Mars Trip Gravity Issues: an article by: GF Willmetts.

Although I’ve covered space flight in Science Fiction a while back, I haven’t really discussed the means of creating gravity on a spacecraft in our current reality for the Mars trip astronauts. Considering we already know the effects of prolonged low gravity, there is no such thing as zero-gravity, on the human body where the distribution of fluids and muscle deterioration, let alone calcium loss from the bones will make standing on Mars problematic so has to be a consideration in any space flight there. I’m choosing some fictional examples where some mention of gravity control and how it is used in the TV show or film than accepted as done. If nothing else, we can at least have some visuals, although looking at my examples, none really discuss these problems both in the now and future. Granted they aren’t supposed to but it doesn’t mean the problems weren’t addressed.

‘2001: A Space Odyssey’ showed the use of Velcro grip shoes on the shuttles for the crew to cope with reduced gravity although not on the USS Discovery, which had a rotating centrifuge to give its pilots some gravity and the later, in ‘2010’, the Soviet Leonov rotating its entire habitat for its large crew. There is no indication that any of the Russian crew hibernated in any part of the flight suggesting they are more tolerant of boredom than any American astronauts although one would have to question the limits of their food and air supply on both parts of the trip. Of course, we shouldn’t forget in the moon shuttle where Doctor Heywood Floyd reads the Zero-Gravity Toilet instructions. Having read them myself, the first 3 only apply for body functions and is pretty much how it is done today. The rest is devoted to having a shower and does make me wonder how many passengers would want to try it on a three day trip.

‘The Expanse’ TV series shows the use of what appears to be magnetic shoes although I doubt if that resolves the other body issue problems and just as a means to keep feet on the floor, although really any wall could have been a floor providing it was metal. Of course, we have to allow for budget on this. Cheaper to show a magnetic shoe than have everyone floating around.

Of course, the biggest cheats were ‘Star Trek’s Starfleet vessels, professing some form of gravity device to give a conventional ‘downward’ despite the warp drive thrust would undoubtedly crush them all to the pulp because it would exceed such a device no matter how much vector gravity it produces or how the so-called gravity compensators worked. In other words, it they aren’t squashed at warp speed then they would be crushed vertically when you consider how quickly they go to warp. Even if it could work, such an ‘attraction’ would have to be variable or any reduction in speed would have the same result.

There’s always been something that might be wrong but is actually right about the original Thunderbird 3. The base of the living quarters is in the direction of the engines firing. Fine for taking off but in space, TB3 is shown on its side, so wouldn’t it make sense for the living quarters to also be moved onto its side? However, the thrust still comes from the motors so they are still ‘upright’ and actually facing the right direction. Had Starfleet vessels done a similar thing, they might have reduced one gravity vector even if it would have been interesting filming. Logistically, showing it that way around and a simple explanation could have carried it off.

There is one other however, that is docking with Thunderbird 5. John or Alan Tracy in switching between the two TBs would have to change their orientation when they get to the TB3 entry hatch. This is something we don’t see. Then again, there are a lot of things in the original show we don’t see but take for granted.

Piers Anthony’s ‘Macroscope’ novel had a rather unique approach by liquidising its crew for transit and bringing them back to solid near arrival. Of course, anyone copying such a technique would have drawn instance comparison and a lot of faith that the mechanism would have survived to complete the resurrection as it wasn’t an instant process. It’s also a very advanced process and, as shown in the book, scary for any first-time users.

It’s isn’t just organics but mechanisms that have to survive in space flight.

The Van Vogt mile-long spaceships as used in the Null-A novels had a variety of means of space flight. The similarisation or teleportation means depended on a matrix it could home in in transit and could break-off to visit places in between and probably built up their network across the galaxy, cutting off some star systems, simply by cutting the connection. Spacecraft in transit still had their physicality and also could fly in conventional space so having the best of both worlds. It was such a big environment inside, most of the crew just had a life and were happy not to work.

A lot of the time, the need for gravity in spacecraft tends to be dismissed, passed over with a few words or ignored, given as an accepted trope as not being that important to the reader to worry about.

Picking out any SF TV or film and very few, especially in recent years fret over it but treat it as an accepted trope to the viewer or reader rather than detail it and get unstuck.

However, one thing becomes pretty obvious from the above examples is that the fictional versions don’t have a consistent way to create some form of gravity on a spacecraft and humans do need some form if they are not to have problems when they land in a gravity environment. The Moon is 1/6 and Mars is ¼ of Earth’s. It would be better for the spacecraft to rotate at different rates either way for the astronauts to adjust to these different gravities, especially after any long stays. It would make looking through any portholes very giddy although this could be compensated for by using cameras to depict the outside kept in a stationary position.

Even so, if NASA and other space agencies do choose this option, it will have to be explained to the public. There’s also a fair bet that it could be turned into a ride at the likes of Disney to experience for themselves. Don’t forget the rotating disorientating ice tunnel used in ‘The Six Million Dollar Man’ double episodes ‘The Secret Of Big Foot’ is still part of the Universal Studio Tour. Rotating the whole spacecraft is a lot less complicated than rotating only part of it and to stop it, needs only to be rotated in the opposite direction at the same rate to gradually bring it to a halt.

Doing the maths of such a rotation would depend on the size of the spacecraft. Although it might not be on the consideration for the Moon, assuming astronauts only stay there for a brief time, it would certainly have to be tried there before the trip to Mars. A wide spacecraft would certainly have a slower rotation although I do wonder if the USS Discovery’s centrifuge might be considered if only to give a partial rotation inside for the astronauts. Then again, would the public accept a spaceship looking like the Discovery? The book version was given dragonfly wings to absorb sunlight as a power source so its conceivable it might be practical that way, too. I doubt it will go too far into hibernation or an AI as an extra member of the crew.

I doubt if we’ll have anything more advanced than that. Gravity really depends on having a substantial mass to draw matter to it. When a spacecraft’s motors are firing, the force is from behind. Much of the time, any spacecraft will be coasting. I doubt if either the Moon or Mars would have enough gravitational pull to make any difference.

Equally, I doubt if anything more fanciful could be created. The laws of gravity are pretty much established. If you have any thoughts regarding micro-singularities forget it. We’ve yet to locate any and their attraction is likely to draw any mass surrounding it and wouldn’t stay micro for long. Even if it was possible and could be contained in a magnetic field, any directional attraction would still have the same effect.

You can’t just expect to have a heavy weight put under where you want the floor to be and expect people and objects to be drawn to it because it would be affected by the same low gravity as everything else. Certainly, anything not tied down is going to float around but the lessons from that have been learnt on the International Space Station.

All the Velcro and magnetic shoes in the world will not stop muscles atrophying and calcium loss from the bones. All the time in the International Space Station has proven that. What it has shown is what the body can’t use, it dispenses with. It’s just a little harder to get it all back when returning to Earth. It needs something there to ensure the body doesn’t lose any of its physical integrity. Mars having a lesser gravity helps but it would be disastrous once back home, taking months to recuperate. Hardly the look of conquering heroes on their return.

Thinking of ways within our hard science reality to generate gravity has the potential to make my own stories interesting if I go there but, on the other hand, the opportunities to explore this should be open to all and some of you might even have better ideas leading from this.

One odd speculation is to live underwater. Not like a fish, just as a buoyancy aid. It has the added bonus of absorbing radiation. This doesn’t mean the aqua-astronauts live in wetsuits throughout the voyage but their habitat within the voyage (sic) could be floating at zero buoyancy within it and a better use for the water than just storing and recycling. If this habitat can also be rotated within this water environment, then you have a gravity medium. It should be possible to have an exit into the water if needed with reduced rotation.

Of course, you could always use something more viscosity than water or even add to it to make it so but then you would have to process it to make it drinkable. Whatever the liquid is, it still has to be taken into orbit for construction. If size is a problem, then a series of ball habitats in water or whatever also allows additional space to get away from the crewmates. The only real problem is building such a large spacecraft.

Oddly, there aren’t many ways to simulate gravity in space. Before you consider hibernation, we have no proven cases of that being done yet to know it would work. Reviving on your own and not being able to get up is hardly going to help the mission.

I’m not necessarily sure if the film versions have portrayed it sufficiently. Freezing someone is risking cell damage because fluids expand when frozen and we are 90% liquid. Lowering the temperature but not enough to freeze might be possible but doesn’t solve muscular dystrophy from inaction for so long. You certainly wouldn’t want to do this on a full stomach, as in the ‘Alien’ film franchise and risk its contents going putrid by not being digested. However, on waking you would have fluids being injected as well as nutritional drinks to provide energy before even considering moving.

It has been recently been discovered that the human brain has a similar structure that allows hibernation but unused. If that could be activated then a lot of the problems would be solved. I’m not sure if I would do it for more than a few weeks at a time, simply for the need for food and exercise but it would prolong supplies. It would also present a different take on ship time. Logistically, astronaut recruitment for these long trips needs to find people capable of this hibernation to be crew.

Of course, there are biological enhancers. Stopping the body losing calcium being top of the list. Even so, even on the International Space Station, that has been proven to be problematic and not achievable, no matter how much daily exercise is taken. We could get a little more fanciful and attach some rockets to an asteroid. It wouldn’t be a fast flight but would provide some of the mass needed for a low gravity.

It does raise an interesting question as to why the likes of the International Space Station isn’t rotated to simulate gravity. Some of that is easy to answer, its in Earth orbit and not really high enough. It was also not designed to have that function and docking spacecraft would have difficulties connecting. Even so, considering the problems of minimal gravity, you would have thought that NASA and other countries would have been experimenting to sort this out rather than seeing how long humans could tolerate low gravity. Logistically, it could all be down to expense.

For those of you who’ve read the stories of Colin Kapp, one of his ideas was to put some engineers and technologists on a runaway rocket and a random selection of equipment and let them come up some with some practical solutions. A variation on this to work out a means to also give some form of gravity and they might come up with something. It could also be a disaster waiting to happen if they didn’t.

The needs of some form of gravity en flight will shape the Mars mission and the spacecraft design. It’ll be a long flight either way, more so when the astronauts arrive and are too weak to do anything. Don’t just float there. It needs some serious thought.


© GF Willmetts 2023

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Geoff Willmetts has been editor at SFCrowsnest for some 21 plus years now, showing a versatility and knowledge in not only Science Fiction, but also the sciences and arts, all of which has been displayed here through editorials, reviews, articles and stories. With the latter, he has been running a short story series under the title of ‘Psi-Kicks’ If you want to contribute to SFCrowsnest, read the guidelines and show him what you can do. If it isn’t usable, he spends as much time telling you what the problems is as he would with material he accepts. This is largely how he got called an Uncle, as in Dutch Uncle. He’s not actually Dutch but hails from the west country in the UK.

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