Sign in to follow this  
Acemcbean

What is up with Mars?

Recommended Posts

Seriously, I get there COULD HAVE been life on Mars, which is in-and-of itself a potentialy incredible discovery, but thats not what this is about. What other potential could Mars hold for us? Colonization is most likely not one of the things we could do, as Mars' atmosphere is simply to thin, and it lacks an organized magnetosphere.

Share this post


Link to post
Share on other sites

We could use the name of the planet to name a chocolate bar

MARS_m.jpg

But to be more serious:

I wouldn´t rule out Terraforming ....the gravity of Mars could hold a more dense atmosphere (and has so, in the past) .... so it might be possible to terrform it in a way that it is dense enough an contains enough O2 to be breathable

Share this post


Link to post
Share on other sites

Colonization is exactly the thing we could (and should) do. Venus is too hot and colonizing its upper atmosphere is simply not practical. And the Moon doesn't have an atmosphere at all, thus gets bombarded as heavily as any other place in the solar system with radiation and micro-meteorites. Titan is -175°C and doesn't get a whole lot of sunlight on the surface, it rains methane and water is frozen as solid as rock.

Mars has all the things needed to build a self-sustaining colony. The atmosphere can be made thicker by means of terraforming, which would however take centuries, also would require dragging ammonia-rich asteroids to Mars, or at least the ammonia itself, because Mars doesn't have enough Nitrogen to produce a planet-wide Earth-like atmosphere, and Ammonia is a great and plentiful source thereof. To mitigate radiation, which is about that what astronauts get in Low Earth Orbit, you can bury part of the colony under ground and under things like water tanks. A Magnetosphere is NOT critically needed.

Share this post


Link to post
Share on other sites

The main problem with Mars is the atmosphere. Maybe waiting for a better, more complete analysis of how did martian atmosphere thinned is a better idea ? Magnetosphere is required (if not, thicking the atmosphere is rubbish work - as it have been linked strongly with the loss of it's atmosphere). But a better analysis might make it perfect.

Share this post


Link to post
Share on other sites
And the Moon doesn't have an atmosphere a̶t̶ ̶a̶l̶l̶

It does altough it's negligible.

Share this post


Link to post
Share on other sites

No, a magnetosphere is not required. While you may have to replenish the atmosphere every once in a while, it's not needed to build one in the first place. It took over a billion years for Mars to lose its atmosphere last time.

Share this post


Link to post
Share on other sites

Mars doesn't make a good colony. Why that?

  • The core is cold, so no magnetic field what ever you do.
  • Changing the atmosphere is out of the question. There is no practical way to do that in a reasonal timespan.
  • There is not enough material to produce the needed amount of biomass for plants to enrich the atmosphere with oxygen. So simply throwing algae to change the atmosphere won't work.
  • It is unknown if there's enough water on Mars to support colonization and plant live.
  • Mars is cold, very cold (mean temperature -55°C and it can drop to -133°C!). You'll need to heat it up.
    There are two ways to do that:
    1) Nuclear bombs detonating underground. Millions of them. Won't every happen obviously.
    2) Large mirrors in space heating the planet. Needs millenia to build and move from Earth to Mars.

Next thing: Why do we want to colonize Mars?

  • Ressources? Meh, mining the asteroid field and our moon is easier and cheaper.
  • A place to live? Large regions on our planets are still uninhabited, for example the oceans.

Our Moon is a way better target for colonization. It's "around the corner", there is no annoying atmosphere, and there is He3 - a good fuel for fusion reactors if they ever work.

Share this post


Link to post
Share on other sites

Because it's there.

Mars is close to us and isn't Hell, what more reason do you need to explore it?

Share this post


Link to post
Share on other sites
Mars doesn't make a good colony. Why that?

