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How far would you go to stay “in sim”?

The goal of this exercise is to live and work in a simulated Mars environment. But obviously we aren’t actually on Mars, and it is physically possible to go outside and breathe the atmosphere here (although it has been so cold that actually surviving the night outside the Hab would be challenging!). So during the mission, we distinguish between things done “in sim” (imposing constraints as if the outside environment were Mars) and “out of sim” (reverting to actual Earth constraints).

As you’d expect, we strive to do everything possible in sim. The day a new crew arrives is an exception, since there are 12 people (but only 6 suits) and a lot of information has to be conveyed in a short time, walking around to see and learn all of the systems. But after that, we are confined to our Hab, or going out in suits, aside from our “pressurized tunnels” that connects the Hab to the GreenHab (water recycling), “pressurized garage” where the ATVs live, the Musk Observatory, and the Engineering Station where the generators and fuel supplies are. These aren’t enclosed, but we pretend they are, since in a real landed mission the crew would likely have erected just such connections so that they could access those critical systems not actually in the Hab. The tunnels are delineated with rock-lined paths, so we are careful not to step outside of them.

But of course, staying in sim has its tedious downsides (that’s part of what you learn from this experience), like when you’re in your spacesuit and you get halfway through the 5-minute wait to “depressurize” the airlock, then remember that you forgot to grab the ATV keys. You could “break sim” to reach back inside and get the keys, or stay in sim and wait to repressurize the airlock, go inside, get the keys, return to the airlock, and wait to depressurize again. In this case, we opted to have another crew member run the keys outside (through the pressurized tunnel, to the pressurized ATV garage) and put them in the ATVs—since on Mars, we wouldn’t bother to bring the keys in and out with us. (It is incredibly remote here, but in theory it is possible for other people to wander down the road to the Hab and therefore the ATVs could be stolen, if we left the keys in them all the time.) But each such snag has to be worked through logically, to determine what would or would not be possible in a Martian environment, so that we can keep the simulation fidelity as high as possible.

So far we have opted in every such case, but one, to stay in sim, including two days ago when an EVA crew had to come back in and go through the pressurization/depressurization cycle to retrieve sunglasses (the snow was too bright!). As a result, EVA 7 became EVAs 7 and 8, and of course, this took up more time than planned.

The one exception to staying in sim was on EVA 8, when Carla’s helmet fogged up so much that she could not see where she was walking! After trying a variety of methods to deal with the condensation, she finally gave up and took off her helmet. In a real mission, she would probably have put her arm on another crew member’s shoulder and followed them, blind, back to the Hab. We had a good time joking about “dead” Carla, and considered holding a memorial session for her that night, but she declined. 🙂 Meanwhile, Brian’s helmet was just as fogged, but he was too darn stubborn to take it off!

This experience also got us thinking about other good exercises to conduct on EVA. What if a crew member were physically incapacitated and could not get back to the Hab under their own power, even being led? Previous crews have experimented with a fireman’s carry. We’ve decided to try a strategy based on our current weather conditions (3 inches of snow on the ground). I can hear some of the crew outside sawing and assembling a sled. We plan to have one EVA crew go out, get far enough to be out of line of sight, and then have a simulated accident in which one crew member cannot move. At that point they’ll radio back their GPS coordinates, and we’ll send a second crew out on the ATVs, with the sled, to rescue them. We’ll report back on this ambitious plan and what we learn from the attempt!


  1. Wendy says:

    I love this post, because it’s been the root of most of my questions!

    When you were describing the need for keys in the airlock, it made me realize that a real Mars expedition might benefit from a ‘pass-through’ in the airlock. I’m visualizing a little mini-airlock that doesn’t need a slow de-pressurization method, to be used for small objects. You could put something in from the hab, ‘pop’ the pressure to wherever the airlock is in it’s cycle, and then the folks in the airlock could grab the keys, sunglasses, etc. Of course, on Mars you’d probably have tons of checklists for all circumstances, but you also wouldn’t be able to predict many situations, since it would all be brand new.

    Another possible solution that’s reasonable for Mars but less-so for human-filled Earth is an outside store of equipment, as you described with the keys. For example you could fill it with ropes, rock hammers, extra bottles of air, tools to fix the ATV and other things useful outside the suits. That way you’d only have to return to the hab for things you needed inside the suits, like the sunglasses. (And of course, your helmets would probably have light-sensitive shading built in like fancy glasses, since hopefully you’d be super-well-funded for this trip!)

    I like the descriptions of the ‘tunnels’ used to do engineering tasks outside the Hab. In a real Mars environment, would they be pressurized, but not heated? Would you need to go through an airlock, or wear cold-weather protective gear to enter exit? I’m also curious how well a crew would do without access to these pseudo-tunnels, in terms of feeling claustrophobic or confined? It seems like even after just a few days all of you are jumping at a chance to go outside, and a Mars crew would be there for much longer and with less freedoms. How would you rate your ‘cabin fever’ at this point? I’m curious about Brian’s experience in a longer sim as well, was confinement the biggest obstacle?

