Is It Possible to Create a Viable Atmosphere on Mars?

Is it possible to create a viable atmosphere on Mars?

Is it possible to create a viable atmosphere on Mars?

Check out this answer from Consensus:

While the creation of a viable atmosphere on Mars presents numerous challenges, research suggests that there are several potential methods to achieve this goal. From plasma technology and photosynthesis to innovative materials like silica aerogel and large-scale engineering projects, scientists are exploring a variety of approaches. Each method has its own set of challenges and timeframes, but the collective research indicates that the dream of a habitable Mars is not beyond the realm of possibility.

 

The prospect of colonizing Mars has captivated the imagination of scientists, engineers, and the general public alike. A key challenge in this endeavor is the creation of a viable atmosphere that can support human life. This article explores various concepts and research findings related to the feasibility of engineering Mars’ atmosphere to make it habitable for future colonists.

Plasma Technology for Oxygen Production

One innovative approach to producing oxygen on Mars involves plasma technology. Researchers have proposed using plasma to split the Martian atmosphere, which is predominantly carbon dioxide (96%), into breathable oxygen and carbon monoxide, which could serve as a fuel source. This method is particularly promising due to the ease of splitting carbon dioxide into oxygen on Mars compared to Earth1.

Photosynthetic Oxygen Production

The generation of oxygen through photosynthesis has been considered a viable method for atmospheric engineering on Mars. The process would rely on the growth of photosynthetic microorganisms, utilizing the available water, carbon dioxide, and mineral nutrients on the Martian surface. However, this method would require a significant increase in the planet’s average temperature and atmospheric mass, and it is estimated that the conversion of the Martian atmosphere to one containing oxygen could take many thousands of years2.

Terraforming Mars Quickly

A more rapid terraforming process has been proposed, which involves using a solar mirror to vaporize parts of the Martian regolith, releasing trapped volatiles such as oxygen, nitrogen, carbon dioxide, and water vapor. The breathable atmosphere could then be completed by photosynthesis, potentially speeding up the terraforming process3.

Silica Aerogel for Habitability

An alternative approach to making Mars habitable involves the use of silica aerogel. This material could create a solid-state greenhouse effect on the Martian surface, allowing for the transmission of visible light for photosynthesis, blocking harmful ultraviolet radiation, and raising temperatures to above the melting point of water. This method could enable photosynthetic life to survive on Mars with minimal intervention and is considered more achievable than global atmospheric modification4.

Economic Analysis of Martian Settlements

The economic aspects of constructing sustainable open-air human settlements on Mars have also been studied. Considering the harsh conditions on the Martian surface, the possibility of building settlements with a direct connection to the Martian atmosphere has been explored. This would involve excavating deep into the Martian crust to reach air pressures sufficient for human survival without pressurized suits. The feasibility, benefits, and difficulties of such an undertaking have been analyzed, highlighting the economic considerations of creating a habitable environment on Mars5.

 

Is it possible to create a viable atmosphere on Mars?

Chris McKay has answered Likely

An expert from The National Aeronautics and Space Administration in Geophysics, Atmospheric Science

One sentence answer: It is possible to create an atmosphere on Mars that is suitable for life but not with high enough O2 for humans to breath.

Short full answer:

Terraforming Mars can be divided into two phases. The first phase is warming the planet from the present average surface temperature of -60ºC to a value close to Earth’s average temperature to +15ºC, and re-creating a thick CO2 atmosphere. This warming phase is relatively easy and quick, and could take about 100 years. The second phase is producing levels of O2 in the atmosphere that would allow humans and other large mammals to breath normally. This oxygenation phase is relatively difficult and would take 100,000 years or more, unless one postulates a technology breakthrough.

References:

Marinova, M. M., McKay, C. P., & Hashimoto, H. (2005). Radiative‐convective model of warming Mars with artificial greenhouse gases. Journal of Geophysical Research: Planets (1991–2012), 110(E3).

McKay, C.P., Toon, O.B. and Kasting, J.F., 1991. Making Mars habitable. Nature, 352(6335), p.489.

Rest of the answer if a long answer is of interest:

Before any terraforming begins, there are a series of basic questions that must be addressed by robotic and human missions to Mars. These are

  1.       The amount of H2O present on Mars.
  2.       The amount of CO2 present on Mars as gas, as ice, or absorbed on soil.
  3.       The amount of nitrate in the soil on Mars.
  4.       The presence of life, alive or revivable, and the relationship of that life to Earth life

These are the questions about Mars that require answers in order to plan any terraforming effort. However there is also a fundamental question about terraforming itself that we must answer on Earth before terraforming begins

  1.       What is the purpose and ethical approach for making Mars habitability.

It may be impossible to arrive at a unanimous and definitive answer to question 5 but at the least we need an operational consensus.

