Tuesday, September 8, 2020

Zero Gravity and the Physically Disabled




In one of Robert Heinlein’s lesser known stories, Waldo, there was a gifted recluse named Waldo Farthingwaite-Jones, who was born handicapped, a victim of myasthenia-gravis.  He was also a mechanical genius, but could not adjust to society.  He invented a sort of mechanical hand, the “‘Waldo F. Jones’ Synchronous Reduplicating Pantograph,” and became a rich man from this invention.  

This handicapped genius was then able to build a space habitat orbiting the Earth, serving as his home and workshop in zero-gravity.  Because of the zero gravity environment, Waldo was able to fully function his entire body, his arms, legs, back, without any trouble or pain.

Things happen, and I won’t tell you the rest of the story (you’ll have to read it yourself) but the concept of a handicapped person in zero-g being able to fully function I find fascinating, and it has been shown to work in real life.


A handicapped person on Earth, with no use of his or her arms, legs, back, regardless of what disease he’s suffered or what injury he’s experienced, will be able to fully function in a zero-g environment.  Living with no gravity for a long period of time has serious drawbacks that are detrimental to the human body, but that will be covered, along with ways in which we can deal with this situation. 

Zero gravity in space is no handicap to a physically disabled person.  A person with no legs will have no problem thriving in zero-g.  Amputees can have strength and dexterity, and new types of prosthetics can allow tasks beyond the powers of five fingers as described in Heinlein’s Waldo.

When a person is unable to move their arms, legs, or has a spinal injury, it is because their entire body is fighting against the force of Earth’s gravity.  They are too weak, physically, so the force of gravity holds their muscles down, rendering the entire body unable to function.  There are times when the physically disabled person uses prosthetics, and is challenged to move his or her arms and stand on his legs.  The brain rewires itself adjusting to these function.

In zero gravity, everything changes.  There is no gravity to hold the disabled person down.  Their muscles free up, he or she is able to move about, the spinal cord injury being irrelevant, and they can move their arms and legs, being able to control the direction in which they are floating, probably better than a normally functional human, for that particular human has to adjust and learn to control his or her limbs, while the disabled, fighting Earth’s gravity all his life and using prosthetics, already is able to do so.


Experiments have been performed on the disabled using an airplane capable of replicating the zero-g environment.

One example of this occurred in August, 2017 where the European Space Agency (ESA) sponsored a group of eight disabled kids on a parabolic airplane flight replicating the zero-g environment.  

This process is common as the first step we are now taking in space tourism.     Tourists board a jet where the passenger section has no seats, but are strapped to the floor.  The plane takes off, and at a certain height, flies up at a steep up.  The plane then reaches a certain height and descends at the same angle, all in the form of a parabola, where the passengers float around the cabin and enjoy the sensation, floating around and performing flips and other feats giving them thrills.  The plane repeats this feat several times before the tour ends.  With some people, the repetition causes them motion sickness, hence the nickname “vomit comet.”

On August 24, 2017, (this is but one example;  these tours occur frequently), eight handicapped children, along with six ESA astronauts and ESA Flight Director General Jan Worner got to experience this phenomena, just for the eight children.  As the plane took off and made its parabolic curve, the children experienced zero gravity and everyone had fun, their handicaps not withstanding.  They also participated in experiments to illustrate the effects of zero-gravity on different states of matter, such as light a candle to see how the flame would react, mixing liquids of different densities that normally don’t mix in Earth gravity, and play games like ping pong with water bubbles.

The ESA sponsored the initiative, and Novespace organized the parabolic flight and Reves de Gosse (Kid’s Dream) arranged the project itself, culminating in the zero-g flight.  (Cofield, Cara;  “Kids with Disabilities Float Like Astronauts in Gleeful Flight,”  www.space.com,  August 25, 2017.). 

You can also see the video of the flight itself at mirror.co.uk/science/esa-gives-eight-children-disabilities-11336750.


