Glenn Stok has a Master of Science degree and applies his research to educate his readers with information on science and philosophy.
With all the talk of a mission to Mars and the idea to actually colonize the planet, it still remains a distant reality. The stress of the trip, both mentally and physically, and human survival while ultimately living there, involves enormous problems that scientists need to consider. This article is a discussion of the issues involved with this mission.
The Challenges of Space Travel to Mars
Before we consider the challenges of living on Mars, the transportation to get there needs to be better understood. Daniel Strain, a science writer at the University of Colorado, suggests the following critical considerations.1
- Astronauts on the International Space Station never stayed that long, and we have no idea what issues the human body might encounter with three years of weightlessness.
- Depending on the orientation of Earth and Mars at the time of departure, it could take astronauts three years or longer to get there.
- During the trip, if something goes wrong, and they need to contact personnel on Earth, it can take up to 20 minutes for radio signals to be received, and double that for a verbal response sent back.
- Remote health checkups with doctors will also be challenging. For example, electrocardiogram (ECG) data has that same delay for relaying to Earth.
Considerations for Human Survival
With an environment on Mars that’s hostile to human life, we need to consider the following:
- We need to protect ourselves from cosmic rays. Earth has a magnetic field diverting them to our poles.
- Mars has a different atmosphere that is not favorable to humans.
- Mars has a weaker gravity that will affect how we move around.
Robotic missions with rovers found raw materials that we could use to construct communities so that we would not need to send these raw materials from Earth.
Mars is the most Earthlike planet in our Solar System, so it’s the best candidate for colonization. Over three billion years ago, it was more like Earth is today, with life-supporting flowing water and a cosmic ray protective magnetic field.
The planet lost both of these since then, but scientists have hope of terraforming Mars to bring it back to a human habitable condition, as I will discuss.
With the upcoming planned missions beginning in 2022, we may be able to start the long process of bringing some of the Earthlike environmental attributes back to the planet. The other issues, such as the danger of cosmic radiation, can be dealt with by other means.
Lack of Potable Water on Mars
NASA has already discovered water on the planet that could help sustain human life, but most of it is in the form of ice. It’s on the surface only at the northern pole of Mars.
In September 2020, Mars Express, the European Space Agency’s Mars-orbiting spacecraft, found a large lake under the ice at Mars’s south pole containing saltwater.2 However, that would need to be processed to make it useful for human consumption.3
Lack of a Protective Magnetic Field as We Have on Earth
We know that we are protected here on Earth by its magnetosphere that diverts the dangerous solar particles and cosmic rays to the poles—away from inhabited areas. That's what causes the Aurora Borealis (northern lights) and Aurora Australis (southern lights).
The magnetosphere is a magnetic field that exists because our planet has a metallic core. But what about Mars?
Mars had a magnetic field once. It was lost over 3.7 billion years ago, possibly due to multiple asteroid strikes that destroyed the dynamo effect of the planet’s internal magnetic core.4
That means we would need some other method to protect us from cosmic rays that are bombarding the planet.
The fact is that we would never be able to enjoy a day outside without protective suits. Even if there were an atmosphere, we still couldn’t go out without protection as we do on Earth.
All our daily activities would need to be inside buildings that protect us from cosmic rays while living on Mars. Possibly even building underground living quarters would be mandatory.
People Can’t Breathe the Air on Mars
The major part of the Earth's atmosphere that we breathe is 78% Nitrogen and 21% Oxygen, while the atmosphere on Mars is 95% Carbon Dioxide. That’s great for plants, which absorb Carbon Dioxide for photosynthesis in sunlight to produce oxygen. However, Humans need oxygen to breathe and provide energy to our cells.
Mars does have an atmosphere, but it is very different from our atmosphere on Earth, as shown in the table below.
Carbon Dioxide is the most abundant, and can be converted into oxygen, as plants do with photosynthesis here on Earth. But if we were to consider planting trees on Mars to convert the atmosphere, that takes time to make it breathable.
Even if we can breathe the air, the chemical makeup that I described above is not conducive to human survival. Besides, the pressure of its atmosphere is so low that water boils at the temperature of the human body. Humans will lose consciousness when exposed at that level—known as the Armstrong Limit.
The atmospheric pressure on Earth at sea level is 14.69 psi. The average pressure on Mars is 0.087 psi.5
Humans definitely could not survive at this low pressure. To enter and leave living quarters, one would need to go through an airlock so that the proper atmosphere inside can be maintained. They would always have to spend their time in a pressurized environment.