  • The core is cold, so no magnetic field what ever you do.
  • Changing the atmosphere is out of the question. There is no practical way to do that in a reasonal timespan.
  • There is not enough material to produce the needed amount of biomass for plants to enrich the atmosphere with oxygen. So simply throwing algae to change the atmosphere won't work.
  • It is unknown if there's enough water on Mars to support colonization and plant live.
  • Mars is cold, very cold (mean temperature -55°C and it can drop to -133°C!). You'll need to heat it up.
    There are two ways to do that:
    1) Nuclear bombs detonating underground. Millions of them. Won't every happen obviously.
    2) Large mirrors in space heating the planet. Needs millenia to build and move from Earth to Mars.

Next thing: Why do we want to colonize Mars?

  • Ressources? Meh, mining the asteroid field and our moon is easier and cheaper.
  • A place to live? Large regions on our planets are still uninhabited, for example the oceans.

Our Moon is a way better target for colonization. It's "around the corner", there is no annoying atmosphere, and there is He3 - a good fuel for fusion reactors if they ever work.

  • Mars core isn't cold, and there's plenty of speculation about current volcanic activity on Mars. Though yes - lack of a proper magnetosphere is certainly one of the biggest obstacles in colonizing Mars.
  • Making Mars atmosphere breathable is out of question. HOWEVER we do not need whole atmosphere to be breathable.
  • You are correct, but there is enough material on mars to grow plants as food for humans, possibly also an oxygen for city-size colonies, which is, pretty much all we need.
  • Yes, there is enough water to support colonization and plant life. It's not unknown - it's certain. And it's not only on poles - water ice can be found in numerous places around Mars, though obviously it's much more of it the closer you are to the poles. But again - this assumes that we're not exporting entire China and India to the Mars but rather keep population size reasonable and sustainable (look - complete opposite of what we're doing here on Earth!).
  • You don't need to heat up whole planet. It's enough you can collect solar or wind power to heat up a colony.

  • Mars next to the moon is the easiest location to colonize allowing us to not only mine resources but also refine them sending back to earth high quality products - something that's difficult to achieve by mining asteroids or the moon (moon also got different composition than mars and is far less suitable for sustaining larger mining operations - mostly due to limited supply of water). That however would require a significant effort that very likely will be impossible to achieve any time soon (eg. at a very least you'd need to be able to refuel rockets on a mars that can fly back to Earth - which means production of rocket fuel on another planet - something extremely difficult on it's own)
  • Point of having a place to live is to have a place to live on another planet. In case of a catastrophic event it'd prevent the demise of human kind. Living in oceans doesn't guarantee that. Moon is closer, but moon is also a very risky place to live on - single micrometeorite shower can wipe such colony out of a surface in a seconds. Mars has an atmosphere which is a game-changer.

Edited by Sky_walker

Share this post


Link to post
Share on other sites

We care about Mars so much because it is by far the easiest planet to study. It's close, robots on the surface can work for more than an hour before melting, and you can see the surface from orbit. It's not that we don't care much about the geology of Mercury, the chemical composition of Venus dirt, what's below icy moons' ice or what is consuming hydrogen on the surface of Titan, but it's so much easier, faster and cheaper, to get answers for Mars.

Personally, I'd rather use all Martian exploration funds on icy moons, since they have a better chance of harbouring life right now, even if it means waiting a lot longer between missions that aren't as ambitious as Curiosity.

Mars is great for colonization because it has reasonable temperatures (yeah it's cold, but it's better than Venus or even the Moon), a day-night cycle similar to Earth and a reasonable gravity.

Terraforming it would be very difficult. The nitrogen is not a big problem, we could live pretty well with pure O2 at 02bar, but there is a massive lack of hydrogen, and we'll need a lot of it to get water and biomass. The best option would probably to find some icy asteroids, but that is far beyond hat we can do in the foreseeable future.

Oh, and He3 is rubbish as a fusion fuel (more difficult to fuse than DT, and still not aneutronic), and is super rare in the Moon's crust, so you'd need to process massive amounts of rocks to get a few g of the stuff, it's not sure you could break even. That being said, we'll have permanent settlements on the Moon before we have them on Mars simply because it is easier.