Adequate inventories of water, carbonere on that planet. We know that Mars has enough H2O to supply clouds in the sky, rain, rivers and lakes. Presently, this H2O is mostly in the form of ice in the polar regions and polar caps but once Mars is warmed this will melt. Carbon dioxide is needed to provide a thick atmosphere to contribute to the warming and which will constitute the thick atmosphere at the end of the warming phase. While CO2 may be present on Mars in vast quantities tied up in carbonate minerals, this form is not easily released as gas in the warming phase. Only the CO2 that is easily released as gas as the temperature increases will contribute to the atmosphere during the warming phase. This includes the small amount of CO2 in the present atmosphere, the CO2 that is contained in the polar caps, particularly the winter South Polar Cap, and any CO2 that is absorbed into the cold ground in the polar regions. Once the warming starts all this releasable CO2 will go into the atmosphere. Thus, it is important to know the total before warming starts. Current estimates of the releasable CO2 on Mars today range from a little more than the present thin atmosphere to values sufficient to create a pressure on Mars equal to the sea level pressure on Earth. Nitrogen is a fundamental requirement for life and necessary constituent of a breathable atmosphere. The recent discovery by the Curiosity Rover of nitrate in the soil on Mars (~0.03% by mass) is therefore encouraging for terraforming. The current measurements only pertain to surface samples at the Curiosity site but include windblown sand and ancient sedimentary mudstones. For terraforming we need to know the total amount on the planet and given nitrates high solubility is may well be concentrated in specific locations.

In addition to water, carbon dioxide, and nitrogen, terraforming Mars may require the element fluorine for the production of super greenhouse gases. Curiosity has recently confirmed the presence of fluorine in the rocks on Mars – which was expected based on the presence of fluorine in the meteorites from Mars.

The presence and nature of life on Mars will definitely affect plans for terraforming. If there is no life on Mars then the situation is relatively straightforward. However, even after extensive exploration it may be hard to conclude that life is completely absent on Mars rather than simply not present at the specific locations investigated. If life is discovered then the nature relationship between the Martian life and Earth life must be determined. If Martian life is related to Earth life – possibly due to meteorite exchange, then the situation is familiar and issues of what other types of Earth like to introduce and when must be addressed. However if Martian life in unrelated to Earth life and clearly represents a second genesis of life then significant technical and ethical issues are raised.

The question of possible Martian life leads to the fifth question that must be addressed before terraforming begins. This is the question of why, and for who whom, are we altering Mars? If we are determined to make Mars like the present Earth – as implied in the work “terraforming” then this requires certain levels of O2 and places upper limits on toxic gases such as CO2. Alternatively, if we are interested in making Mars a planet rich in life, but not necessarily a world in which humans can move about unprotected, then the presence of a thick CO2 may be an adequate goal.

Warming Phase: 100 years

The primary challenge to making Mars a world suitable for life is warming that planet and creating a thick atmosphere. A thick warm atmosphere would allow liquid water to be present and life could begin. Warming an entire plant may seem like a concept from the pages of science fiction but in fact we are demonstrating this capability on Earth now. By increasing the CO2 content of the Earth’s atmosphere and the addition of supergreenhouse gases we are causing a warming on Earth that is of order a many degrees centigrade per century. Precisely these same effects could be used to warm Mars.

Warming the Earth was not the intended purpose of either the CO2 release or the use of supergreenhouse gases by humans and indeed we are now seeking to limit both effects. On Mars we could purposefully produce supergreenhouse gases and rely on CO2 released from the polar caps and absorbed in the ground. The result would be a thick warm atmosphere on Mars.

As we might expect from noting that on Earth warming of several degrees per century is occurring without a focused effort, the timescale for warming Mars after a focused effort of supergreenhouse gas production is short, only 100 yrs or so. Effectively greenhouse gases warm Mars by trapping solar energy. If all the solar incident on Mars were to be captured with 100% efficiency then Mars would warm to Earth-like temperatures in about 10 years. However the efficiency of the greenhouse effect is not 100% and is plausibly about 10%, thus the time it would take to warm Mars would be 100 years. This assumes of course adequate production of supergreenhouse gases over that entire time.

