Moving To Mars: Mankind’s Next HomeBy: Blake Ives

The ultimate future of the human race is unknown, but some day there will be a need to

leave our beloved home planet, Earth. Any number of events could be cause for interstellar

colonization; a global-extinction-sized asteroid on a collision path with Earth, our sun’s eminent

expansion into a red giant as it nears the end of its life, global nuclear fallout, or even the

invasion of hostile alien species. Regardless of the reason we need to leave the planet,

interplanetary colonization will be essential for human survival. The first stepping stone to the

preservation of the human race is life on Mars. Living on Mars has been the premise behind

generations of science-fiction works including Outpost Mars by Cyril Judd, Arthur C. Clarke’s

The Sands of Mars, and Kim Stanley Robinson’s Mars trilogy: Red Mars, Green Mars, and Blue

Mars. As technology continues to advance, the concept of colonization is becoming less of

science-fiction and more of a reality: however, there are still many obstacles that must be

overcome if humans are to live on the “Red Planet” someday.

This article will present and discuss key factors, obstacles, developments and headways,

and strategies for colonizing Mars.

Why Mars?

When considering galactic colonization, a common question among theorists and

scientists is not, “Should we colonize?” but rather, “Where should we colonize first?” There are

plenty of reasonable options when it comes to our “cosmic backyard,” the solar system: Venus,

the planetary body most similar to Earth in composition, size, density, and one of our

neighboring planets; Europa, one of Jupiter’s moons which contains liquid water and a thermally

active core that could easily harbor biological development; the Moon, the closest planetary body

to Earth, and one that we have set foot on before; and Mars, another neighboring planet and one

that may lie within the “Goldilocks Zone” where astronomical conditions are appropriate to

harbor life. While there are pros and cons to colonizing each body, public interest in Mars is

high. Since public interest often affects funding, Mars is a front-runner for a future human

habitat.

Mars attracts attention

because it is the most publicized of

our fellow solar-satellites. Often

advertised as being similar to our

beloved Earth itself, Mars is a

reasonable consideration for

scientific inquiry. Mars and Earth

do in fact have a lot in common.As

seen in Figure 1, the Martian day

(24 hours 39 minutes 35 seconds)

lasts nearly the same as Earth’s

[1]; Mars has an axial tilt, causing

seasons [1]; the polar ice caps and

soil contain deposits of water [2]

[3]; gravity on Mars’ surface is 3.711 ms2 , roughly 38 %of Earth’s [4]. But, while those

Figure 1: Comparison of basic Earth and Mars properties Credit: NASA

similarities are enticing criteria for a retirement home, there is much dissimilarity that would

make living on Mars quite difficult.

Obstacles We Would Face:

While Mars is one of the closest planets to our home world, and shares many favorable

characteristics, there are quite a few critical factors that need consideration before launching to

another planet. These factors range from alien environment to physical and psychological wear

to cost and permanent living arrangements. All of these issues are essential to colonists’ survival

and must be carefully evaluated when considering colonization missions.

Martian Environment:

Life on Mars would be vastly different from the day-to-day ease it is here on Earth. The

largest measureable difference is the environment. The Martian atmosphere is predominantly

carbon-dioxide gas, CO2, which is poisonous to all life on Earth in large quantities. On Mars,

carbon-dioxide composes roughly 93% of the atmosphere, whereas on Earth carbon-dioxide

makes up roughly 0.04 % [4][5].

The high percentage of carbon-dioxide in Mars’ atmosphere poses a poisonous threat to

any normal earthling. This problem has been approached in a number of ways. One method is

to transport dark lichen, algae, and bacteria to the Martian surface. These organisms would

convert CO2 into small amounts of oxygen, produce carbohydrates, and raise the planet’s average

temperature, −63℃ (−76℉ ) , by reducing the planet’s albedo radiation1 and trapping more

thermal energy [4][5][6]. An alternative method is to import mass quantities of hydrogen gas

into the atmosphere. Using known gas properties, the hydrogen could react with carbon dioxide

to produce methane and water via the Sabatier reaction2 [7]. The water and methane produced

could be easily used by colonists to maintain their habitat and daily lives.

