Life Support Systems for Manned Mars
Missions, Overview
Thais Russomano
Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Effects of a Hostile Environment on an Earth-Adapted Physiology . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Potent Problem of Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Psychological Stress of Being Far from Home . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Advent of Advanced Life Support Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Closing the Loop on Regenerative Life Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Calculating the Ins and Outs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bioregeneration as a Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
In Situ Resource Use: An Important Addition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Making Fiction a Reality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cross-References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Abstract
A manned journey to Mars has long since been the subject of science fiction and
fantasy, but continued advances in technology have opened up the possibility.
The lengthy distance to the planet, together with its hostile environment present
dangers to the health and well-being of space-travelers and huge logistical
difficulties in terms of adequate resource provision to sustain a crew for a return
journey and time on the planet surface. Advanced life support systems have
continued to adapt and develop since the flight of Russian cosmonaut Yuri
Gagarin in 1961 and the NASA led Mercury, Gemini, and Apollo missions,
T. Russomano (*)
Microgravity Centre, The Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
International Space Medicine Consortium Inc., Washington DC, USA
Centre of Human and Aerospace Physiological Sciences, Faculty of Life Sciences and Medicine,
King’s College London, London, UK
e-mail: [email protected]
# Springer International Publishing AG 2017
E. Seedhouse, D. Shaler (eds.), Handbook of Life Support Systems for Spacecraft and
Extraterrestrial Habitats, DOI 10.1007/978-3-319-09575-2_188-2
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which required open-loop, disposable systems of short duration only. Arrival of
the Space Shuttle program and International Space Station led to a shift in
specifications, with emphasis on reusability and long-term use. This ongoing
process has resulted in a complex life support system capable of sustaining a
six-astronaut crew for several months. Key technologies, such as oxygen generation and water recovery systems, have reduced the need for the costly resupply
of some materials to the orbiting space station, but replenishment of consumables,
propellant, and maintenance equipment continues. Frequent resupply is an
unfeasible option for a long-duration deep-space mission, meaning a
bioregenerative life support system will be essential. Research continues in this
field, with one example being the European Space Agency managed MELiSSA
(Micro-Ecological Life Support System Alternative) project. Further advances in
a system providing the essentials for human survival in a Mars environment,
together with technology for the use of the natural in-situ resources of the planet,
will undoubtedly open up exploration of this new frontier in the coming decades.
Introduction
A manned space journey to Mars, the fourth planet in our Solar System, will not be
an easy task to accomplish, being fraught with difficulties. The huge void of space
that separates Mars from planet Earth varies greatly depending on the orbits of the
two planets, ranging from 34.8 million miles at its closest to 249 million miles at its
furthest, with the average distance being 140 million miles. Travelling from Earth to
Mars requires more than a simple “point and shoot” launch of a spacecraft, but will
involve planning a trajectory that takes account of the huge distance and the differing
orbits of the two planets. Calculations using the Hohmann transfer orbit, which sets
the optimum elliptical orbit needed to rendezvous a spacecraft with Mars using the
least amount of fuel, have indicated a travel time of between 6 to 9 months,
depending on rocket velocity and the proximity of the planets (Seedhouse 2009).
Such lengthy flight duration will require a vast amount of propellant in order to leave
Earth’s gravity, reach Mars, and still have the possibility of returning home again. In
addition to the weight of propellant, however, consideration must be given to the
consumables that will be needed to sustain a crew for the return journey, as well as
the time spent on the planet surface, and this in itself will be a significant factor. It is
estimated that the consumables required for a crew of just six astronauts for a return
space mission to Mars will range from 100 to 200 metric tons, though it is more
likely to be nearer the higher figure. This enormous amount of weight would require
a series of heavy-lift launch vehicles to guarantee the necessary life support systems
and supplies would be accessible to the crew. Therefore, it is vitally important that
the correct balance is achieved between keeping the payload weight down to a
minimum, while at the same time ensuring all essential life support provision is
available, given that resupply from Earth or an early return to Earth are not feasible
Life Support Systems for Manned Mars Missions, Overview
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options. In order to achieve this, it will be vitally important that the life support
systems adopted for such a journey to Mars and for the time spent on the planet
surface be as self-sufficient as possible; to this end, it will be essential that the design
of the life support systems be as regenerative as possible, operating to a high degree
as a closed-loop system (MacElroy et al. 1992).