The supergreenhouse gases desired for use on Mars would be perfluorinated compounds (PFCs) as these are not toxic, do not destroy ozone, a long lifetime on Mars against destruction by ultraviolet life, and are composed of elements (C, S, and F) that are present on Mars.

The Warming Phase on Mars results in a planet with a thick CO2 atmosphere. The thickness is determined by the total releasable CO2 present on Mars. The temperatures are well above freezing and liquid water is common. An Earth-like hydrological cycle is maintained. Photosynthetic organisms can be introduced (Table 1) as conditions warm and organic biomass is thus produced. A rich flora and fauna are present. A natural result of this is the biological consumption of the nitrate and perchlorate in the Martian soil producing N2 and O2 gas. While the pressure is high enough that humans do not need a space suit, they need a gas mask to provide O2 and prevent high levels of CO2 in the lungs.

Oxygenation Phase: 100,000 years

To alter the thick CO2 atmosphere of Mars produced in the Warming Phase to allow for humans to breathe naturally requires that the O2 levels be above 13% and the CO2 levels be below 1% of sea level pressure. The high O2 and low CO2 levels on Earth are due to photosynthesis which uses light to power the following transformation:

H2O + CO2 = CH2O + O2 Where CH2O is a chemical representation of biomass. If all the sunlight incident on Mars was harnessed with 100% efficiency to perform this chemical transformation it would take only 17 years to produce high levels of O2.

However, the likely efficiency of any process that can transform H2O and CO2 into biomass and O2 is much less than 100%. The only example we have of a process that can globally alter the CO2 and O2 of an entire plant is global biology. On Earth the efficiency of the global biosphere in using sunlight to produced biomass and O2 is 0.01%. Thus the timescale for producing an O2 rich atmosphere on Mars is 10,000 times 17 years, or ~ 100,000 years. This is shown as Step #7 in Table 1. In the future, synthetic biology and other biotechnologies may be able improve on this efficiency. The 0.01% efficiency of the biosphere represents an ecological constraint, averaging over oceans, deserts and forests. The intrinsic efficiency of photosynthesis in terms of a unit leaf is much higher, about 5%. If this could be utilized over the entire area of Mars (an unlikely possibility) then the timescale for O2 production becomes a few hundred years.

Indigenous Martian life

The scenario outlined above is based on the assumption that life will not be detected on Mars. If life is detected in a living or revivable state, and if biochemical investigation determines that that life is a second genesis of life then the scenario must change dramatically. The motivation for altering Mars is no longer focused on Earth life but instead is focused on enhancing the richness and diversity of the indigenous Martian life.

Immediately when a second genesis of life is discovered on Mars all previous robotic landers and rovers would be removed from the surface or sterilized in place. It is current international policy to clean, but not sterilize, missions to Mars. The net result is that there are currently more than about 1 million dormant, but viable, Earth microorganisms in spacecraft on Mars. If Mars were warmed and water flowed, then these microorganisms would be able to revive and reproduce – potentially interfering with the native life.

Once all Earth life is removed or destroyed then “terraforming” would proceed based on the assumption that Martian life would thrive best in warm and wet conditions. This assumption would need to be checked but is very likely to be correct. The early history of Mars was warm and wet and thus any life that originated on early Mars is likely to be similar to Earth life in requiring liquid water conditions.

Any indigenous life on Mars is likely to be microbial and while it may spread globally on a Mars that has been altered to be warm and wet, there would not trees and hence not widespread forests. This means that the rate of biological production of O2 on a Mars populated by indigenous microbial life would be much less than in the case considered above with a biology based on advanced Earth life – i.e. trees. Thus the timescale for the production of an O2 rich atmosphere might be much longer than the 100,000 years estimated for Earth life and may not occur at all. However this is not a problem, because the goal of terraforming in the case of indigenous life is not focused on creating an environment suitable for humans.

Some references of interest:

Graham, J. M. (2004). The biological terraforming of Mars: planetary ecosynthesis as ecological succession on a global scale. Astrobiology, 4(2), 168-195.

Marinova, M. M., McKay, C. P., & Hashimoto, H. (2005). Radiative‐convective model of warming Mars with artificial greenhouse gases. Journal of Geophysical Research: Planets (1991–2012), 110(E3).

McKay, C.P. (1990) Does Mars have rights? An approach to the environmental ethics of planetary engineering. in Moral Expertise, ed. D. MacNiven, Routledge, New York, p 184-197.