1 Albedo radiation refers to the amount of incident radiation from space that is reflected off a planet’s surface back into the atmosphere or space. 2 The Sabatier reaction, given by the equation (C O2+4 H 2→ C H4+H 2O ) is a process underwhich carbon dioxide and hydrogen gas combine with energy under pressure to produce methane gas and water.

Other environmental differences include the thin atmosphere and lack of a strong

magnetosphere3. The Martian atmosphere is 6.36 millibars of pressure on average, one hundred

sixty times thinner than the average atmosphere on Earth’s surface, 1014 millibars [4][8]. To

survive such low atmospheric pressure

on Mars colonists would require

pressurized suits. A strong

magnetosphere, will partially shield a

planet from solar, albedo, and cosmic

radiation. As seen in Figure 2, Mars

has a much weaker magnetosphere

compared to Earth. Since Mars does

not have a strong magnetosphere, the

surface of the planet experiences high

levels of radiation [9]. Exposure to

high levels of radiation can cause

radiation sickness or even death amongst humans.

The Radiation Assessment Detector (RAD) on the Curiosity rover measures radiation levels

on the Martian surface. According to Hassler [10], RAD is designed to determine both

atmospheric composition and radiation levels on the Martian surface. Although RAD data is not

yet available for comparison, it is certain that current space suits, which are designed for high

radiation - low pressure environments, would need to be modified to account for the change in

radioactive exposure.

Human Health:

Another consideration for colonization would be psychological and physical health. The

most efficient and safest journey to Mars takes roughly seven months [11]. Being confined in a

small spacecraft with 3-5 people for seven months, then spending years disassociated with life on

Earth, combined with the stresses of adjusting to life in an entirely new terrain could be mentally

exhausting. The European Space Agency (ESA) and the Russian Academy of Sciences Institute

3 A magnetosphere is comprised of an electromagnetic field often produced by a rotating planetary core.

Figure 2: Solar wind hitting Venus (top) Earth (middle) Mars (bottom). Earth has a strong magnetosphere and therefore is

more protected from radiation from space. Credit: ESA

for Biomedical Problems (IBMP) conducted the Mars500 experiment, a simulation of the seven

month journey to and from Mars, to analyze psychological effects of long term isolation. Six

“marsonauts” were locked in a capsule near Moscow, Russia for 520 days to simulate the trip to

and from our red neighbor. According to the ESA,

“In addition to being helpful in determining psychological aspects of spaceflight, this

research has been invaluable in determining radiation hazards and the adaptation to

weightlessness, as well as in the development of life support systems” [12].

Living on Mars would certainly have physical detriments as well. Tests aboard space

stations, as well as astronaut health exams post spaceflight, have determined that human bodies

deteriorate rapidly in microgravity. According to Joyner, long-term exposure to microgravity

causes decreases in bone density, cardiovascular efficiency, and muscle mass [13]. However,

since these tests were conducted in microgravity while orbiting Earth, it is not certain how the

human body will react to Martian gravity.

Price:

Space travel is not by any means cheap. One of the most recent missions to the “Red

Planet”, the Mars Science Laboratory (dubbed “Curiosity”), cost NASA roughly $2.5 billion

[14]. Prospective costs of colonizing Mars start in the hundred billions of dollars for research,

design, construction, and habitat stabilization. However, the cost diminishes significantly if

astronauts sent to Mars would not be returning home. Providing a “one-way-ticket” to Mars

would cut all costs of materials, fuel, and construction of a Martian launch vehicle, as well as

transporting those materials to the planet itself.

The introduction of the private space sector will also reduce the price of future missions

to Mars. According to SpaceX founder Elon Musk, “an advanced, reusable system could allow

individuals seeking round trips to Mars for just $500,000” [15]. Groundbreaking organizations

like SpaceX, MarsDrive, and MarsOne are advancing space technologies to make spaceflight

both more affordable and more accessible.