Astronauts from the International Space Station (ISS) stated “that in floating around, their legs would just get in the way” and “rookie astronauts have come onboard the ISS and started knocking things around because they don’t know what to do with them (their legs).”

One disabled student asked an astronaut if a person like him needed a wheelchair in space.  The answer he got was,  “you have to get use to controlling your body in weightlessness - but certainly no need for a wheelchair as far as I can tell.”  (www.bbc.com/news/uk-england-wiltshire-33323870;  “Disabled Student Inspired by Astronaut Tim Peake”)


Even the blind can handle space, especially in bright spots a person with normal vision couldn’t handle, or in the event of malfunctioning lights on a space vehicle, factory, or habitat.  

When a human acquires a handicap, any handicap, the brain rewires itself to adjust the human body to that handicap, as if the body had that natural function all along.  (https://space.nss.org/disability-can-be-a-superpower-in-space/,  “Disability Can be a Superpower in Space.)

The blind person is attentive to his other senses, especially to his hearing, so he can pick up sounds such as a bird flying, hearing the flapping of its wings that others would not normally notice.

According to Sheri Wells-Jensen, who has written an article in Scientific American titled “The Case for Disabled Astronauts,” (May 30, 2018, blogs.scientificamerican.com/observations/the-case-for-disabled-astronauts/), not having a disabled person on a space station/factory/habitat could be a disadvantage.  

For example, let’s say a blind astronaut is on a space station.  An accident occurs on the station, where all the lights go out and it’s totally dark, and no one can repair the life support system because of no lighting.  A blind astronaut, should he know the location of a flashlight, will be able to go there and directly retrieve the flashlight and work can commence on repairs.  A sighted astronaut, in the dark, will have to adjust to the environment before he can find the flashlight and even then, may have trouble finding it.  In a situation like a fire, as on the Russian space station Mir, that occurred in 1997, there may not be much time to adjust and look for the lights.

The blind astronaut, because of his lack of sight would not be bothered by the darkness, or by occluding smoke in the event of a fire.  The astronaut would go directly to retrieve the flashlight and any other needed device, right away, saving valuable time.

Blind astronauts, depending on their training, will be able to work on any system in the dark in an emergency while other will have to adjust their sights.  Only when the flashlight are retrieved will the sighted astronauts be able to repair the system.  It is possible for a blind astronaut to be an expert in the field of engineering, so he will be able to fix systems in the dark, or when the sun is so bright other astronauts would not be able to see well.


There is also a case for deaf astronauts.  (Eveleth, Rose;  “It’s Time to Rethink  Who’s Best Suited for Space Travel,” Wired, January 27, 2019, wired.com/story/its-time-to-rethink-whos-best-suited-for-space-travel/).

In 1962, an experiment was performed by the U.S. Navy on 11 men who were deaf, 10 of them due to spinal meningitis.  This disease damaged their inner ear, including their vestibular systems.  This very system to mainly responsible for motion sickness.

For nearly a decade, these men were put through strenuous tests, to help test the feasibility of human spaceflight.  This occurred in the 1960s, before we knew whether or not the human body could withstand a trip beyond Earth’s atmosphere.  

In one test, four of the men spent 12 straight days inside a 20 foot room that rotated constantly.  In another experiment, they were sent out on a boat in very rough waters off the coast of Nova Scotia.  The four deaf men sat around playing cards, but the researchers got seasick and had to cut short the trip so they could go home and recover.  The seven other deaf men went up in the “vomit comet.”  In all the experiments, none of them ever got sick.

These men were recruited from Gallaudet College, now University, in Washington, D.C. and they were chosen because of the damage to their inner ear, where, as a result, could not sense up and down.

They never became astronauts but their work “made substantial contributions to the understanding of motion sickness and the adaptation of space flight,” wrote Hannah Hotovy, of the NASA history division.

These students became know as the Gallaudet Eleven, after their college.  One member, Harry Larson, was quoted as saying, “We were different in a way they (meaning NASA) needed.”