McKay, C.P., Toon, O.B. and Kasting, J.F., 1991. Making Mars habitable. Nature, 352(6335), p.489.

McKay, C. P., Toon, O. B., & Kasting, J. F. (1991). Making Mars habitable. Nature, 352(6335), 489-496.

McKay, C. P. (2009). Planetary ecosynthesis on Mars: restoration ecology and environmental ethics. Exploring the origin, extent, and future of life: Philosophical, ethical, and theological perspectives, 245-260.

McKay, C. P. (2011). Planetary Ecosynthesis on Mars and Geo-Engineering on Earth: Can We? Should We? Will We?. In Engineering Earth (pp. 2227-2232). Springer Netherlands.

 

Is it possible to create a viable atmosphere on Mars?

James Kasting has answered Unlikely

An expert from Pennsylvania State University in Atmospheric Science

I’m a coauthor on a very old (1989) Nature paper on the possibility of terraforming Mars. I was brought on to the paper to try to inject some realism into the topic. I’m afraid that after all these years, I’m still not optimistic about the chances for terraforming the planet or, as you put it, creating a viable atmosphere. It’s difficult to release the bound-up CO2, the N2 is all gone, and the time scale for producing O2 is very long.

I would leave this topic to the science fiction writers and filmmakers. I do recommend the original ‘Total Recall’ film if you want to see a more upbeat take on terraforming Mars.

 

Is it possible to create a viable atmosphere on Mars?

Francois Forget has answered Extremely Unlikely

An expert from Centre National de Recherche Scientifique in Planetology

A “viable atmosphere” could be defined as an atmosphere that would allow humans to walk without spacesuit on Mars (i.e. with only warm clothes and an oxygen mask). This would require a surface pressure of at least 250 mbar, while the mean surface pressure on Mars is currently 6 mbar.

It is almost impossible to import the equivalent of 250 mbar of gases on Mars from another planet or from comets. It corresponds to about 10^15 tons of gases, while a a typical rocket can send only a few tons toward Mars… One could divert comets or asteroids toward Mars but It would require about 1 million of 1 km-radius comets to create a viable atmosphere.

Unlike what suggested in the 1980s-1990s, the new era of Mars exploration spacecrafts that have continuously studied Mars since 1997 have demonstrated that there is very little amount of potential gases available to create a 250 mbar. Frozen CO2 ice reservoirs have been discovered on the surface and in the subsurface by radar but heating and subliming them would add a maximum of ~10 mbar in the atmosphere. Heating the regolith could also desorb CO2 from the regolith, but only a few millibars.

The only possible solution would be to “burn” or chemically process Carbonate Rocks (which contains carbon dioxide molecules) from the surface to release CO2 into the atmosphere. One problem is that very little Carbonate reservoir has been identified at the surface of Mars, in spite of intense research by remote sensing instruments. Furthermore if extensive subsurface carbonate reservoir are found the mining work and the energy needed would be gigantic.

 

Is it possible to create a viable atmosphere on Mars?

Viorel Badescu has answered Likely

An expert from Polytechnic University of Bucharest in Thermodynamics

Yes, it is possible. The terraforming process may take thousands of years, however, and not the entire surface of Mars may become similar in climatic features as the Earth.

 

Is it possible to create a viable atmosphere on Mars?

Richard Ulrich has answered Likely

An expert from University of Arkansas in Chemical Engineering

The short answer is “yes”, you can in principle terraform the atmosphere of Mars into something that could support Earth-like life.

The first thing to realize is that Mars, despite being about half the diameter and a small fraction of the Earth’s mass, can hold a thick atmosphere indefinitely. To prove this to yourself, look at the Saturn moon called Titan. It is considerably smaller than Earth and even Mars but it’s held an atmosphere that’s 50% thicker than hours for around four billion years. So once established, Mars could hold an Earth-like atmosphere virtually forever.

So how do you make one and what would you want in it? The best route would probably be to find a bunch of carbonate rocks that are on Mars and use solar energy to chemically reduce them to carbon dioxide gas. We expect those sort of rocks to be plentiful on Mars, although possibly buried beneath ancient lava. Once you build up an atmosphere of pure CO2 at about 1 atmosphere this will provide two useful things:

  1. A gas that plants like.
  2. Lots of global warming so it’ll be warm enough to live on Mars.

Once you then get some crops going they will make oxygen, just as ours did a couple of billion years ago, and you’ll eventually get something people can breath and live in and grow food in.

 

Subscribe to
Our Newsletter