This is the
talk page for discussing improvements to the
Terraforming of Mars article. This is not a forum for general discussion of the article's subject. |
Article policies
|
Find sources: Google ( books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL |
Archives: 1, 2 |
This article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||||||||||||||||||||||||||||||||||||||
|
To-do list for Terraforming of Mars:
Priority 1 (top)
|
On 16 August 2009, Terraforming of Mars was linked from Digg, a high-traffic website. ( Traffic) All prior and subsequent edits to the article are noted in its revision history. |
This article links to one or more target anchors that no longer exist.
Please help fix the broken anchors. You can remove this template after fixing the problems. |
Reporting errors |
This article does not mention it at all. This single factor prevents Mars from ever being truly "Earth-like" due to it having only a third of Earth's gravity. I think the article misses the point and needs to consider the scope and motivations for terraforming. Humans settling there would have to cope with extremely low gravity. Weightlessness#Human health effects Gravity also has as many implications for Mars holding on to an atmosphere as the lack of a magnetic field. -- EvenGreenerFish ( talk) 02:38, 4 December 2012 (UTC)
Please see discussion on this topic below in the section headed "Dubious". Thanks. Rafflesgluft ( talk) 12:35, 19 January 2019 (UTC)
There seem to be a lot of artists impressions included in this article showing Mars looking almost like Earth with global oceans. However there is nothing in the article addressing this - it's complete science fiction. I think one image showing an ocean covered planet would be enough, perhaps along with some text saying that this is the kind of terraforming described in science fiction novels but that no proposed or suggested technology exists that would even hope to achieve something like this... and that anyway since the entire surface is toxic, such oceans presumably would be toxic too!
On a slightly different tack, another issue the article doesn't address is that one of the key ideas of terraforming is that a planet can be completely independent and not rely on supplies from Earth. Is it worth having a section on this? We haven't even managed to master sustainability here on Earth where we are overwhelmed with natural resources and natural cycles (water, oxygen, carbon, hydrogen cycles I mean), so I fear we have a long way to go before we can manage it on a toxic and hostile world such a Mars. Rafflesgluft ( talk) 15:13, 26 November 2018 (UTC)
Hello. Regarding temperature during dust storms: An advantage of the dust storm is that the temperature differences are not as extreme as they are on the surface of Mars. In addition, the swirled-up dust absorbs heat, thereby increasing the ambient temperature. [1] [2]
The paper you are citing states that temperature may drop back down by about 4K after the storm, due to albedo. Cheers, Rowan Forest ( talk) 16:07, 26 November 2018 (UTC)
References
The article currently states:
This has been marked as dubious, giving the reason:
There are three reasons I think the dubious marker is in error.
Firstly, the cited article does not "list Mars as heavy enough to hold on to oxygen", quite the reverse. Talking about Venus it notes that "....cause the atmosphere to be stripped almost entirely, much like that of Mars". I assume therefore that the claim is based on the below diagram at the top of the article, which applies only to thermal escape (the article gives two broad categories of atmospheric escape, thermal and non-thermal). In the diagram we can see that Mars sits in the middle of the band for oxygen and nitrogen, which is to say at its current temperature, some of the molecules will be travelling below escape velocity, some will be above it. This is based on the current average Martian temperature. However when the atmosphere is warmer than average due to seasonal and daily variations, a higher proportion of molecules will be travelling above escape velocity (which unlike the speed of the molecules does not change with temperature) and so more will escape during those periods. This is particularly important to note on Mars as the common global duststorms have the effect of warming the atmosphere itself (the dust suspended in the atmosphere is heated by the sun, rather than the ground being heated). I.e. both the diagram and article text support the statement that Mars doesn't have enough gravity to hold on to O2.
Secondly, the other class of escape mechanism (non-thermal) is particularly applicable to Mars where the atmosphere is so thin that when the solar wind is strongest, it blows all the way down to the planet surface. This imparts far more energy to molecules in the atmosphere than from the ambient temperature alone, causing far more of them to exceed escape velocity (potentially even the heavier ones such as CO2).
Finally, regardless of the theoretical side, despite the absolutely tiny amount of oxygen in the Marian atmosphere, enough escapes that we have direct observations of it happening. In fact a diagram recording oxygen escaping is already included in the Terraforming of Mars article:
For these three reasons it seems clear to me that the statement "Molecular oxygen (O2) only exists in trace amounts as Mars doesn't have enough gravity to hold on to it." is not dubious. I therefore propose to remove the dubious marker.
As an aside, the above doesn't take into account the fact that terraforming itself will increase the rate at which oxygen escapes. Currently the rate of escape is very small because there is so little oxygen left. The entire Martian atmosphere is so thin that in some contexts it would be classed as a vacuum. On the surface of Mars oxygen makes up just 0.145% of the 0.087 psi atmosphere (for comparison, on the surface of Earth oxygen is 21% of a 14.7 psi atmosphere). For this reason, terraforming seeks to drastically increase the amount of oxygen in the atmosphere. An increase of around 2.5 million % would be needed to reach Earth like levels. If you double the number of oxygen molecules in the atmosphere, then you'll double the number that are going faster than escape velocity and so double the rate of escape. Terraforming also aims to increase the temperature, which will move Mars to the right on the above diagram and also increase the rate of escape of oxygen (as well as the rest of the atmosphere). Presumably it was back when Mars was warmer and had liquid water on the surface that the majority of the water and oxygen escaped into space in the first place.
Rafflesgluft ( talk) 17:56, 28 November 2018 (UTC)
Done -- Rafflesgluft ( talk) 21:56, 5 December 2018 (UTC)
References
This section of the article needs some more development. Redirecting massive asteroids is in itself a questionable feat in the realm of science fiction, as we can't even deal (yet) with near earth asteroids that threaten our existence. Beyond that is the recognized inability of Mars .38 Earth gravity to create an atmosphere of light gases, like oxygen and nitrogen, which are necessary for life as we know it. . There are light gases in the Earths stratosphere, where the gravity is still almost 2/3rds greater than Mars. And none above it, because there is insufficient atmospheric pressure. And atmospheric pressure is caused by gravitational pull. Given that Mars has water and that a gravity of .38 Earth, how did Mars with such a low gravitational field even create an atmosphere, much less water and how can it be terraformed? Serious discussion is needed, otherwise the subject is in the realm of science fiction Oldperson ( talk) 23:21, 7 October 2019 (UTC)
Some mass estimates would be helpful. eg what is the current mass of Atmosphere_of_Mars? What mass of solid CO2 on the polar caps ? What mass of water ice in the polar caps ? - Rod57 ( talk) 12:09, 10 November 2020 (UTC)
[ https://www.popularmechanics.com/science/a32588385/elon-musk-terraform-mars-nuclear-missiles/ Cute idea, eh?] Should it be incorporated? Jim.henderson ( talk) 04:10, 6 May 2022 (UTC)
If I have not miscalculated, the partial pressure of CO2 on Mars is 15 times that on Earth, which means that adding Earthlike air would not suffice; most of Mars's CO2 would have to be removed or converted. Is that right? — Tamfang ( talk) 23:15, 25 March 2023 (UTC)
This is the
talk page for discussing improvements to the
Terraforming of Mars article. This is not a forum for general discussion of the article's subject. |
Article policies
|
Find sources: Google ( books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL |
