In my last post, I mentioned an emergency EVA. An EVA (extra-vehicular activity) is our only direct interaction with the outdoors. On sMars we have to assume that the atmosphere outside our habitat will not provide us with breathable air. We also assume that the dust and soil outdoors could be harmful to our health. To protect ourselves, we wear simulation space suits at all time when outside the habitat. The land that we traverse is rocky, sharp and unstable preventing a challenge when trying to cross it on foot. We don’t have a rover or vehicle on sMars, so all EVAs are done on foot under our own power.
When prepping for an EVA, we have to consider how to access all the equipment and information we will need. Like any hike, we want to have plenty of water, snacks and a map of where we plan to go. We also need specialized equipment, like GPS devises, recording equipment and radios. The suits are sealed before we exit the airlock, so anything you need to access must be sealed inside the suit with you or be carried/tied to you on the outside your suit . When performing the emergency EVA to turn on the backup generator, I brought our habitat manuals for reference. I couldn’t fit these inside the suit with me, so I had to carry them out in my hands. This isn’t the best option, because you have to set it down or fumble with full hands. For quick reference, I taped a circuit diagram inside my suit to the bottom of my visor — no way to drop it or let it blow away then and I could refer to it while I worked with my hands.
The suits are cumbersome to simulate the difficulty maneuvering and communicating in a pressurized space suit. You don’t have much dexterity in your hands and every step is shorter and less stable with folds of material around your joints blocking mobility. Your visor fogs, your suit often gets overheated and you have to turn your whole body in order to see things you’d normally view in your peripheral vision. You can’t hear anything beyond your fans, your boots crunching over the lava and if you’re lucky, you can hear the radio. It’s easy to lose track of your partner if you don’t turn around and visually check for them.
But despite (or because) of all that, the EVAs are a great way to learn about ourselves and the planet we live on. We test our mettle even while we test our soil. Our only way to collect geology information directly is to collect data out on EVA, and getting out of the habitat a few times a week is a boost to crew morale. With just a half dozen EVAs under our belts, we’ve greatly improved how we walk, communicate and gather data. Already, it’s easier to scramble up a hill or keep our balance over tricky a’a lava flows. And it’s just good fun!