    Do you guys get any rest days while you’re there? The non-stop work seems exciting and interesting, but also draining after a while.

    I hope you’re all having fun! Thanks for including mundane things like meals and snowmen in your updates, it’s really great reading along with you!


  2. Crew 89 Biologist says:

    Hi Wendy,

    Thanks for your continuous interest in our mission. Those are some good points indeed.

    Ideally the pressurized tunnels would be at room temp, however I think that in practice they would be around freezing temp just to save energy.

    It is funny that you ask about the ‘cabin fever’ because a couple of days ago Carla was feeling that she should go on an EVA since she was locked for a couple of days at the hab doing other stuff. Now I have not been on an EVA for a couple of days and although I have been hyper busy at the hab, I start feeling I should go out. Actually, I am planning an EVA for tomorrow.

    All the other 5 members of the crew are out simulating the rescue mission and I am ‘habcom’….someone had to stay in [and I am a bit sick so I volunteered] 🙂 But I am very very jealous of them since the skies are clearing and the view is magnificent.

    Hopefully we will have a good look of Mars and the Moon later on today/night

  3. Kiri says:

    I love the idea of a small airlock pass-through! And the outside stash of equipment, too. And actually, even at MDRS we literally have “tons of checklists” (almost more than we can keep track of, but we’re getting better as we establish routines).

    My cabin fever hasn’t been too bad so far. But partly that is due to the “pressurized” tunnels — they do afford a bit of fresh air and a view! Interestingly, though, we’ve found that as we get more used to “sim”, our view narrows when we’re in the tunnels — you stop looking outside of them, because you mentally think of them as having walls. Kind of funny.

    Gosh, a rest day is a wonderful idea! For me, I think, the pace is a bigger challenge than cabin fever — constantly being “on” and responding to activity coming from five directions takes a lot out of me.

    And thanks in general for reading along and contributing all of your great comments 🙂 Three of the guys already have crushes on you!

  4. Wendy,

    Thanks for your thoughtful comments. They are very good suggestions. The mini airlock idea is interesting. Are you aware of any analogous systems like it? An outside tool shed makes perfect sense. In a real base, tools would be assessable in the pressurized garage and in toolcases attached to the rovers. An outside cabinet is a good idea too, but I wonder what the thermal effects on the tools would be. Maybe they would be too brittle after the prolonged exposure to the cold.

    On the FMARS expedition, cabin fever wasn’t a huge factor since we were going outside often enough that the feeling of confinement didn’t overwhelm us. In some ways, the simulation here at MDRS is more realistic because we don’t have to break sim to refuel the generator 3 times a day, collect our own water from a stream a few km away, and haul away greywater daily. However, I being isolated for so long with only 5 other people can be challenging. Check out the FMARS 2007 mission for more on what a 4-month simulated Mars mission was like.

    The days go fast here, and we always have a surplus of tasks an a deficit of time. The pressure to get daily reports and photos submitted on time can be a stressor. It takes concerted effort to carve out time for recreation, exercise, or anything else not considered mission critical. I don’t think marsnauts will get bored, but they do run the risk of overworking themselves. On a 2-week mission like ours we can sustain this fast pace, but long missions should have slower paces.

    On to Mars!

  5. Paul Graham says:

    It’s funny how crews have the same problems over and over again. That was one of my great disappointments. We never could get crews to read or update the documentation. nor could we implement the wiki concept properly for such crew added docs.

    First off, in the real world, the “Mini-rovers” wouldn’t have keys. (Who’s going to steal them on Mars?) so, a mistake like that is out of sim to start with, finding the keys magically in the ‘lock would be a reasonable repair to sim. Secondly, there was a “sample lock” planned, but we never could get the funding to actually build it. The procedure however, is simply to have whoever in the hab toss the keys in the lock, and since there is no one in the lock, you can pump it down much faster, (and you can pressurize it pretty much instantly. You can’t do that with someone in the lock.) and you would have your keys (or camera as it happened to the crew that we developed this plan for.) by the time you walked back to the lock.

    A few other thoughts from this. Their is not supposed to be a tunnel to Engineering, because “The James Montgomery “Jimmy” Doohan Memorial Engineering and Service Support” or “Main Engineering” is by definition out of sim. There will be no generators or LP or (I guess you aren’t using the water tank anymore – Pity) any of that in a real mission, and you certainly won’t be walking over to the nuke. So, The whole idea of walking out there is out of sim, no tunnel needed. The same applies to the Musk Observatory. It the real world, any such observatory would be robotic, you wouldn’t actually go into it for observations. (As this observatory was set up for the last time I saw it, but we would often go in it because it is a lot more fun, and required human intervention to open it up.)

    As far as the RAH Memorial Tunnel (to the greenhab,) although it probably wouldn’t be heated, the buildings on either side are, and would probably stay relatively warm. (about freezing in the real world.) but who cares? you would only be in it for a few seconds, and Humans are remarkably resilient to such things.

    We had a trailer for rescued crew members and ATVs. (and one person can load up both.) Not sure what happened to that.

