlorate, magnesium perchlorate, magnesium chlorate, and sodium perchlorate.¹⁸ Perchlorates have been shown to keep liquids from freezing even in extreme negative temperatures. Perchlorates do exist on Earth as naturally produced perchlorates are concentrated in deserts, and some types can be used as rocket fuel. This is the closest scientists have come to finding liquid water on Mars. Perchlorates are quite dangerous living organisms, meaning the water would need to be purified by removing the perchlorate salts from the water to be utilized for organic life. ¹⁹

In 2016, NASA discovered ice deposits beneath a region of cracked plain on Mars. There lies as much water as what is in Lake Superior. This deposit represents less than one percent of all known ice deposits on Mars. ²⁰

Understanding ice deposits and hydrated salts plays a large role in understanding the mineral composition of Mars. Water is obviously a necessity and need for humanity. Exploring ways to find essentials to humanity on Mars, such as drinkable of water, is crucial to the habitation of Mars.

Composition Based on Regions

Figure 10: Map of the regions of Mars with established names. Image Credited to: http://files.abovetopsecret.com/files/img/ot538fe447.gif

The surface of Mars has been mapped into geographical regions based on their varying altitudes, temperatures and mineral compositions. Most of the data obtained from satellite imaging and rover samples indicates that the mineral composition of Mars ranges based on location. Apart from Earth, Mars has the most altered surface of all planets and moons. ²¹

This is an important aspect of future colonization as organic life that is essential to human survival will be more prominent in some regions in comparison to others. Data from the Viking 1 mission which took place in the Kasei Valley points to fact that this planet has all the major mineral resources needed for to sustain a human colony. ²² It is widely accepted that one of the major constituents of the surface is Iron. The Viking missions proved that some of the iron-rich clay contains highly oxidizing substance that releases oxygen when precipitation is added. ²³ Oxygen is a key element for the survival of organic life. It’s possible ease of extraction could allow humans to harvest it for direct needs like respiration, for dietary needs or growing crops. The Maridiani Planum is a potential candidate as a land site for the Opportunity Rover because it it’s been understood through data analysis of orbital satellites that this area potentially contains minerals and elements (in unique forms such as) hematite, sulphates, chlorine and bromine.²⁴ Hematite is an important mineral to be considered because it is formed by the precipitation of water. Meaning that at some point this region could possibly have had liquid water. Bromide and chlorine are important elements when it comes to the purification and treatment of water and other industrial needs that could prove to be essential for organic life. Findings according to NASA about the composition of the environment in which the Pathfinder Rover landed (Tia Valley) indicate that some rocks appear to be high in silica. Silica has been found to improve drought tolerance and delay wilting in certain crops.²⁵ Mining such a mineral could prove to be essential for agricultural purposes. So what is the importance of looking at regional composition in Mars? Future colonization will have to be done in certain regions that facilitate human life as much as possible. Organic life needs certain chemical properties to survive. For this reason, regions like Terra Meridiani, whose mineral deposits and other elements essentials to humans could prove to be a colonization site due to its positive effect on organic.²⁶

Figure 11: Surface mineral composition based on location. Image Credited to: https://images.nature.com/full/nature-assets/nature/journal/v479/n7371/images/nature10582-f1.2.jpg

Conclusion

As we progressed through the, we desired to answer our selves if the mineral composition on Mars is capable for sustaining organic life? We have presented that there are unique regions that may be potential candidates for colonization due to its vast mineral content, but it also gives us hope that there may be more that Mars has to offer. The future goals are to improve our search and analyze the surface of Mars even more as we have presented. So that we can gain a understanding of the spectrum chemical and mineral composition and use that to our advantage so that we can comfortably establish the settlements and eventually grow on Mars From our work, we were able to present the possibilities of colonization but with important caveats to help us have the successful colonization we desire. From understanding topography, we are able determine using MOLA methods to help us triangulate unique regions that will be concentrated with minerals for resources to extract and from this and satellite and rover data, we are able to confer our results with topography to see if the areas such as Kasei Valley, Tia Valley and Maridiani Planum are unique places to establish settlement. We can use these methods to help us also find possible water sources such as the Nanedi Valley for potential water source. However, the important factor is knowing what is the surface composition in those unique areas and also looking into other regions so that we can use the resources to help build infrastructure, technology, settlements and methods of extraction to survive. From this we believe that this will help us to gain a foundation to explore other worlds in our solar system and beyond. Scientist are working on ground breaking ideas to utilize the surface Mars which are addressed in the videos, Could Humans Live on Mars (https://www.youtube.com/watch?v=Dzu8yXE4KNg) and Countour Crafting and building cities on Mars (https://www.youtube.com/watch?v=PVsMOcFn6zk) which emphasizes the importance of utilizing the mineral composition as a means of establishing life.

Figure 12: Three Generations of Rover technology Sojourner, MER and Curiosity. This image shows evolution of technology, which will be important for colonization in helping for exploration, settlement and extraction (January 17, 2017). Image: NASA/JPL-Caltech. Website: https://mars.jpl.nasa.gov/mer/gallery/press/opportunity/20120117a.html

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