Nitrogen (N): 78%
Carbon Dioxide (CO^2): 95.32%
Oxygen (O): 21%
Argon (Ar): 1.9%
Argon = (Ar): 0.93%
Nitrogen (N): 2.7%
Carbon Dioxide (CO^2): 0.04%
Oxygen (O): 0.13%
Neon (Ne): 0.001818%
Carbon Monoxide (CO): 0.08%
Helium (He): 0.000524%
Sulfur Dioxide (S): Trace amount
Methane (CH4): 0.000179%
Methane (CH4): Trace amount
Other gases: Trace amounts
Other gases: Trace amounts
Comparison of Gravity on Earth and Mars
Gravity on Mars is generally only 38% that on Earth. Therefore, if you weight 170 lbs on Earth, you’d be 65 lbs on Mars.
Gravity is a result of the attraction between masses. The larger the mass of an object, the stronger will be its gravity.
Our Sun's gravity keeps all the planets circling it in our solar system without flying away into the outer limits of the galaxy. The gravitational pull of the planets also holds their moons in orbit.
Since Mars is smaller than Earth, as shown in the image below, its gravity is weaker. You might have seen videos of Neil Armstrong and Buzz Aldrin walk on the Moon on July 20, 1969. Their footing was strange as every step they took sent them hovering for a moment due to the weaker gravity.
That would not be the same when walking on Mars since it's much bigger than our moon. Nevertheless, it still would be very different from the firm footing we’ve developed since learning to walk as toddlers.
Gravitational pull is weaker the higher you go, away from the center of mass. That becomes more mathematically complex on Mars because its southern hemisphere has less mass than its northern hemisphere.6
It’s essential to consider these gravity anomalies when planning to bring equipment and supplies to Mars for future colonization.
It’s Cold on Mars but Still Within the Sweet Spot
Since Mars is approximately 142 million miles from the Sun, it’s colder than Earth, which is only 94.47 million miles from the Sun.
The average temperature of Mars is -85° Fahrenheit (-65° Celsius). That is extremely cold for humans. However, when you consider that Venus gets as hot as 867° Fahrenheit (464° Celsius) and Neptune gets as cold as -328° Fahrenheit (-200° Celsius), Mars is within the sweet spot.7 It’s within a range that we can deal with using present-day equipment within the living quarters.
In the summer, the temperature on Mars can warm up to -24° Fahrenheit (-31° Celsius). Still quite cold, but livable.
We still have a lot to learn about the evolutionary history of Mars, and we’ll learn much more when we colonize the planet. We already know that it went through global cooling at least once—bringing it to the state it’s in now.
Can We Make Mars Inhabitable?
Scientists are already examining ways to transform Mars by creating greenhouse gases that could increase the pressure of the atmosphere well above the Armstrong Limit (Which I spoke about earlier).
This process is known as terraforming. It’s still hypothetical, but it would allow for sustainable colonization of Mars by transforming it over time to become more like that of Earth, so it's favorable to humans.
Is Terraforming Mars Feasible?
In a 1961 article in the Science Journal, astronomer Carl Sagan proposed an idea to influence the global environment of Venus.8 Scientists are now considering that for Mars, with the process of terraforming the planet by planting trees and other vegetation.
Terraforming would require enough CO2 and water vapor for trees to flourish and bring the oxygen level up to 21% as we have on Earth. Mars’ atmosphere does have 95% CO2 already, so the idea seems feasible.9
Some types of trees may withstand the colder temperatures on Mars. For example, Apple trees are known to grow in cold climates and survive under a blanket of snow. Scientists are already experimenting with growing plants in Mars soil on the International Space Station.10
In addition to planting trees to produce oxygen, which will take hundreds of years before humans can breathe the air, other technologies are available to produce oxygen.
MOXIE Experiment to Make Oxygen on Mars
An experimental process called solid oxide electrolysis will produce pure oxygen from the carbon dioxide that’s present in the Martian atmosphere. Since there is an abundant 95% supply of CO2 available, this can have significant results.
The experiment is named MOXIE (Mars OXygen In situ resource utilization Experiment).11
It will be implemented as a scale model 1% normal size on a robotic Mars rover planned for launch in 2020 in preparation for the upcoming Mars missions.
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How Is NASA Preparing for a Journey to Mars?
Since 2015, NASA has been putting a lot of attention to all the prerequisites necessary for a successful mission.12 They have used robotic pathfinders, such as rovers Spirit and Opportunity, to map the surface of Mars and find destinations for upcoming human missions. These rovers do the following jobs:
- Collect surface samples,
- Conduct seismic investigations,
- Locate potential landing sites,
- Test developed technology systems,
- Select human-accessible landing sites,
- And position required infrastructure.