Share this post


Link to post
Share on other sites

Mars lacks the mass to maintain an atmosphere and warm core.

The suns output has increased (warmer temperatures= faster atmosphere loss), and it would lose its atmosphere even faster now that its got no magnetic field, and the outgassing from its mantle has stopped.

For the effort and resources to terraform mars (temporarily, its obvious that it had liquid water in the past, implying an atmospheric pressure and temperatureabove the triple point), we could probably have truly spacefaring civilization - asteroid colonies and such.

Then we could spread to the majority of nearby star systems if we don't need a habitable planet to settle on.

That said... if we were going to terraform a planet... lets look at the list (this is a little like the beginning of War of the Worlds from the 1950s, except not omitting Venus which they still hadn't gotten the public to understand the hellish conditions, and more up to date)

Mercury: LOL, nope

Venus: LOL, nope - some may say it wouldn't be so bad if you thinned out the atmosphere, but it has a severe lack of the element hydrogen (no water), an incredibly long day, and still very intense solar radiation that would cause a runaway greenhouse again in short order if you somehow managed to get it to have oceans of liquid water.

It may have been habitable with oceans 4 billion years ago, but current hellish conditions have erased most evidence and make it too difficult to go look for more subtle evidence.

Earth - home sweet home, lets not f*** it up

-Earth's moon: LOL, nope, not enough gravity to hold on to an atmosphere, to easily wiped out by the same sort of calamity that may affect Earth.

Mars - probably not worth the effort, but closest so far: in the Hellas basin the atmosphere gets just thick enough to allow liquid water to exist (temporarily, in theory). The day is similar, it has enough gravity to hold on to a breathable atmosphere for a limited amount of time (a millenia or two perhaps much more). Current temperatures sometimes get into the comfortable range (but with such a thin atmosphere, the temperature swings can be pretty wide, from a veyr warm 35C, to -120 C).

Clouds of water ice on occassion, the Phoenix lander appears to have imaged a salty brine on its landing legs (liquid salt water perhaps). It contains clear signs of being habitable once.

Jupiter: LOL, nope

- Its moons: LOL, nope to terraforming, none could hold an atmosphere, nor would they receive enough light, nor is the surface radiation anywhere close to healthy... underground colonies may be feasible on Europa/Ganymede/Callisto.

Saturn: LOL, Nope

- Its moons: LOL, nope to terraforming, none could hold an atmosphere at 25C, nor would they receive enough light, nor is the surface radiation healthy... underground colonies may be feasible. Titan would be interesting, as the atmospheric pressure is survivable (though the temperature is not). Its mainly nitrogen, so it wouldn't be too toxic to breath if you warmed it up and had supplemental oxygen, so surface colonies may be feasible, and if there is a hole, it wouldn't be as bad as a hole in a colony exposed to a vacuum...

Uranus: LOL nope

-Its moons: underground colonies may be feasible (but these would be little different than asteroid colonies)

Neptune: See above.

Share this post


Link to post
Share on other sites

tl;dr: Everything except Earth and Mars: LOL, nope.

Mars could probably hold an atmosphere for millions of years, maybe even long enough for Mars to become uninhabitable due to the Sun's circumstellar habitable zone shifting beyond Mars. Mars also seems to have endured some pretty bad impacts, which could also have played a major part in the loss of its atmosphere.

Share this post


Link to post
Share on other sites
We could use the name of the planet to name a chocolate bar

http://www.westoneswholesale.com/WebRoot/BT2/Shops/BT3918/4BA1/F984/2535/937F/DE68/0A0A/33E7/B56F/MARS_m.jpg

But to be more serious:

I wouldn´t rule out Terraforming ....the gravity of Mars could hold a more dense atmosphere (and has so, in the past) .... so it might be possible to terrform it in a way that it is dense enough an contains enough O2 to be breathable

i believe that the mars bar is named after a person, not a planet.

