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In Starbound, Devon and Melissa don’t use the standard space suits that astronauts today utilize. They use what’s called a compression suit, which takes advantage of a really awesome fact, human skin is a surprisingly decent pressure vessel, especially when reinforced with thick layers of cloth. NASA actually experimented with compression suits in the 60’s, eventually developing a prototype, that, quite bluntly, looks really futuristic, but never replaced the existing suit designs due to technical difficulties. You can read about the history of space suits and the, somewhat dense, report on NASA’s experiments below.
Compression Space Suit Overview https://en.wikipedia.org/wiki/Mechanical_counterpressure_suit Compression Suit NASA Test Report\ https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720005428.pdf Existing space suit designs are essentially a miniature, bubble-boy style space ship. No part of the astronaut is exposed to space. This keeps them safe but also makes it extremely difficult to move your arms and legs. If you’ve seen Neil Armstrong waddling his way across the moon, you can get the idea of how restrictive a fully pressurized space suit is. In fact, the very first space-walk conducted by Russian Cosmonaut Alexei Leonov nearly ended in complete disaster. When he stepped into the vacuum of space, his suit puffed up and stiffened so much that he couldn’t bend his arms to fit back into his capsule. https://en.wikipedia.org/wiki/Extravehicular_activity#First_spacewalk Fortunately Alexi was an Olympic level gymnast and managed to squeeze himself back inside before his air ran out. Astronaut Space Suits have improved a lot since then, which is why we still use them of course. But why not compression suits? Truthfully, we probably have the technology to switch to compression suits today. The original issue that sunk the program was that the suit didn't provide enough reinforcement in certain joint areas such as the armpits. This created a slightly low pressure area and led to the tissue swelling up. With modern advances though finding the right balance of support and flexibility is probably far closer that ever before. Compression suits also have an added advantage that the wearer can breathe a standard mix of oxygen and nitrogen. Current space suits utilize straight oxygen. This has the advantage of providing breathable air at 3.5 psi of pressure, instead of the usual 14 psi you'd find at sea level on Earth. For an astronaut to acclimate his body to 3.5 psi of pure oxygen takes hours. But today space walks are uncommon enough that astronauts can afford to spend hours suiting up and prepping to breath pure oxygen. As people look towards Mars though, no one wants to spend all day prepping for a stroll outside. There have been some attempts are creating hard shelled space suits to hold higher pressures, but who knows. Maybe in ten years someone will dust off a very old idea, and we'll get our awesome futuristic space suits after all.
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You’ve probably heard about the Coriolis Force in relation to your toilet swirling different directions if you live in the northern vs the southern hemisphere.
Ironically, the Coriolis force, while real, is so small that it doesn’t affect your toilet to a noticeable degree. See below. Why the Coriolis Force has Nothing to do With Your Toilet - https://www.smartereveryday.com/toiletswirl But while it may not do much to your toilet, on a ring space-station, which constantly spins to create artificial gravity, the Coriolis Force is a big deal. The impact becomes more noticeable as the space station gets smaller and spins faster. Of course, since Earth is very large and rotates once every 24 hours the force is hard to notice. Medea Station on the other hand is only half a kilometer across and rotates once every thirty seconds. That’s an enormous difference. The Coriolis Force pushes objects to the side when they change elevation in a rotating station. Hence elevators are painted with up and down arrows, and anyone moving up or down stairs experiences a nauseating sensation. But the best part is, the Coriolis Force, despite having very real implications both here and on Earth, isn't real. Confused yet? So what's actually happening on Medea Station? Well to understand the Coriolis Force you have to realize that different parts of the station rotate at different speeds. Now, you may be thinking, no John it doesn’t, if the inside rotated faster than the outside it would tear itself apart. So let’s clarify, the whole station rotates as a single unit, which in physics terms means it all has the same angular velocity. It takes everything on the station the same 30 seconds to make one rotation. But if you take a paper plate and spin it, even though the whole plates rotates as a single unit, you’ll notice the outside edge has a lot further to travel distance wise than a point close to the middle. So, in order for the plate to stay together, the outside edge has to move faster, in speed terms (feet per second), than the inside. Medea Station works the same way. When Devon and Melissa spacewalk their way back to the shuttle bay, they’re right near the center of the Station, the point that everything rotates around. There the station moves at the speed of a slow walk. When they’re standing down in the main station ring though, they’re moving at a blistering 110 miles per hour. If they catch an elevator from the shuttle bay down to the main ring, they have to speed up somehow. Just like you can’t hop into a speeding car from standing still, the Coriolis force pushes to speed them up or slow them down depending on how far they are from the center of the station. It's actually just like if you slam down the gas pedal in your vehicle, depending on how awesome your car is, you'll feel the acceleration shove you back against the seat, pushing your body to accelerate with the car. Now that's what a smooth elevator would feel like, nice, and relaxing. What about if you're climbing a ladder? Well, all that starting and stopping at each rung is like slamming down the accelerator pedal then letting off it, over and over and over and over... you can see why people might get a little dizzy. Lastly, earlier I mentioned that the Coriolis Force wasn't a real force, even though it's effects are very noticeable. What that actually means is that the Coriolis Force is an artifact of being in a rotating reference frame. For an observer standing on Medea Station, the Coriolis Force explains why objects behave the way they do, but if you were motionless outside the station, watching, you could just use normal physics, Force = Mass x Acceleration and come to the same conclusions. Similarly, Earth is a rotating reference frame, and since most people prefer to do physics problems with the ground not moving, they include the Coriolis Force. It's not terribly useful if you're just throwing a ball, but for things like artillery trajectories, or predicting hurricanes, it's a big deal. It might have seemed weird that someone blew a hole in Medea Station and Devon and Melissa weren’t immediately sucked out. But the reality is, unless your right next to the hole, the pressure difference between breathable atmosphere and vacuum won’t suck you out of anything. Certainly, it’s usually nothing like the movie scenes where people are blown out of a space-ship and have to hang on. There are a few rare instances where this could happen but what’s a lot more likely is you hear a rushing noise, feel a breeze then the air is gone and you suffocate in under seconds. I know some of you absolutely don’t believe me at this point, so I’d like to point you to an awesome real world test done by the Mythbusters. They did their test at about 8psi, a little more than half of standard atmospheric pressure, 14.7psi, but it should demonstrate the point.
Mythbusters Test - https://www.youtube.com/watch?v=4yG2h1aDB6k In Devon and Melissa’s case they have a foot or so wide hole in a fairly large room that’s also being fed fresh air from the hallway. Depending on the size of the room they would have about 30 seconds to a minute to escape before they lose consciousness. It’s also worth noting that small pinhole leaks in a ship, can actually be plugged by something as simple as your finger. I don’t suggest trying it or you’ll end up with one very sore, swollen finger, but human skin is a surprisingly good pressure vessel in a pinch. Do space ships launch on a schedule?
In most movies the heroes hop in their spaceship, cruise on up to their space station and that’s it. If you’ve ever watched a SpaceX launch though you’ve noticed they have a countdown. That’s not just to make it more dramatic. That’s because, whatever they're trying to reach is zipping around the planet at tremendous speeds. If SpaceX launches at the wrong time, they'll end up over Australia while the International Space Station is cruising over Europe. IIn which case, Houston, we have a problem. In this specific case if both ships are following the same orbital path, but they're not at the same place at the same time. This is called having an orbit that is out of phase. The way to correct this is by either dropping to a lower orbit, where you move faster and catching up to the target. Or, by going to a higher orbit, ie moving slower, and letting it catch up to you. Both waste valuable fuel, which is why timing with space matters… a lot. |
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