Effects of a Hostile Environment on an Earth-Adapted Physiology
The distance between the two planets is not the only difficulty. Assuming the success
of the first stage of the mission and the safe arrival of the astronauts onto Martian
soil, they will be faced with an entirely new and hostile environment to which
mankind is not yet adapted. The planet Mars is smaller and less dense than the
Earth, which creates a lower gravitational force, called hypogravity. Its thin atmosphere is rich in carbon dioxide (95%) that is a toxic gas for humans, its atmospheric
pressure is very low in comparison to Earth, and the Martian surface temperature
ranges from 140 C at the coldest polar caps to 35 C during the equatorial summer
(Russomano et al. 2008).
It can therefore be seen that the mission as a whole will submit the space travelers
to extreme conditions and environments; our experiences to-date with space travel
and Low-Earth-Orbit (LEO) space stations has already demonstrated the detrimental
physiological and psychological consequences of this exposure. Human anatomy
and physiology have been shaped by Earth’s gravitational force over millions of
years. When this force is reduced or removed, such as in the microgravity of space, it
is known that all body systems are affected. Bones that are no longer required to
support the weight of the body begin to lose their mass continuously, particularly so
in the lower limbs. Skeletal muscles that are not needed to counteract the effects of
gravity suffer a large degree of atrophy. The immune system appears to become less
active in microgravity, and the cardiovascular system adapts to the space environment by redistributing blood and fluids from the lower to the upper body, while
decreasing the plasma volume and heart size. It has been seen during space missions
that astronauts also present a reduction in the number of red blood cells, called space
anemia. The vestibular or balance system that is designed to keep our visual world
stable and keep us from falling suffers from the moment of insertion into microgravity, causing a condition called space motion sickness, which is known to affect
70% of astronauts in the first 72 h of a space mission (Barratt and Pool 2008;
Russomano et al. 2008; Seedhouse 2009).
The Potent Problem of Radiation
A major consideration having serious consequences on astronaut health is the effects
of space radiation and the degree to which they will be exposed during a round-trip
to Mars and time spent on the planet surface. Radiation can be defined as a form of
energy that is emitted or transmitted in the form of rays, electromagnetic waves,
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and/or particles. It can be divided into: visible light (radiation that can be seen),
infrared radiation (radiation that can be felt), and radiation such as x-rays and gamma
rays, which are not visible and can only be observed directly or indirectly with
special equipment. LEO space missions, such as on the International Space Station
(ISS), have shown that crew members are most likely to be exposed to high doses of
radiation during solar particle events, also called solar flares. On these occasions,
extremely high energy radiation is emitted in a short period of time. Most of this
radiation is prevented from reaching the surface of Earth and having consequent
effects on living organisms or even the astronauts on LEO missions by our planet’s
magnetosphere. NASA data has shown that radiation exposure for astronauts aboard
the ISS is typically equivalent to an annualized rate of 20 to 40 rems (200–400 mSv).
The average dose-equivalent rate observed on a previous Space Shuttle mission was
3.9 μSv/h, with the highest rate at 96 μSv/h, which occurred while the Shuttle was in
the South Atlantic Anomaly region of Earth’s magnetic field (1 Sv = 1000 mSv =
1000,000 μSv). When removed from the protection of this magnetosphere, as during
an interplanetary trip, both spacecraft and astronauts will no longer be shielded from
this radiation and will be exposed to Galactic Cosmic Rays (GCR). This radiation is
composed of high charge and energy particles – high atomic mass nuclei, which have
the ability to penetrate several centimeters of body tissue. NASA considers that a
round trip to Mars of about 1 year would expose the space crew to a total of 600 mSv.