Share this post


Link to post
Share on other sites

We can't, at this point, live on Mars (or any other planet) without a supply chain. Since launch windows are every 2 years, maintaining a supply chain is pretty much beyond our capabilities. Infrequent windows mean that you need to compensate with large payloads, which means that you need big expensive rockets, with a heavy infrastructure that is going to cost a lot to maintain for such infrequent launches.

There is no point in building a colony if there is no trade, commerce, or logistics chain between the "colony" and the "homeland". We might be able to build a logistics infrastructure between the Earth and the Moon one day, but sustainable regular transit to Mars is going to be extremely hard and expensive for a long while. It's simply not gonna happen soon. Deal with it.

The reason why there is scientific interest in Mars is because it's the only other planet that is actually within a reasonable distance and accessible with our technology. Studying the physical and chemical phenomena that occur there gives us more data points and allows us to extrapolate results to broaden our knowledge on a fundamental scale and also applied to our own environment.

Share this post


Link to post
Share on other sites
We can't, at this point, live on Mars (or any other planet) without a supply chain. Since launch windows are every 2 years, maintaining a supply chain is pretty much beyond our capabilities. Infrequent windows mean that you need to compensate with large payloads, which means that you need big expensive rockets, with a heavy infrastructure that is going to cost a lot to maintain for such infrequent launches.

Nothing says you can't launch multiple rockets in the same launch window.... so you don't need big expensive rockets, you could get away with many cheap rockets, that are cumulatively expensive.

Mars colonization probably won't happen, but its still a far more interesting and accessible planet than any others (though jupiter and saturn have quite a few interesting bodies in orbit around them, the planets themselves are pretty inaccessible -> descend through clouds into the abyss - > end of mission)

Share this post


Link to post
Share on other sites
Mars lacks the mass to maintain an atmosphere and warm core.

The suns output has increased (warmer temperatures= faster atmosphere loss), and it would lose its atmosphere even faster now that its got no magnetic field, and the outgassing from its mantle has stopped.

For the effort and resources to terraform mars (temporarily, its obvious that it had liquid water in the past, implying an atmospheric pressure and temperatureabove the triple point), we could probably have truly spacefaring civilization - asteroid colonies and such.

Then we could spread to the majority of nearby star systems if we don't need a habitable planet to settle on.

I don't believe that's the case. Mars has enough gravity to prevent large scale thermal escape of a CO2, or even nitrogen, atmosphere, It's more than twice as far from the sun as venus, and solar radiation scales with the square of distance, so Mars only gets about 20% of the solar radiation Venus does, with 40% of the surface gravity. Venus also doesn't have a magnetic field, and is far hotter, so if Venus can hold an atmosphere for billions of years, then maybe so can Mars. We don't really know why Mars lost its atmosphere, so I don't think we can say it could never keep one.

Share this post


Link to post
Share on other sites

I have two issues with what's been said:

Exploring the solar system for traces of life is a waste of time and resources, there is no life besides us here, and there never was. Basic statistics can prove this.

Terraforming a planet is far beyond our technology, not to mention is it wasteful and foolish. Planets are inherently problematic because of their gravity wells as well as sheer scale. Space based colonization is a far better alternative.

Share this post


Link to post
Share on other sites
I have two issues with what's been said:

Exploring the solar system for traces of life is a waste of time and resources, there is no life besides us here, and there never was. Basic statistics can prove this.

I have a hard time believing this. What basic statistics conclusively prove there is nothing beneath the surface of Enceladus or Europa? Or that there was nothing living on Mars 2 billion years in the past? Maybe there is nothing out there, but basic statistics, or basic anything isn't going to prove it one way or the other.

Share this post


Link to post
Share on other sites
I have two issues with what's been said:

Exploring the solar system for traces of life is a waste of time and resources, there is no life besides us here, and there never was. Basic statistics can prove this.

