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Real NASA Technologies in 'The Martian'
Mars has held a
central place in human imagination and culture for millennia. Ancients marveled
at its red color and the brightness that waxed and waned in cycles over
the years. Early observations through telescopes led some to speculate
that the planet was covered with canals that its inhabitants used for
transportation and commerce. In “The War of the Worlds”, the writer H.G. Wells
posited a Martian culture that would attempt to conquer Earth. In 1938, Orson
Welles panicked listeners who thought they were listening to a news broadcast
rather than his radio adaptation of Wells’s novel.
The real story
of humans and Mars is a little more prosaic but no less fascinating. Telescopes
turned the bright red dot in the sky into a fuzzy, mottled disk that gave rise
to those daydreams of canals. Just 50 years ago, the first photograph of Mars from a
passing spacecraft appeared to show a hazy atmosphere. Now decades of exploration
on the planet itself has shown it to be a world that once had open water, an essential
ingredient for life.
The fascination
hasn’t waned, even in the Internet Age. A former computer programmer named Andy
Weir, who enjoyed writing for its own sake and posted fiction to his blog,
started a serial about a NASA astronaut stranded on Mars. The popularity
ultimately led him to turn it into a successful novel, “The Martian”,
which has been made into a movie that will be released in October 2015.
“The Martian”
merges the fictional and factual narratives about Mars, building upon the work
NASA and others have done exploring Mars and moving it forward into the 2030s,
when NASA astronauts are regularly traveling to Mars and living on the surface
to explore. Although the action takes place 20 years in the future, NASA is
already developing many of the technologies that appear in the film.
Want to see how movie technology compares to actual NASA technology?
Want to see how movie technology compares to actual NASA technology?
On the surface
of Mars, Watney spends a significant amount of time in the habitation
module -- the Hab -- his home away from home. Future astronauts who
land on Mars will need such a home to avoid spending their
Mar
tian sols lying on the dust in a spacesuit.
tian sols lying on the dust in a spacesuit.
At NASA Johnson
Space Center, crews train for long-duration deep space missions in the Human Exploration Research Analog (HERA).
HERA is a
self-contained environment that simulates a deep-space habit. The two-story
habitat is complete with living quarters, workspaces, a hygiene module and
a simulated airlock. Within the module, test subjects conduct
operational tasks, complete payload objectives and live together for 14
days (soon planned to increase to up to 60 days), simulating future missions in the isolated
environment. Astronauts have recently used the facility to
simulate ISS missions. These research analogs provide valuable data
in human factors, behavioral health and countermeasures to help further NASA’s
understanding on how to conduct deep space operations.
Plant Farm
Today,
astronauts on the International Space Station have an abundance of food
delivered to them by cargo resupply vehicles, including some from commercial industries. On Mars, humans would
not be able to rely on resupply missions from Earth – even with express
delivery they would take at least nine months. For humans to survive on Mars,
they will need a continuous source of food. They will need to grow crops.
Water Recovery
Watney turns the
Hab into a self-sustaining farm in “The Martian,” making potatoes the first
Martian staple. Today, in low-Earth orbit, lettuce is the most abundant crop in
space. Aboard the International Space Station, Veggie is a deployable fresh-food
production system. Using red, blue, and green lights, Veggie helps plants grow
in pillows, small bags with a wicking surface containing media and
fertilizer, to be harvested by astronauts. In 2014, astronauts used
the system to grow “Outrageous” red romaine lettuce and just recently
sampled this space-grown crop for the first
time. This is a huge step in space farming, and NASA is looking to expand
the amount and type of crops to help meet the nutritional needs of future
astronauts on Mars.
There are no
lakes, river or oceans on the surface of Mars, and sending water from Earth
would take more than nine months. Astronauts on Mars must be able to create
their own water supply. The Ares 3 crew does not waste a drop on Mars with
their water reclaimer, and Watney needs to use his ingenuity to
come up with some peculiar ways to stay hydrated and ensure his survival on the
Red Planet.
On the
International Space Station, no drop of sweat, tears, or even urine goes to
waste. The Environmental Control and Life Support System recovers and
recycles water from everywhere: urine, hand washing, oral hygiene, and other
sources. Through the Water Recovery System (WRS), water is reclaimed
and filtered, ready for consumption. One astronaut simply put it, “Yesterday’s
coffee turns into tomorrow’s coffee.”