Adjusting to zero gravity in space is not an easy process.  The body has to be maintained with diet, exercise, and the intake of vitamins and minerals, on a permanent basis.

Dr. Iddo Magen of the Davidson Institute of Science Education has written a paper on this problem, and I will quote him, along with others later noted, in the following section.  (Magen, Dr. Iddo, “The Dangers of Zero Gravity,”  Davidson Institute of Science Education,  https://davidson.weizmann.ac.it/sciencepanorama/dangers-zero-gravity, February 27, 2017.)

I have mentioned motion sickness when NASA has experimented with the deaf, where an astronaut can become nauseous, and vomit.  It has been found that it is due to the body’s physiological processes, involving the ability to adapt to the sudden weightlessness in space.  The internal fluids, in balance on Earth become unbalanced in space with complete adjustment, the astronaut gets sick.  The effects are mostly temporary, usually from a few hours to three days as the body adjusts, but there have been cases on the ISS where sickness can be long-term.

Long term exposure to zero-g causes multiple health problems.

Fluid distribution in the body make up 60% of the body’s weight and accumulates in the lower part of the body in normal Earth gravity.  Our body’s systems then distributes and balances the flow of blood to the heart and brain, in a stable level to assure just enough blood and other fluids flow to the proper parts as needed.

However, in the absence of gravity, these systems continue to function, but the fluids accumulate in the upper part of the body rather than the lower part, causing a person’s face to puff up.  There is a reduction of blood volume, red blood cell quantity, and cardiac output of blood (it decreases) because of lower demands on the cardiovascular system.  However, this is normal and the human body is still able to fully function in space.

There are, however, problems in balance as well as a loss of taste and smell.  Their vision blurs for a few days.  The brain can adjust the image, and the body can adjust to the new environment, but once the astronauts return to Earth, the body again has to readjust to Earth’s gravity causing an inability to stand for more than 10 minutes at a time.  Fortunately, the body readjusts over time.


There are other adverse effects, also.

Because there is no weight load on the back and leg muscles, they begin to weaken and shrink.  Without exercise, astronauts may lose up to 20% of their muscles within five to 11 days.

Bone loss (atrophy) suffers most of all.  The rate of bone loss in zero-g is 1.5% per month, compared to 3% per 10 years on Earth, and there have been situations where there was up to a 50% muscle mass loss on long term space missions.  This loss mostly affects the lower vertebrae of the spine, the hip joint, and the femur.  All in all, bones become brittle.

On Earth, there is a balance between bone builder cells and bone destroyer cells, and they complement each other.  In zero-g, the increase in activity of bone destroyer cells are seen, and the bone decomposes into minerals that are dissolved in the blood and absorbed in the body.

The pelvic are carries most of the load under normal conditions, so bone destroyer activity greatly affects this area.


Elizabeth Howell in space.com stated, “Calcium in bones secrets out through urine.  As the bones weaken, astronauts are more susceptible to breaking them if they slip and fall, just like people with osteoporosis.”  (Howell, Elizabeth, “Weightlessness and Its Effect on Astronauts,”  www.space.com/23017.weightlessness.html, December 16, 2017.

Astronauts who remain in space for three to four months do regain their bone density after a period of three to four years on Earth.  On the Moon, it may be less.  That has yet to be proven.


On the ISS, the muscle and bone loss is minimized by an exercise program, done by each astronaut six days a week, on three different machines:  a treadmill, a bicycle, and a weightlifting machine.  Each astronaut exercises for a total of two and a half hours per day.

One hour is spent lifting weights (air pressure) and 45 minutes is on the bike, and another 45 minutes on the treadmill. 

Weight setups uses differential pressure by way of two evacuated cylinders.  Each cylinder is a piston, and acts like a syringe, creating air pressure.  These cylinders act like a simulated weight in space, pulling again the force they create.  (Grush, Loren;  “How Do Astronauts Exercise in Space?”  The Verge, December 23, 2019,  the verge.com/2017/8/29/16217348/nasa-iss-how-do-astronauts-exercise-in-space/). 