We have a sample base of exactly 1. That's not enough to extrapolate any meaningful statistics.

Note that most science payloads on our probes are designed for studying chemical and geological properties. The "search for life" is mostly a media thing to get the public interested that doesn't reflect the actual science that's being done.

Share this post


Link to post
Share on other sites

Pure CO2 is not a terraformed atmosphere.

Escape valocity for mars is 5.03 km/sec

That is less than half that of Earth's 11.18 km/sec

Which means the KE of the gas molecules before they start to reach escape velocity at a high rate can only be must be 1/4th of that of Earth.

Its orbit is at about 1.5 AU, meaning it gets just under half the sunlight of Earh....

Half the energy input, but the gas needs 1/4 the energy to prevent escape.

Also note that CO2 has a much higher MW than N2 -> 44 vs 28

Its also much higher than that of H2O -> 18

The average velocity of the speed of the gas molecules will be: http://en.wikipedia.org/wiki/Root-mean-square_speed

Of course, that is the average, and the closer that is to the escape velocity, the more you will have that actualy acheive escape velocity.

Lighter gas molecules are more easily lost.

You bring up Venus, with its atmosphere of heavy CO2 with a MW of 44, which almost completely lacks water vapor.

Its atmosphere is severely deficient in hydrogen containing compounds.

Note that a thick atmosphere can help retain lighter gases, much like volatile compounds will evaporate slower when they are in a solution.

Any N2 that reaches escape velocity will likely impact another gas molecule before escaping, and slow down again. As nitrogen is only ~3.5% of the atmosphere, its rate of loss is much slower than it would be if the CO2 wasn't there.

Earth's mainly nitrogen, argon, oxygen, and H2O atmosphere wouldn't last long on Venus, and it wouldn't last long at Mars, particularly if you warmed mars up to Earthlike temperatures. (Athough, with massive mirrors blocking the sun on Venus, and a magnetic field to help retain the hydrogen that is produced by the suns rays splitting water, venus could hold on to an earth like atmosphere, but again with oceans, and without blocking much of the sun, it would again have a runaway greenhouse)

High CO2 concentrations to warm it and reduce the loss of other gasses would render the atmosphere unbreathable, long term exposure to CO2 above about 5% begins to be toxic to humans.

Warm temperatures with relatively light gasses requires a pretty large escape velocity.

Titan retains N2 because its so cold... that gas would all escape if it was warmed up to something like 10C.

Mars wouldn't lose its atmosphere as fast, but it would.

The lack of a magnetic field would cause it to lose hydrogen faster.

Share this post


Link to post
Share on other sites
I have a hard time believing this. What basic statistics conclusively prove there is nothing beneath the surface of Enceladus or Europa? Or that there was nothing living on Mars 2 billion years in the past? Maybe there is nothing out there, but basic statistics, or basic anything isn't going to prove it one way or the other.

See this: http://en.wikipedia.org/wiki/Drake_equation

Based on our current experience (finding nothing) and understanding of processes required, the statistical probability of life occurring twice in the same solar system is amazingly small, and if you factor in estimates from the Drake equation (even if you take a very high estimate) life is still amazingly rare in our universe.

As such I can easily justify my statement that "Exploring the solar system for traces of life is a waste of time and resources" It would be much better to direct those resources towards expansion and progress instead of wasting them on looking for something that isn't there.

EDIT:

We have a sample base of exactly 1. That's not enough to extrapolate any meaningful statistics.

Note that most science payloads on our probes are designed for studying chemical and geological properties. The "search for life" is mostly a media thing to get the public interested that doesn't reflect the actual science that's being done.

That's not true, we have a number of samples of "no, nothing here"

To what end? Any science being done is inherently tied to the "search for life"

Edited by Xaiier

Share this post


Link to post
Share on other sites

That's not true, we have a number of samples of "no, nothing here"

We have a handful of samples of "we don't know". Still not enough to make any meaningful statistics.