Liquid presents
some tricky problems in space. The WRS and
related systems have to account for the fact that liquids behave very
differently in a microgravity environment. The part of the WRS that
processes urine must use a centrifuge for distillation, since gases and liquids
do not separate like they do on Earth.
NASA is
continuing to develop new technologies for water recovery. Research is
being conducted to advance the disposable multifiltration beds (the
filters that remove inorganic and non-volatile organic contaminants) to be
a more permanent component to the system. Brine water recovery would
reclaim every drop of the water from the “bottoms product” leftover from urine
distillation. For future human-exploration missions, crews would be less
dependent on any resupply of spare parts or extra water from Earth
The technology
behind this system has been brought down to Earth to provide clean drinking water to remote
locations and places devastated with natural disasters.
Oxygen Generation
Food, water,
shelter: three essentials for survival on Earth. But there's a fourth we
don't think about much, because it's freely available: oxygen. On
Mars, Watney can’t just step outside for a breath of fresh
air To survive, he has to carry his own supply of oxygen
everywhere he goes. But first he has to make it. In his Hab he uses the
“oxygenator,” a system that generates oxygen using the carbon
dioxide from the MAV (Mars Ascent Vehicle) fuel generator.
On the
International Space Station, the astronauts and cosmonauts have the Oxygen
Generation System, which reprocesses the atmosphere of the spacecraft to
continuously provide breathable air efficiently and sustainably. The
system produces oxygen through a process called electrolysis, which splits
water molecules into their component oxygen and hydrogen atoms. The
oxygen is released into the atmosphere, while the hydrogen is either
discarded into space or fed into the Sabatier System, which creates water from
the remaining byproducts in the station's atmosphere.
Oxygen is
produced at more substantial rate through a partially closed-loop system that
improves the efficiency of how the water and oxygen are used. NASA is working
to recover even more oxygen from byproducts
in the atmosphere to prepare for the journey to Mars.
Mars Spacesuit
The Martian surface
is not very welcoming for humans. The atmosphere is cold and there is barely
any breathable air. An astronaut exploring the surface must wear a spacesuit to
survive outside of a habitat while collecting samples and maintaining systems.
NASA is currently
developing the technologies to build a spacesuit that would be used on Mars.
Engineers consider everything from traversing the Martian landscape to picking
up rock samples. Mark Watney spends large portions of his Martian sols (a sol
is a Martian day) working in a spacesuit. He ends up having to perform some
long treks on the surface, so his suit has to be flexible, comfortable,
and reliable.
The Z-2 and Prototype eXploration Suit,
NASA’s new prototype spacesuits, help solve unique problems to advance new
technologies that will one day be used in a suit worn by the first humans to
set foot on Mars. Each suit is meant to identify different technology gaps –
features a spacesuit may be missing – to complete a mission. Spacesuit
engineers explore the tradeoff between hard composite materials and fabrics to
find a nice balance between durability and flexibility.
One of the
challenges of walking on Mars will be dealing with dust. The red soil
on Mars could affect the astronauts and systems inside a spacecraft if tracked
in after a spacewalk. To counter this, new spacesuit designs feature a suitport
on the back, so astronauts can quickly hop in from inside a spacecraft
while the suit stays outside, keeping it clean indoors.
Rover
Once humans
land on the surface of Mars, they must stay there for more than a year,
while the planets move into a position that will minimize the length of their
trip home. This allows the astronauts plenty of time to conduct experiments and
explore the surrounding area, but they won’t want to be limited to how far they
can go on foot. Astronauts will have to use robust, reliable and
versatile rovers to travel farther.
In
"The Martian," Watney takes his rover for quite a few
spins, and he even has to outfit the vehicle with some unorthodox modifications
to help him survive.
On Earth
today, NASA is working to prepare for every encounter with the Multi-Mission
Space Exploration Vehicle (MMSEV). The MMSEV has been used in NASA’s analog mission projects to help solve
problems that the agency is aware of and to reveal some that may be
hidden. The technologies are developed to be versatile enough to support
missions to an asteroid, Mars, its moons and other missions in the future.
NASA’s MMSEV has helped address issues like range, rapid entry/exit and
radiation protection. Some versions of the vehicle have six pivoting
wheels for maneuverability. In the instance of a flat tire, the
vehicle simply lifts up the bad wheel and keeps on rolling.
Ion Propulsion
Slow and steady
wins the race, and ion propulsion proves it.