A Breakthrough With the Ingenuity Helicopter
In March 2021, NASA achieved a significant accomplishment by flying a helicopter on Mars despite the thin air.
That gives us a more efficient way to do analysis of the terrain. See how it works in this narrated documentary video:
Elon Musk: "We're Going to Mars by 2024"
Mars-bound cargo flights are being planned for 2024 with funding by SpaceX (Founded in California by Elon Musk), using their Falcon 9 and Falcon Heavy launcher. Elon Musk discusses his plan in this eight-minute video:
Considering Human Colonization of Mars
Living on Mars will never be similar to that on Earth. A method to protect the human body from cosmic radiation will continue to be a concern, requiring special living quarters and protective suits when venturing outdoors. Possibly underground communities might be the solution.
It Would Be a Permanent Settlement
The astronauts would not be returning to Earth. Some people in academia call this a suicide mission. However, if they succeed at living out their lives on Mars, I would consider it a relocation plan. The purpose, after all, is a permanent Mars settlement of a human colony.
Those who go will have accepted the fact that they will have no family or friends other than the crew involved in the mission. Survival in case of illness will be dependent on the team that will include a doctor and surgeon.
Robotic surgery can be performed remotely by surgeons on Earth. We have that type of equipment and technology now, such as the “da Vinci Surgical System" used for prostate surgery. The only issue is the 20-minute delay with data transmission. However, that might be solvable with autonomous surgery. That could handle tasks during delays with remote control.13
Contradictions With Research
Some scientific studies contradict other discoveries. In July 2018, results of prior missions indicate that there was not enough CO2 remaining on Mars for creating greenhouse warming.14 But that might be disproven with later studies being conducted.
NASA is also saying that terraforming is not possible with our present technology. But they are going ahead with plans based on newer studies.15
Now with the Helicopter Ingenuity, the Perseverance Rover, and the Odyssey Orbiter mapping Mars since December 2001, many pieces of the puzzle are falling into place.
NASA continues investigating Mars with further analysis of the atmosphere and rock samples. As the work continues, we can only imagine what comes next.16
- Daniel Strain. (March 2, 2021). “Help is a long way away: The challenges of sending humans to Mars.” colorado.edu
- Jonathan O'Callaghan. (Sept 28, 2020). “Water on Mars: discovery of three buried lakes intrigues scientists.” Nature.com
- “Potable Water.” (Retreived April 2021). Water Education Foundation
- Lisa Grossman. (Jan 20, 2011). "Multiple Asteroid Strikes May Have Killed Mars's Magnetic Field." Wired.com
- R. M. Haberle. (January 1, 2015), "Solar System/Sun, Atmospheres, Evolution of Atmospheres | Planetary Atmospheres: Mars", Gerald R., John Pyle, Fuqing Zhang (eds.), Encyclopedia of Atmospheric Sciences (Second Edition), Academic Press, pp. 168–177, ISBN 9780123822253
- C. Hirt, S.J. Claessens, M. Kuhn, W.E. Featherstone. (July 2012). "Kilometer-resolution gravity field of Mars: MGM2011". Planetary and Space Science. pp. 147–154.
- Planetary Fact Sheet. NASA.gov
- Carl Sagan. (March 1961). "The Planet Venus." Science, Volume 133, Issue 3456, pp. 849-858
- Martyn J. Fogg. (August 1992). “A synergic approach to terraforming Mars.” British Interplanetary Society, Journal (ISSN 0007-094X), vol. 45, no. 8, Aug. 1992, p. 315-329.
- Gary Jordan. (August 7, 2017). "Can Plants Grow with Mars Soil?" NASA.gov
- M. Hecht, J. Hoffman, D. Rapp, J. McClean, J. SooHoo, R. Schaefer, A. Aboobaker, J. Mellstrom, J. Hartvigsen, F. Meyen, E. Hinterman. (January 6, 2021). "Mars Oxygen ISRU Experiment (MOXIE)". Space Science Reviews. 217 (1): 9. doi:10.1007/s11214-020-00782-8. ISSN 1572-9672.
- "Journey to Mars." (October 8, 2015). NASA.gov
- Meera Senthilingam. (May 12, 2016). “Would you let a robot perform your surgery by itself?” CNN.com
- Bruce M. Jakosky and Christopher S. Edwards. (July 30, 2018). “Inventory of CO2 available for terraforming Mars.” Nature Astronomy
- Bill Steigerwald and Nancy Jones. (July 30, 2018). “Mars Terraforming Not Possible Using Present-Day Technology.” NASA.gov
- “Mars Exploration Program.” Mars.NASA.gov
© 2019 Glenn Stok
Glenn Stok (author) from Long Island, NY on May 23, 2020:
NASA had concluded that terraforming Mars is not possible with our present technology, so I updated this article with a different conclusion.