    As far as teh getting into sim – Oh yes it happens, you do very quickly get used to the idea, and freak out (a little) when something out of sim happens, and you do get quickly into the feeling that their is death “out there”.

    The cabin fever? Yup, that’s part of it too. I hated being stuck in the hab for days at a time.

    Whoever your HSO is mail me in private, and I’ll tell you how to do real fire drills, and top fidelity sim ones as well… (Ask any one who’s ever been part of one of my fire drills…)

    Good luck!


  6. Wendy says:

    Wow, so many cool ideas! Paul, what a simple solution for passing non-living things through the lock, it’s logical but it never occurred to me either.

    I wonder about the comments regarding the reality of the ‘tunnels.’ If those specific devices won’t be used, is it unrealistic to think that there’d be other equivalent devices that need daily checks and/or maintenance to run the hab? I realize of course that such a thing would be much, much higher budget. But for example, if the Hab were to be powered by solar energy (wouldn’t that be cool!) then wouldn’t the panels almost certainly need a frequent check and dusting to keep them at their optimal output? If it were powered by something more sophisticated, (Paul, were you serious about nuclear?) then surely that wouldn’t be located in the hab, since heated, oxygenated, pressurized space is at a premium? I’m sure you guys have thought about this much much more than I have, but it seems like there’d probably be all sorts of equivalents to the system available now.

    It makes sense to me that the tunnels would be colder, so you’d need coats if you were spending more than a few minutes in them. I started thinking about it in terms of the claustrophobia of rarely getting out of the hab, and then only in the EVA suits. However, now I’m intrigued by the engineering challenges as well. For example, such tunnels would be basically the same construction as the hab, just with no heating, or they’d be significantly less structurally sound just due to the need to carry less construction materials. In that case, wouldn’t you need to wear suits even in the tunnels, in the possible case that they ruptured? Perhaps a suit with no air tank in operation, but with the ability to immediately turn it on in an emergency? Of course, there’s so much speculation here that I probably need to study a whole bunch of existing information before I start asking these kind of details. But it’s really fascinating to start thinking it through.

    I was thinking about the sled building, and figured it was probably because a wheeled trailer wouldn’t work well in snow. Of course, that makes you wonder about the reality aspects, since there’s no snow on Mars, but perhaps there are situations where a wheeled vehicle is not practical, and you’d need something more like a sled, travois or at least some sort of EMT backboard to extract an injured crew member?

    Ok, I’m running into more questions now, so I’m going to look into Brian’s FMARS info, because I’m sure I’ll learn an awful lot there.

    Thanks again everyone for taking so much time to answer all my questions and bring this to life. This is almost like living there with you!

  7. Paul Graham says:

    Hi Wendy, Well, as you probably don’t know, I was the Mars Societies Engineering Team Coordinator for a great many years, and have spent a great deal of time on both habs, and even more time working up the right ways to do things. (I have since left that post, but not MS to be involved in a real Lunar exploration mission, )

    As far as the tunnel question, Well, yes, I was serious about the nukes, and if you were using solar panels, you’d have to clean them off in a suit…

    As far as the tunnels, Wearing a suit in there would be clumsy, and with the trivial odds that you would have an accident large enough to catastrophically damage the tunnel without killing you instantly is low enough as to not be concerned with. The (inflatable) tunnel could tolerate light damage and give you plenty of time to get to safety.

    If the area is clear enough to get an ATV back there, it’s clear enough to get a trailer back there.

    E-mail me if you ‘d like more info.


  8. admin says:

    Great conversation!

    As it turns out, Wendy, it does snow on Mars — but mainly near the polar regions, and often it doesn’t reach the surface (as with rain). The Phoenix lander reported observing snow (indirectly) far above it, which never reached the ground. When it gets cold enough, in the polar regions, it can “snow” frozen CO2.

    I love all of your comments and questions — and thanks to Paul for his responses based on his experience! My assumption is that anything critical to the crew’s survival which might need regular monitoring would need to have some sort of pressurized connection to provide easy (and fast) access. It might well not be heated, but it should have enough pressure to be survivable. In that respect, our “tunnels” are pretty realistic; they’re not at all heated, but with lots of layers/coats we can certainly dash between stations. Of course, ideally any support portions of the landed complex would be able to be monitored and controlled from afar (e.g., inside the warm and pressurized Hab). But things do break, and suiting up to fix or clean or check them would be not just tedious but in some cases a real obstacle to avoiding costly repairs or even threats to the crew’s existence (e.g., water or fuel tank leaks or a million other disaster scenarios you’ve probably already thought of).

    Also, Paul, I passed on your comment to our HSO… we may be in touch about fire drills. 🙂 Thanks!

  9. admin says:

    Oops, meant to post that as Kiri. 🙂

  10. Paul Graham says:

    Thank you Kiri.
    As another point of knowing what has happened, You might take a look at Hugh Gregory’s Project Mast. He has photographically documented the entire MDRS operating theater… (Cost him a fortune and a couple months.) You may find that useful in your location program.

    You might also enjoy the suits I am developing for OpenLuna. – the primary design interest here is that you could put it on in just minutes.