Consideration will need to be given to means of creating greater shielding for
spacecraft headed to Mars or alternatively shortening the travel time in order to
minimize harmful exposure. Current propulsion systems are unlikely to reduce the
journey length and, therefore, improved or alternative means of shielding the space
crew are more likely to be considered. Ideas currently being suggested and investigated include: shields which rely on magnetic (or electric) fields to deflect energetic
particles; balancing the need for a shield strong enough to deflect GCR particles
while remaining weak enough so as to not harm the astronauts; artificially induced
hibernation, a state known as torpor, of crew members for the journey whereby their
metabolisms would remain at an extremely slow rate; and lining the spacecraft shell
with food and water supplies and stored human excrement, as proposed by the
Inspiration Mars Foundation plan to send a two-person crew in an orbit to Mars
and back over a 501 day nonstop journey. Although seemingly coming from the
realms of science fiction, radiation shielding is a serious concern for the health of a
space crew to Mars, both for the time en route and once landed on Martian soil
(Seedhouse 2009; Rask et al. 2012).
In order to minimize radiation exposure on the planet surface, the time the
astronauts spend outside their spacesuit and the distance they travel between their
habitats will need to be limited in order to decrease the chances of damage to their
health. If the astronauts stay on the surface of the planet while they wait for
realignment to make the journey back to Earth, it is estimated they will be exposed
to an additional 400 mSv, since the thin atmosphere of Mars is not strong enough to
shield them from most cosmic radiation. Therefore, the total radiation exposure that
the space crew will be subject to, including the journey and time spent on the planet,
is estimated to be 1000 mSv (Barratt and Pool 2008; Rask et al. 2012).
Life Support Systems for Manned Mars Missions, Overview
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The Psychological Stress of Being Far from Home
The psychological effects of being completely detached from Earth in a long-term
deep space mission are more difficult to fully predict as such an unparalleled
situation cannot be truly simulated on the ground. The Mars-500 psychosocial
isolation experiment involving an international crew of six volunteers, which concluded in November 2011, attempted to mimic the conditions of a return trip to Mars.
The group were isolated for 520 days within a spacecraft mock-up located at the
Russian Academy of Sciences’ Institute of Biomedical Problems in Moscow, Russia.
However, although isolated and “locked away” from the world, it was impossible to
truly recreate the psychological pressures that would be caused by being millions of
miles away from Earth and feeling at constant risk – after all, only a door stood
between the Mars-500 crew and safety. Nonetheless, it is known from anecdotal
reports and research that astronauts during space missions experience moments of
monotony and are affected by stressors, such as those caused by being confined and
isolated, while also contending with problems related to the lack of privacy resulting
from the restricted space provided by a spacecraft environment (Russomano et al.
2008; Vakoch 2011).
These factors must all be taken into account when contemplating the design and
content of an appropriate life support system for a manned Mars mission. The planet
on which we live has a natural life support system that has sustained us for thousands
of years, providing everything needed for the continuance of life. It delivers more
than simple biological requirements, such as the water we drink and fertile land on
which to grow food; it has an ozone layer that offers protection from the Sun’s UV
radiation; it has gas, coal, and oil that provides us with power; and natural resources
from which we create homes and commodities, among other things. None of these
natural conditions will be found in the hostile environs of outer space or Mars. These
must be artificially recreated in a system that will supply air, water, and food to the
astronauts, and deal with all body and environmental waste products, while
maintaining a living and working setting with the correct temperature and pressure
that will also provide shielding from radiation. Such an all-encompassing life
support system for a manned trip to the red planet will need to consider the two
main phases of the operation: the interplanetary mission (the outward and return
journey from Mars) and the time spent on the planet surface (Seedhouse 2009;
Shkedi 2009; Rask et al. 2012).