Ken Burgess from Florida on June 23, 2019:
The benefits would far outweigh the costs.
The knowledge gained, the technology invented, will only be achieved by the journey.
Perhaps the efforts to convert the CO2 rich atmosphere will lead to discoveries and knowledge that helps Earth's issues with CO2.
The argument to focus all our efforts on activities here on Earth are shortsighted. That is akin to saying "I'm not leaving my house until I am physically perfect, know everything there is to know, etc." That day is never going to come.
Our ability to expand humanities horizons, change what we believe to be possible, and get beyond our petty tribal differences will not come until we move ourselves beyond this planet, and that first step is Mars... which may eventually lead to going much further, beyond the solar system even, but that is not even a possibility if we do not take that first step off of Earth.
Glenn Stok (author) from Long Island, NY on June 23, 2019:
Heidi Thorne - You hit upon a very important point. The forces of nature and the enormous physical phenomenon of the universe will always stand in the way of anything we hope to accomplish in the long-term. Eventually our own Sun will die, and whatever we do to extend the existence of the human race on another planet will effectively be in vain.
Heidi Thorne from Chicago Area on June 23, 2019:
Well, this is a very thoughtful and detailed discussion of the topic!
I do think humanity will, one day, make it to Mars to visit and maybe colonize/terraform. But there are so many issues, technical and human, that need to be worked out.
I do agree that we need to clean up our act on Earth before we go someplace else. I also agree that while humans have had negative impact on our planet and atmosphere, we are just in the midst of yet another ice/greenhouse cycle. To think that we can totally impact or even control all of Earth's and our solar system's forces is sheer hubris. That should also give us pause to consider how much we could or should tame another planet to accommodate our habitation.
Thanks for this interesting read!
Glenn Stok (author) from Long Island, NY on June 22, 2019:
Thank you everyone for your mindful comments. It’s clear that you all have a keen grasp of the undertaking.
Glenn Stok (author) from Long Island, NY on June 22, 2019:
Ken Burgess - You explained it very well Ken. Yes, our concept of humanity will change once we have a few people living on Mars. The experience through their eyes will give us a whole new feeling about where we are, how we treat others, and where we're going. Thanks so much for you expressive comment.
Stella Kaye from UK on June 22, 2019:
Excellent article. My own opinion is that humans need to sort their own planet out first before considering the establishment of extra-terrestrial colonies. Earth offers the best environment to be found anywhere, yet humans have completely messed it up in less than a couple of centuries. They have polluted the air, the land and the sea and depleted natural resources and habitat. Even if it is possible to live on Mars, proper management of Earth should come first.
Pamela Oglesby from Sunny Florida on June 22, 2019:
I can't quite imagine people living on Mars, even though they have solved some of the numerous problems. I agree with your opinion. I imagine somewhere in another galaxy there is a planet similar to ours, but we can't travel that far at this time. Anyway, it would not be for me.
Ken Burgess from Florida on June 21, 2019:
I think this is the greatest challenge, and the highest goal humanity can currently set for itself.
Colonizing Mars successfully means we can move beyond Earth, it means we are not limited to Earth, and this would change everything... our perceptions of who we are, what our future is, what is possible, what can be achieved all changes when we successfully colonize Mars.
It also makes us a bit more in control of our destiny, and not subject to the whims of fate, our species might not end because a stray meteor hits earth, or a burst of radiation from the sun penetrates the ozone for a moment long enough to fry our civilization.
It doesn't have to be a massive colonization, they could successfully build a colony in a lava tube large enough to protect them from the Sun and the worst of the elements.
The plans would be to become self-sufficient there, perhaps terraforming part of the planet eventually, but initial small steps which could lead to bigger ones in a generation or two.
Elon Musk and others have stated we should consider Mars not just a stepping stone to the stars, but as a back-up for potential disaster that devastates Earth, having the ability to return from mars and re-establish civilization is a great insurance plan to have, because right now, there is none... and if something goes wrong on Earth today, civilization is done for, and we may well be knocked back to the stone age.
Liz Westwood from UK on June 21, 2019:
This is a very thorough and interesting article. You have tackled the question very well, posing and answering other questions as you work through the subject. Science fiction becomes reality.