This is known as an Advanced Restive Exercise Device, and is capable of exercising all major muscle groups, focusing on squats, dead lifts, and calf raises, which helps the crew maintain their strength and endurance.

There is a personalized plan for each astronaut, because of their different physical make-ups.  (“The International Space Station Advanced Restive Exercise Device;”  NASA Technology Transfer Program, technology.nasa.gov/patent/MSC-TOPS-59/)

The Combined Operational Load Bearing External Resistance Treadmill (COLBERT - Yes, it’s named after Stephen Colbert) requires that the astronaut be loaded down to the treadmill’s surface, because of zero gravity.  One has to be harnessed and connected, with the help of bungee cords.

The astronaut is weighted down as he runs in place on the treadmill.  This is good for both the legs and the cardiovascular system. (tumbler; NASA; “Exercising in Space,”  nasa.tumbler.com/post/136706596374/exercisinginspace).

The Russians also have a treadmill in their own separate module on the ISS, as well as a bicycle (VELO Ergomoeter Bike (VB-3)), Cycle Ergometer with Vibration Isolation System (CEVIS).

The “bicycle” is similar to an actual bicycle or an exercise bike, but is mounted to the wall and has no seat.  The device is harnessed to the wall and the astronaut stands while pedaling.  The astronaut then pedals for about 45 minutes.

This exercise keep the legs in shape, in order to walk once an astronaut returns to Earth.  It also helps the heart rate and the circulatory system. (“Cycling on the International Space Station with Astronaut Doug Wheelock;”  YouTube;  May 11, 2013).


Mark Springel, a research assistant of the Department of Pathology at Boston’s Children’s Hospital writes,  “all human organ systems are affected by gravity’s absence.  The body is highly adaptive and can acclimatize to a change in gravitation environment, but the physiological adaptations may have pathological consequences, or lead to a reduction in fitness that challenges a space traveler’s ability to function normally upon return to Earth.  (Springel, Mark;  “The Human Body in Space: Distinguishing Fact from Fiction,”  Harvard University, The Graduate School of Arts and Sciences,  SITN-Science in the News;  sitn.hms.harvard.edu/flash/2013/space-human-body/,  July 20, 2013.)

An astronaut does recover, but depending on their time in space, it can take up to four years to recover on Earth.


In this paper, we are covering spending a lifetime in space, including dying there.  What would the overall effects of the body be?  Some of it have been discussed.  Can a human be able to spend a lifetime in zero-g, dealing with he adverse effects?  What would he or she have to do to keep their body safe from harm?

There are ways around all this; diet, exercise, protection from radiation in the form of cosmic rays and solar flares when they occur, which is rare, and development of new technologies that can accommodate zero-g workers.

For diet, the main problem of bone loss is a decrease of calcium.  There is plenty of that element available.  Whenever zero-g workers eat, calcium can be added to their food, rather then taking it in pill (which can and should be available), along with other needed vitamins as well, some occurring naturally in the food they eat.  On Earth, sugar is added in almost all processed foods today, and though it is not a good thing to do, this very concept can be applied to needed vitamins to food up in space.


Exposure to an environment in space with microgravity and ionizing radiation can perturb the cardiovascular, excretory, immune, musculoskeletal, and nervous systems.  Astronauts on the ISS are mostly protected by shielding on the ISS along with Earth’s magnetic field.  This will have to change as we proceed further out into space.  Antioxidants like Vitamins A and C can also absorb radiation before causing harm to the human body.  

Cosmic rays from space are constant, originating from supernovae literally tens of thousands of light years away.   Solar flares, which are local, will occur, but one can be inside an asteroid mine for protection, or a space habitat with an efficient radiation shield.  

