ROOM
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Astronautics
Recycling air would be a good supplement to in
situ resource utilization (ISRU) but refinements
in recycling technology would be necessary as
current technology is impractical on very long-
duration missions. The average temperature on
Mars is -63C so there would also be a need to
maintain Earth-like temperatures inside habitats.
Unlike on previous human space missions, which
have operated almost exclusively in vacuum and
therefore were more concerned with radiating
excess heat than retaining it, the Mars colony would
require systems to distribute heat throughout
the habitat as well as insulate the environment to
maintain a comfortable temperature for human
living. The environmental support system would also
need to be capable of filtering micro pollutants, such
as dust from outside, trace amounts of synthetic
compounds, etc, out of the colony’s air and water.
The amount of water necessary to support
a permanent human colony on Mars would
be prohibitively heavy if brought from Earth.
Fortunately, water is not only naturally available on
Mars, and not exclusively at its poles, but is relatively
abundant; frozen water comprises between 1.5 and
three percent by mass of the Martian regolith, and
this water can be extracted simply by heating it up.
It could very well be easier for the Mars colony to
produce water than to recycle it.
As mentioned, the technology needed
to recycle sufficient volumes of water for
a permanent Mars colony would require
significant further development; as an example,
current water recycling and waste disposal
systems used on the International Space Station
(ISS) are not designed to handle menstrual
range tolerated by the human circadian rhythm,
the general need to remain inside the Martian
habitat for most hours of the day will limit the
ability of colonists to align their circadian rhythms
with the Martian sol. Scheduled day and night
periods inside the colony would therefore be
necessary to prevent circadian disruptions.
It would also be necessary to develop reasonable
schedules and workloads for colonists. Operating
the colony and its systems will require constant,
around-the-clock work and observation, and
consequently it will be necessary to maintain
at least two shifts with inverted work/rest
schedules. If those assigned to a particular shift
were unpredictably transferred to the other shift,
or made to work beyond their regular shift, the
resulting circadian disruptions would very likely
cause them to perform below their optimal level.
Life support
Life support systems for human spaceflight have
historically been relatively simple and requirements
for a Mars colony will include power, environmental
support, clean water, waste disposal, food
production and medical treatment facilities. Any
permanent Mars colony will need to use resources
available in situ or recycle, as regular deliveries of
food and water will not be practical.
Arguably, power systems will be the most critical
system in the Mars colony because, without it, other
systems needed to support human life would fail.
Solar power is one option, although due to Mars’
distance from the Sun and environmental conditions,
the surface area of the requisite solar arrays would
need to be impractically large.
Nuclear power, either through fission or
radioisotope emission, would likely be more efficient
in terms of mass than solar power and more reliable,
although it clearly presents other challenges. In
practice, a combination of both nuclear and solar
power might be prudent for a Mars colony.
Multiple systems will be needed to monitor
and maintain the colony’s internal environmental
conditions. The native Martian atmosphere
is largely composed of carbon dioxide and
it maintains a pressure only one percent of
Earth’s; atmospheric systems would therefore
need to maintain Earth-like internal conditions,
approximately 78 percent nitrogen and 21 percent
oxygen, at roughly 101 kilopascals of pressure, in
spite of the external environment.
Local resources could be used to extract oxygen
and other necessary atmospheric components
in situ from the Martian environment instead of
bringing them from Earth.
Global map of Mars
showing estimated
radiation dosages from
cosmic rays reaching the
surface, based on
cosmic-radiation
measurements by the
Mars radiation
environment experiment
on NASA’s Mars 2000
Odyssey spacecraft, plus
information about Mars’
surface elevations from
the laser altimeter
instrument on NASA’s
Mars Global Surveyor.
Water is not
only naturally
available on
Mars but is
relatively
abundant
NASA/JPL