The Advent of Advanced Life Support Systems
The advent of advanced life support (ALS) systems were required following mankind’s first venture into space with the flight of Russian cosmonaut Yuri Gagarin in
April 1961, closely followed by US astronauts Alan Shephard and John Glenn in
May 1961 and February 1962, respectively, as part of the Mercury program. The
proceeding 50 plus years have seen advances in the environment and life support
systems found in spacecraft. The life support systems for the first three American
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space programs, Mercury, Gemini, and Apollo, were all primarily open-loop systems; they were for short-duration use and designed to be discarded, which allowed
for a much simpler system than found nowadays. The 100% oxygen atmosphere for
the crew was provided by either high pressure or cryogenic storage tanks, while the
expelled CO2 was removed by lithium hydroxide in replaceable canisters (NASA
2015). The earlier Mercury and Gemini missions stored water in tanks, while the fuel
cells of the Apollo spacecraft provided water as a by-product of electricity production. No reuse of waste products, such as urine and waste water, took place, with
these being collected and vented overboard or stored for return to Earth. The arrival
of the Space Shuttle program began a shift in the required specifications for life
support systems. These spacecraft were designed to be reusable and, therefore, the
life support system also needed to be improved and reused, although still dependent
on disposable consumables. Currently, the best example of a very complex system
that has the capability of sustaining a 6-astronaut crew, living and working in space
for several months at a time, is the life support system to be found on the orbiting ISS
– the Environmental Control and Life Support System (ECLSS) (NASA 2015). The
ECLSS was designed to perform several crucial functions for the survival of the
space crew and has included further advances in life support technologies. It
monitors, controls, and maintains an adequate environment for the crew, monitoring
and controlling partial pressure of gases (nitrogen, oxygen, carbon dioxide, methane,
hydrogen, and water vapor), cabin temperature, humidity, and pressure. It also
provides breathable oxygen for human metabolism, achieved through a process of
electrolysis of water, removes the carbon dioxide produced and expelled by crew
members, and filters microorganisms from the cabin air. In addition the ECLSS
provides a source of potable water used for crew consumption, food preparation, and
hygiene. This life support system has developed over a period of years with the
addition of certain key technologies, including the addition of an oxygen generation
(2006) and water recovery (2008) system, and the Sabatier reactor (2010), all of
which have transformed the life support to a partially closed-loop physicochemical
system. This is estimated to have reduced the annual resupply requirements to the
ISS by 10,000 kg. Nonetheless, the need for replenishment of consumables, propellant, and maintenance equipment continues, an unfeasible operation for a longduration deep-space mission, and therefore, the loop must be further closed before
a journey to Mars is possible (Shkedi 2009; NASA 2015).
Closing the Loop on Regenerative Life Support
Any mission to Mars will require regenerative life support technologies and the use
of in-situ resources to maximize self-sufficiency and reduce the need for provision
and resupply of consumables. The six main elements needed for such an undertaking, according to the NASA Advanced Life Support Document, are: air provision,
storage, and control; biomass production leading to food transformation, processing,
and storage; habitat environmental thermal control of temperature and humidity; all
waste collection, sterilization, storage, and reclamation, where appropriate; and
Life Support Systems for Manned Mars Missions, Overview
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waste water recovery, processing, storage, and purification for crew consumption.
The sheer weight of transporting all these items during the journey and the logistics
of safely storing and/or producing them in an extraterrestrial environment are of
great concern to space agencies and the space industry. A key issue for the planning
of any mission will always be the number of crew members assigned to an
interplanetary space mission as this number will be an essential part of the algorithm
used to calculate essential resources. Researchers have been considering the number
of astronaut crew to go as between four and six space travelers. This number is seen
as vital information by many scientists as it will dictate the quantity needed of each
life support element defined by ALS. Therefore, the first step for an interplanetary
mission is to create an inventory of consumables that will be necessary for a
successful return trip to Mars, considering the journeys and planet-based time and
any recycling or regeneration techniques and methods that will be available
(MacElroy et al. 1992; Rapp 2006; Barratt and Pool 2008).