While the Dawn
spacecraft is visiting the asteroids Vesta and Ceres, NASA Glenn has been
developing the next generation of ion thrusters for future missions. NASA's
Evolutionary Xenon Thruster (NEXT) Project has developed a 7-kilowatt ion
thruster that can provide the capabilities needed in the future.
In “The Martian,”
the Ares 3 crew lives aboard the Hermes spacecraft for months as they travel to
and from the Red Planet, using ion propulsion as an efficient method of
traversing through space for over 280 million miles. Ion propulsion works
by electrically charging a gas such as argon or xenon and pushing out the ions
at high speeds, about 200,000 mph. The spacecraft experiences a force similar
to that of a gentle breeze, but by continuously
accelerating for several years, celestial vessels can reach phenomenal speeds.
Ion propulsion also allows the spacecraft to change its orbit multiple times,
then break away and head for another distant world.
This technology
allows modern day spacecraft like NASA’s Dawn Spacecraft to minimize fuel
consumption and perform some crazy maneuvers. Dawn has completed more than
five years of continuous acceleration for a total velocity change around 25,000
mph, more than any spacecraft has accomplished on its own propulsion system.
Along the way, it has paid humanity's first visits to the dwarf
planet Ceres and the asteroid Vesta.
Solar Panels
There are no
gas stations on Mars. No power plants. Virtually no wind. When it comes to
human missions to the Red Planet, solar energy can get the astronauts far. The
Hermes spacecraft in the book uses solar arrays for power, and Mark Watney has
to use solar panels in some unconventional ways to survive on Mars.
On the
International Space Station, four sets of solar arrays generate 84 to 120 kilowatts
of electricity – enough to power more than 40 homes. The station doesn’t need
all that power, but the redundancy helps mitigate risk in case of a failure.
The solar power system aboard the space station is very reliable, and has been
providing power safely to the station since its first crew in 2000.
Orion, NASA’s spacecraft that will take
humans farther than they’ve ever gone before, will use solar arrays for power
in future missions. The arrays can gather power while in sunlight to charge
onboard lithium-ion batteries. In case no sunlight is available – for instance,
if Orion were to go behind the Moon – there would still be plenty of power to
allow it to operate.
RTG
For more than
four decades, NASA has safely used Radioisotope Thermoelectric Generators (RTGs) to provide electrical power
for two dozen space missions, including Apollo missions to the Moon.
Spacecraft such as the Mars rover Curiosity and the upcoming Mars 2020 rover use an updated,
next-generation model for electrical power.
RTGs are “space
batteries” that convert heat from the natural radioactive decay of
plutonium-238 into reliable electrical power. The RTG on Curiosity
generates about 110 Watts of power or less – slightly more than an average
light bulb uses.
In "The
Martian," the crew buries the plutonium-based RTG power source for the
Mars Ascent Vehicle far away from the Hab in case of
radioactive leakage. To prevent any leak, as suggested in the
movie, Plutonium-238 has several layers of strong, advanced materials that
protect against release even in severe accidents. The RTG mostly emits
alpha radiation, which can only travel a few inches in the air and does not
penetrate clothing or human skin. It could only affect human health if it
were broken into very fine particles or vaporized, and inhaled or ingested. The
isotope is manufactured in a ceramic form, so accidentally inhaling or
ingesting it is unlikely, particularly as it does not dissolve in
liquids.
In reality, the
natural radiation environment on Mars is more extreme than the radiation
produced from an RTG. Ionizing radiation raining down on Mars from
space is far more hazardous to human health. Current Mars missions
are analyzing the Martian radiation environment so that mission planners can
design protection systems for future astronauts.
Future
explorers will need assured, reliable and durable power sources for
survival in place before they arrive. Power system options might
include a mix of more efficient radioisotope power systems, solar power, fuel
cells, and nuclear fission.
The Journey to Mars
Human
spaceflight is a dangerous business. NASA is working to send humans to Mars in
the 2030s, but there are many milestones to accomplish to ensure that
astronauts come back to Earth safely. Astronaut Scott
Kelly, currently aboard the International Space Station for one year, put it perfectly: space is hard. The
margin for error is virtually zero for every aspect of spaceflight. However, we
learn so much along the journey to Mars that furthers our
understanding of the universe, and everything we do and learn is brought right
back to Earth to benefit humanity.
Article written for NASA.gov, posted by Rin, submitted by Jeffery
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