To what end? Any science being done is inherently tied to the "search for life"

Rubbish. How many space exploration probes carry instruments whose purpose is to actually "detect life"? At best some are designed to detect some tell-tale molecules, but the main science payloads are to study geological and chemical processes that have nothing to do with the search for extra-terrestrial life.

Share this post


Link to post
Share on other sites
Pure CO2 is not a terraformed atmosphere.

Escape valocity for mars is 5.03 km/sec

That is less than half that of Earth's 11.18 km/sec

Which means the KE of the gas molecules before they start to reach escape velocity at a high rate can only be must be 1/4th of that of Earth.

Its orbit is at about 1.5 AU, meaning it gets just under half the sunlight of Earh....

Half the energy input, but the gas needs 1/4 the energy to prevent escape.

Also note that CO2 has a much higher MW than N2 -> 44 vs 28

Its also much higher than that of H2O -> 18

The average velocity of the speed of the gas molecules will be: http://en.wikipedia.org/wiki/Root-mean-square_speed

Of course, that is the average, and the closer that is to the escape velocity, the more you will have that actualy acheive escape velocity.

Lighter gas molecules are more easily lost.

You bring up Venus, with its atmosphere of heavy CO2 with a MW of 44, which almost completely lacks water vapor.

Its atmosphere is severely deficient in hydrogen containing compounds.

Note that a thick atmosphere can help retain lighter gases, much like volatile compounds will evaporate slower when they are in a solution.

Any N2 that reaches escape velocity will likely impact another gas molecule before escaping, and slow down again. As nitrogen is only ~3.5% of the atmosphere, its rate of loss is much slower than it would be if the CO2 wasn't there.

Earth's mainly nitrogen, argon, oxygen, and H2O atmosphere wouldn't last long on Venus, and it wouldn't last long at Mars, particularly if you warmed mars up to Earthlike temperatures. (Athough, with massive mirrors blocking the sun on Venus, and a magnetic field to help retain the hydrogen that is produced by the suns rays splitting water, venus could hold on to an earth like atmosphere, but again with oceans, and without blocking much of the sun, it would again have a runaway greenhouse)

High CO2 concentrations to warm it and reduce the loss of other gasses would render the atmosphere unbreathable, long term exposure to CO2 above about 5% begins to be toxic to humans.

Warm temperatures with relatively light gasses requires a pretty large escape velocity.

Titan retains N2 because its so cold... that gas would all escape if it was warmed up to something like 10C.

Mars wouldn't lose its atmosphere as fast, but it would.

The lack of a magnetic field would cause it to lose hydrogen faster.

I looked into this before, and the best analysis of loss by thermal diffusion I've found is reproduced in this post: http://forum.kerbalspaceprogram.com/threads/70211-Terraforming-Mars?p=988493&viewfull=1#post988493

And also this one: http://forum.kerbalspaceprogram.com/threads/70211-Terraforming-Mars?p=992740&viewfull=1#post992740 .

The maths suggests that Mars should be able to hold onto a thick atmosphere of nitrogen for a timescale of billions of years, although it will lose water vapour over this time. Why it doesn't isn't currently known, but we can't yet say with certainty that Mars is incapable of holding onto a thicker atmosphere.

Share this post


Link to post
Share on other sites

If nothing else having nitrogen or argon or some other buffer gas atmosphere would help protect colonies even if they have to be sealed so they can be breathable due to 'oh hey meteors' and allow for temperature regulation.

Don't get me wrong, having rain and a water cycle and stuff would be great. However I'd settle for 'puncture in dome isn't going to cause air to rush out.'

Would it be hard? Yes. However I consider it worth going to. There's enough minerals there that should allow it to be self sufficient. We just need to get the sort of funding the military has.

Share this post


Link to post
Share on other sites
This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this