Calculating the Ins and Outs
Each ALS element has to be carefully quantified per-crewmember-per-day and then
multiplied by the total number of astronauts. It is equally important to tabulate the
amount of waste per each type, which can range from disposable (paper, clothing,
food waste) to organic materials produced by the astronauts (feces, urine, expelled
carbon dioxide). It is estimated, for example, that each crew member will consume
0.617 kg of food, 3.91 kg of water, and 0.84 kg of oxygen every day of a mission,
while the daily production of waste will be around 5.4 kg, including liquids, solids,
and carbon dioxide).
These calculations will provide the needed amount of ALS elements to be
transported for a space mission, especially a long-term one, and also reflect the
scale of the waste produced, which must be managed, processed, and regenerated
where possible. On the ISS much waste is dealt with by storing for return to Earth or
by dumping it overboard. Other solutions to the waste issue have been studied and
proposed over the years. Some researchers have considered exposing the waste to
high temperatures and pressures, in a process called pyrolysis, to generate useful
by-products. However, such a method has the need for large amounts of power,
which is an important limitation when considering a remote, confined, and isolated
environment, such as found on a spacecraft (Rapp 2006).
In a simplistic way, humans are main consumers of oxygen and biomass and
major producers of carbon dioxide and waste. This process needs to be built upon to
utilize the waste products and regenerate wherever possible useful resources. For
example, human waste products could be used directly by plants (nutrients and
carbon dioxide) or fermented by microorganisms into minerals and other nutrients,
which in turn could serve as resource for plant growth (Rapp 2006).
A major part of the solution would be the development of sophisticated technologies that could be applied to the recycling and transformation of some of these
elements that will be essential for an adequate life support system for space crew
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during an interplanetary mission. In other words, these fundamental elements should
be provided in a regenerative form and not as consumables. If all or at least some
could be reliably recycled or regenerated, it would add to crew resources and safety,
and ultimately to the potential longevity and success of the mission. A trip to Mars
must begin with the minimal needed amount of food, water, and biological material,
such as plant seeds and microbial cultures, dried or cryopreserved, for recycling and
generation of new edible biomass in order to establish a self-sustainable ecosystem.
In addition, focus must be given to creating a regenerative system that is of longduration and as self-sustaining as possible; failure-free functioning with the minimal
need for spare parts and expendables will be essential. A life support system with a
very high recovery percentage for resources will be of less benefit if it has a poor
reliability rate, and therefore, the right balance must be found between the two, i.e., a
system with a recovery percentage of 99% and reliability of 90% is less preferable
than a system with a recovery rate of only 90% but reliability of 99% (Rapp 2006;
Seedhouse 2009; Shkedi 2009).
Bioregeneration as a Solution
The research for development of a life support system suited to a Mars mission is
already well under way. Consideration must be given to the resources taken to the
planet, as well as the potential for utilization of the natural resources to be found on
the planet itself. A bioregenerative life support system (BLSS) will ideally perform
all of the basic functions required by a life support system in a manner involving
natural regenerative processes that produce basic life support consumables, including atmosphere revitalization, water and organic waste recycling, and food production. Current examples of research in this field include the European Space Agency
managed MELiSSA (Micro-Ecological Life Support System Alternative) project,
initiated in 1989; a collaborative research involving numerous European, Canadian,
and other research institutions, such as the University Autonoma of Barcelona,
University of Guelph, University of Ghent, and University of Clermont Ferrand;
the Controlled Environmental Life Support System (CELSS) program, initiated in
1978 by NASA; and the prototype Lunar Greenhouse (LGH) project involving the
University of Arizona, USA, backed by NASA funding, and the University of
Naples Federico II, Italy with the help of ESA funding, among others (MacElroy
et al. 1992; Rapp 2006; Shkedi 2009; NASA 2015).
Looking at one of these systems in more detail provides the basic concept of the
closed loop that is created, with the astronaut crew at the center of a process that
mimics an ecosystem concept to take waste products and air pollutants and pass
them through several steps until converted back to usable water, oxygen, and food
products.