Energy:

One problem with space travel is the production of electricity and power. Spacecraft

power supplies can range from nuclear reactors to pre-charged batteries; however, the most

commonly used energy source for medium to long duration space missions is solar power. Solar

power, or the production of electricity through photovoltaic cells, has often been considered

expensive and inefficient. Fortunately, continuous research has made the technology cheaper, as

well as more energy effective. Between early 2008 and April, 2012, the cost of photovoltaic

cells decreased nearly 75%, from $3.88/W to $1.01/W [16]. To determine the most efficient

method for converting light into usable energy, solar power companies are also experimenting

with cell composition and layouts. Companies like TetraSun and AltaDevices have created cells

that absorb visible light with 20%-30% efficiency [17]. While these companies focus on visible

light, research is being conducted at centers across the United States to include other ranges of

the electromagnetic spectrum. It has been estimated that solar cells could improve up to 80%

efficiency by including other areas of the spectrum [18]. With the continual decrease in

production cost and increase in efficiency, solar energy will likely be a main source of power for

future Martian inhabitants.

Another mechanism that will be essential to Martian life is the fuel cell. Fuel cells are

devices which create electrical energy through means of chemical reaction. Due to increased

carbon emissions on Earth, ongoing studies at Princeton University are attempting to combine

carbon dioxide (C O2) with hydrogen and oxygen to produce hydrocarbons for fuel [19]. The

main problems the research team faces are funding and gathering large quantities of resources.

With the lab’s current product efficiency, to match the oil industry’s power output the team

would require 8,500 moles of C O2 per barrel of oil consumed in the United States [19]. While

such quantities of carbon dioxide are difficult to obtain on Earth, the Martian atmosphere is 93 %

carbon dioxide, making the fuel cell a viable power source. If the team can make the process

affordable, C O2 powered fuel cells could decrease the concentration of the poisonous gas in the

Martian atmosphere while also providing a steady power supply for future colonists.

How will we survive?

Companies, corporations, and individuals have been suggesting detailed plans for safely

and cheaply forming a colony on Mars for many years. The first theory I ever heard was that of

my seventh-grade space camp counselor, “First, melt the polar ice caps and glaciers with lasers

from satellites. Then, pot plants all around the planet so they can turn the carbon dioxide into

oxygen for us. Lastly, put up an umbrella to block the radiation.”

To his credit, many theories for terraforming Mars recommend melting the polar ice caps

to produce useable water; however, melting the caps would release trapped C O2 molecules and

increase the toxicity of the Martian atmosphere

even further [20]. A more practical concept would

be to avoid the harsh environment by living

underground in caves or empty lava tubes. These

underground caverns would shield inhabitants

from the dangerous levels of radiation and cold

temperatures [21]. Another, highly publicized,

concept is to live in a giant structure on the surface

that supports an artificial environment, known as a

biodome. A biodome on Mars would be similar to

John Allen’s Biosphere 2 experiment performed at

the University of Arizona [22]. The biosphere

used in the experiment was an structure fit for self-

sustainability and contained all necessary elements

for human survival. However, biodomes on the

Martian surface would still be subject to higher

levels of radiation than living deep within the

planet. Despite the higher radiation threat,

versions of surface habitats similar to the biodome

have been adopted by most organizations like SpaceX, MarsDirect, MarsOne, and NASA’s Mars

Design Reference Mission, who are seriously interested in long term manned missions to Mars,

due to the practicality and ease of construction on the surface compared to that of underground

habitats.

Figure 3: Artist renderings of possible Martian colonist habitats.

(Above) Use of lava tubes and caves [NASA] (Below) Surface biodomes [MarsFoundation]

Summary:

While many great challenges, ranging from environment to psychological stability to

habitat construction, must be overcome before humans can colonize Mars, many technological

feats have made moving to the “Red Planet” closer to a reality. Research and advancements in

space technology, human safety, and alien environments are only the beginning of a long journey

to land humans on another planet in our solar system. With innovative organizations like NASA,

SpaceX, MarsDirect, and MarsOne leading the way in space exploration, living on Mars may no

longer only be the dreams of science-fiction novelists anymore.

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