The Earth’s magnetic field is a big plus in protecting astronauts from radiation in cis-lunar space (the area between the Earth and the Moon).  The magnetic field protects the entire globe from cosmic and solar radiation.  This field form a bullet shaped bubble, and extends into space about 60,000 kilometers (37,500 miles) towards the sun, and 300,000 kilometers (187,500 miles) away from the sun, towards deep space.  Any space habitat within the range of 60,000 kilometers, of the Earth, which is beyond Geosynchronous Earth Orbit (37,280 kilometers or 23,300 miles) would be safe most of the time.  Shielding will still be required.

Beyond the safe zone will require more dense shielding, but resources from the Moon and near Earth asteroid could be obtained to achieve this.

The human body at work will solve a lot of problems, be it in a space factory, a mine in an asteroid (moving rocks and other heavy objects, which is easy in zero-g) or moving segments of habitats, asteroids, or any heavy object by hand rather then by mechanical arm.

In habitats, there will be exercise machines, as on the ISS, as well as sports and other activities for workers during their spare time.  There will also be rotating shifts, say, as an example, four months at a time.

In order to insure a long life and to protect the work from the adverse effects of zero gravity and radiation, the worker would work four months, spend four months on the Moon or a rotating space habitat with gravity, and then four months on again at work in zero gravity.

They would spend their off time on the Moon rather than Earth because 1) the laborer would revert back to being disabled and 2) it would take up to four years for a normal astronaut to recover, never mind the disabled worker.

The Moon has only one sixth of the Earth’s gravity, and that worker will be able to function in a much lighter gravitational environment.  The Moon’s habitats, protected by regolith, also provides shielding against radiation.


What sort of jobs will be available in zero-gravity space, or on the Moon, for the Earth disabled (phrase mine)?  The answer is simply any job that the non-disabled could do.  There will be no limitations for anyone.  The only real difference is that a disabled person is more willing to commit his or her whole life in space.  A non-disabled person, unless that person intends to settle in space permanently, and many of them will, may want to return to Earth after a few years, and someone else will have to be retrained to take his place.  This means that the company will have to spend money and time retraining that person, and they will not want that.

A disabled person may not want to return to Earth because its gravity will revert him back into the wheelchair, something he will not want to do.

In space, the Earth disabled will have the same types of jobs like everyone else.  They will be no handicapped people up there.  

Let’s go over the list.

Labor jobs will be available.  Jobs such as mining the Moon and asteroids, holding drills and other equipment, moving rocks and minerals.

Construction workers, constructing new habitats in space, be they passenger terminals, space factories, space stations, space living quarters, and doing repairs on them, especially when the repairs require that worker to go out in space to perform it.

Helping to assemble these habitats by hand and making the proper connections.

Operation of heavy equipment, be it in space, on an asteroid, or on the Moon.

Working in space factories where zero gravity is essential in manufacturing a product.  This could be metals, crystals, chemicals, medicines, alloys, or anything else.  These workers here would be professionals with a college education, up to a doctorate.

Being a scientist, experimenting with new materials in zero gravity.

Life sciences, which is working with human and other biological organisms, and observing how they function in zero-g, and how many adverse effects of zero-g on humans can be resolved.  This is very important, with more of the human population coming into space, there must be applications for their bodies to remain healthy.

Piloting spaceships around space for long periods of time.


Space is the perfect place for the disabled, where disability will be confined to Earth, or be a thing of the past.

With a broken spine or missing limbs, these people will simply be different, but equally important in helping to maintain stability, be it economic, technical, or otherwise, in this new spacefaring civilization.


Space will offer a lot of opportunities for the physically disabled from Earth.  It has been proven that zero gravity can make a person’s body fully function, as demonstrated in this paper.

Should a handicapped person decide to spend the rest of their lives in space, be it labor or working with computers, life will be demanding, having to keep their bodies in shape against zero-g, but if they are willing to adjust to the demands and self-discipline required, they will have productive and fulfilling lives.


Alastair Browne