The MELLiSA Loop (ESA 2015) comprises of the interconnection of four
distinct compartments, with the last being split into two sections (Fig. 1): Compartment 1- Liquefying, Compartment 2- Photoheterotrophic, Compartment 3- Nitrifying, Compartment 4- Algae and Higher Plants. The Loop begins with the collection
Life Support Systems for Manned Mars Missions, Overview
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Fig. 1 Diagram of the MELiSSA Loop (Micro-ecological Life Support System Alternative), a
European Space Agency collaborative project. Image: ESA
of waste products in Compartment 1 where they are anaerobically transformed
(at high temperature, 55 C) into more usable forms, such as carbon dioxide,
hydrogen, ammonia, volatile fatty acids, and minerals, through microbial degradation using thermophilic fermentative bacteria. Compartment 2 eliminates the liquid
waste products of Compartment 1, primarily the volatile fatty acid, as well as carbon
dioxide and hydrogen, through photoheterotrophic organisms. Compartment 3 converts the ammonia from wastes into nitrates that can be used as a source of nitrogen
for higher plants and more easily used by autotrophic algae/bacteria. Finally, Compartment 4 is split into two sections: algae compartment colonized by the
cyanobacteria Arthrospira platensis and a Higher Plant compartment, both essential
for the production of oxygen, water, and food. However, the simplistic nature of this
description does not take account of the as yet unknown implications of operating
such a system in an environment of reduced gravity and potentially increased
radiation exposure. Further research is required to test the effects of spaceflight-
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related stress on the bacterial strains used in the process, and consideration needs to
be given to the genetic evolution that is possible during long-term culturing.
Furthermore, the composition of waste products may well be affected and changed
over time by residence in a Martian environment, leading to altered bacterial
responses and changes in the ecological cycle.
In Situ Resource Use: An Important Addition
The surface of the planet of Mars is known to be very different from that of Earth,
and although it does not offer the same abundance of accessible resources that has
sustained mankind, it does have natural resources that could be utilized to assist
long-term settlement. The use of in situ resources will make the establishment of
extraterrestrial exploration more financially viable by minimizing the materials
carried from Earth and by developing advanced, autonomous devices to make best
use of these available in situ resources (Rapp 2006). On-site production of life
support consumables could not only extend mission duration but also have the
potential to provide scientific returns. An important aspect will be the ability of
astronauts to deal with the toxic atmosphere of the planet and find ways to extract in
situ from its useful resources. The Martian soil contains oxygen in its rocks, as
confirmed by drill samples taken by NASA’s Curiosity robotic rover, which landed
in the Gale Crater on Mars on 6 August 2012. It is, however, a difficult process to
remove this gas from the soil of the planet and a more likely alternative will be to
take advantage of the atmosphere of Mars that is very rich in carbon dioxide – a
potential source of carbon and oxygen. The atmospheric pressure on the planet is
around 100 times less than found on Earth, with the average pressure on Earth being
29.92 inches of mercury as opposed to an average of 0.224 inches of mercury on
Mars. This will require the air to be first compressed by a factor of 100 or more to
then be processed. A reducing agent such as hydrogen will be needed to separate the
carbon from the oxygen in the carbon dioxide, in effect producing CH4 and O2 when
reacting with the CO2. This process, however, will not be simple as hydrogen is a
rare gas on Mars (Rapp 2006).
A possible solution could be to mine the surface of Mars to retrieve any available
water. Although no surface water is present, it is known that subsurface ice exists
beneath the planet polar caps and surfaces, and this could be used to supply water for
crew needs, while also being used to enable the atmosphere to be compressed to
create carbon, hydrogen, and oxygen (Seedhouse 2009).
Making Fiction a Reality
In summary, our survival depends on the provision of three basic commodities – air,
water and food, preferably in quantities that enable our physiology to thrive.
