First, night time temperatures on Mars get below the freezing temperature of dry ice even in equatorial regions, for many days of the year. So, no way could you survive those levels of cold without a lot of thermal protection.
In the daytime it occasionally gets as hot as 20C in summer in full sunlight - so the temperatures would be okay, briefly for a few hours on the warmest days, for humans in midday summer sunlight in the "tropical" areas of Mars.
But apart from that, the Mars atmosphere is a near vacuum, well below the "Armstrong limit" where you can survive without a pressurized spacesuit.
If you just have oxygen to breathe and protection from cold, you'd die very quickly because your saliva and the moisture lining your lungs would boil, because they are well above boiling point in such thin air (just as the boiling point of water goes up in a pressure cooker, it also goes down when the pressure is low, for instance at the top of Mount Everest, and even more so in a near vacuum like Mars).
So, without a spacesuit, you'd get frostbite at night or in shadow, you wouldn't be able to breathe, and the moisture lining your lungs and mouth would boil.
With a spacesuit, you could survive on Mars. But our spacesuits are complicated multi-million dollar machines, that take months to build by hand, they are like a mini spacecraft. All of that has to work right, they aren't the simple easy to put on and robust machines of science fiction - not yet anyway. And - they could be damaged. An accident, relatively minor - one that might end up with, a bruise or a cut, a twisted ankle, or at worst, broken bones perhaps - would risk damaging your spacesuit, and that would probably kill you on Mars.
And you'd always have to keep in mind your oxygen levels as it is unlikely that your spacesuit could be a closed system or have days worth of oxygen in it. So you'd have to keep track of how long it takes you to get back to a supply of oxygen and make sure you never stray further away than a distance you could travel back quickly in case of an accident or issue of some sort or other arising.
Again, an accident that leaves you unable to walk at a normal pace, on Earth would be a minor nuisance, but on Mars would probably mean you can't get back to your oxygen in time and you'd die. Of course, you'd have a buddy system, where you always go everywhere at least in twos, and work around it in other ways, but this is another thing that makes it less safe and requiring more care. Even with a buddy, if you have a sprained ankle or some such, it might slow them down, the need to carry you or support you, enough so that you both die because you can't reach oxygen in time, so you'd have to factor that in as well.
And with present day spacesuits anyway, it takes some time to get your spacesuit on, not just minutes, of order an hour or two. And many precautions to take and things to check for safety.
I think, arguably, you'd get a much better experience of what it is like to walk on the Mars surface from orbit using telepresence, and it is also far safer as you operate it from inside your spaceship in a shirt sleeves environment.
That way you can operate a telerobotic "avatar" on the surface which doesn't need a spacesuit, can have digitally enhanced vision, and haptic feedback so you can actually feel what you touch. And the arms, fingers etc would be much more flexible than they are in a spacesuit. And as it doesn't need oxygen, you can just leave it standing still while you go away for coffee or have a sleep. Or more likely, leave it doing some routine tasks, while you operate another rover or are sleeping or taking a break.
It's probably not going to be as efficient as a human without a spacesuit on the surface - but that's not comparing like with like. Compared to humans on the surface with a spacesuit, it might be as efficient, and certainly far easier and safer, also lower cost.
And this shows the amazing views you'd get in the HERRO orbit, another way of exploring Mars from orbit.
It may also be required to keep humans in orbit, especially if we find habitats for Earth life on Mars, for reasons of planetary protection.
See my To Explore Mars With Likes Of Occulus Rift & Virtuix Omni - From Mars Capture Orbit, Phobos Or Deimos
In the daytime it occasionally gets as hot as 20C in summer in full sunlight - so the temperatures would be okay, briefly for a few hours on the warmest days, for humans in midday summer sunlight in the "tropical" areas of Mars.
But apart from that, the Mars atmosphere is a near vacuum, well below the "Armstrong limit" where you can survive without a pressurized spacesuit.
If you just have oxygen to breathe and protection from cold, you'd die very quickly because your saliva and the moisture lining your lungs would boil, because they are well above boiling point in such thin air (just as the boiling point of water goes up in a pressure cooker, it also goes down when the pressure is low, for instance at the top of Mount Everest, and even more so in a near vacuum like Mars).
So, without a spacesuit, you'd get frostbite at night or in shadow, you wouldn't be able to breathe, and the moisture lining your lungs and mouth would boil.
With a spacesuit, you could survive on Mars. But our spacesuits are complicated multi-million dollar machines, that take months to build by hand, they are like a mini spacecraft. All of that has to work right, they aren't the simple easy to put on and robust machines of science fiction - not yet anyway. And - they could be damaged. An accident, relatively minor - one that might end up with, a bruise or a cut, a twisted ankle, or at worst, broken bones perhaps - would risk damaging your spacesuit, and that would probably kill you on Mars.
And you'd always have to keep in mind your oxygen levels as it is unlikely that your spacesuit could be a closed system or have days worth of oxygen in it. So you'd have to keep track of how long it takes you to get back to a supply of oxygen and make sure you never stray further away than a distance you could travel back quickly in case of an accident or issue of some sort or other arising.
Again, an accident that leaves you unable to walk at a normal pace, on Earth would be a minor nuisance, but on Mars would probably mean you can't get back to your oxygen in time and you'd die. Of course, you'd have a buddy system, where you always go everywhere at least in twos, and work around it in other ways, but this is another thing that makes it less safe and requiring more care. Even with a buddy, if you have a sprained ankle or some such, it might slow them down, the need to carry you or support you, enough so that you both die because you can't reach oxygen in time, so you'd have to factor that in as well.
And with present day spacesuits anyway, it takes some time to get your spacesuit on, not just minutes, of order an hour or two. And many precautions to take and things to check for safety.
I think, arguably, you'd get a much better experience of what it is like to walk on the Mars surface from orbit using telepresence, and it is also far safer as you operate it from inside your spaceship in a shirt sleeves environment.
That way you can operate a telerobotic "avatar" on the surface which doesn't need a spacesuit, can have digitally enhanced vision, and haptic feedback so you can actually feel what you touch. And the arms, fingers etc would be much more flexible than they are in a spacesuit. And as it doesn't need oxygen, you can just leave it standing still while you go away for coffee or have a sleep. Or more likely, leave it doing some routine tasks, while you operate another rover or are sleeping or taking a break.
It's probably not going to be as efficient as a human without a spacesuit on the surface - but that's not comparing like with like. Compared to humans on the surface with a spacesuit, it might be as efficient, and certainly far easier and safer, also lower cost.
This is the spectacular view of Mars from Deimos
And this shows the amazing views you'd get in the HERRO orbit, another way of exploring Mars from orbit.
It may also be required to keep humans in orbit, especially if we find habitats for Earth life on Mars, for reasons of planetary protection.
See my To Explore Mars With Likes Of Occulus Rift & Virtuix Omni - From Mars Capture Orbit, Phobos Or Deimos
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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