Whether we find ourselves on the Earth, the Moon, or millions of miles away on
Mars, these needs are the same and must be met on a daily basis. The explorer
Life Support Systems for Manned Mars Missions, Overview
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instinct in mankind originally drove us to leave the comfort and safety of our homes
and communities, to sail across vast oceans and face new challenges in unknown
lands. This same instinct has made us look up to the stars in the dark night skies and
wonder what lies beyond. Within our solar system, Mars is considered the most
Earth-like planet, although in reality the environment on Mars is far more hostile
than ours due to important differences in temperature, atmospheric pressure, and
gravity. Nonetheless, it is to the “red planet” that we have dreamed of traveling, in
literature from such books as Journey to Mars by Gustavus W. Pope in 1894 and The
Martian Chronicles by Ray Bradbury in 1950, and in numerous films, such as Abbott
and Costello Go To Mars in 1953 and Robinson Crusoe on Mars in 1964, to name
but a few (Lamont 1953; Haskin 1964; Pope 2008; Bradbury 2012). Travelling to
Mars is no longer solely in the realms of science fiction; several initiatives have been
proposed in the last 50 years, both manned and nonmanned, and valuable knowledge
has already been gained from the Mars exploration rovers that have successfully
landed on the planet surface. A manned voyage to Mars and time spent on the planet
surface is still an enormous challenge, despite the ongoing research. Many obstacles
have yet to be overcome, including the continued development of closed-loop
regenerative life support systems to ensure astronaut survival and a means to avoid
excess radiation exposure; however, we are nearer to achieving the goal of a
manned-mission to Mars than at any other time in our history, and continued
scientific advances will undoubtedly open up exploration of this new frontier
(MacElroy 1992).
Cross-References
▶ Classification and Overview of Spacecraft Life Support Systems
▶ Designing a Closed Ecological Life Support System for Plants, Overview
▶ Examples of and Rationale for Bioregenerative Life Support Systems
▶ Future Life Support Systems, Overview
▶ Human Habitability Considerations, Overview
▶ Life Support Systems of the International Space Station
▶ Micro-Ecological Life Support Alternative (MELISSA), Overview
▶ Mission Duration and Location: Effects on Mass and Cost
▶ Short and Long Duration Mission Human Factors Requirements
References
Barratt MR, Pool SL (eds) (2008) Principles of clinical medicine for space flight. Springer,
New York
Bradbury R (2012) The martian chronicles. Simon & Schuster, New York
ESA - MELiSSA Loop (Microecological Life Support System Alternative) http://www.esa.int/
spaceinimages/Images/2009/07/Melissa_loop_diagram. Accessed 6 Apr 2015
Haskin B, dir (1964) Robinson Crusoe on Mars. Perfs. Paul Mantee, Victor Lundin. Aubrey
Schenck Productions
12
T. Russomano
Lamont C, dir (1953) Abbott and Costello Go To Mars. Perfs. Bud Abbott, Lou Costello. Universal
Int. Pictures
MacElroy RD, Kliss M, Straight C (1992) Life support systems for Mars transit. Adv Space Res 12
(5):159–166
NASA International Space Station, Environmental Control and Life Support System. http://www.
nasa.gov/sites/default/files/104840main_eclss.pdf. Accessed 6 Apr 2015
Pope GW (2008) Journey to Mars. Wildside Press, USA
Rapp D (2006) Mars Life Support System. International Journal of Mars Science and Exploration,
Mars 2, 72–82, 2006
Rask J, Vercoutere W, Navarro BJ, Krause A (2012) NASA space faring: the radiation challenge
introduction and module 1: radiation educator guide. BiblioGov, USA
Russomano T, Dalmarco G, Falcão FP (2008) Synthesis lectures on biomedical engineering #18 the effects of hypergravity and microgravity on biomedical experiments. Morgan & Claypool
Publishers, Connecticut v. 1. 70p
Seedhouse E (2009) Martian outpost: the challenges of establishing a human settlement on Mars.
Springer Praxis Books, New York
Shkedi BD (2009) Lessons learned from the International Space Station (ISS) Environmental
Control and Life Support System (ECLSS) water subsystem. SAE Int J Aerosp 1(1):78–83
Vakoch DA (ed) (2011) Psychology of space exploration. NASA History Series SP-2011- 4411,
Washington, DC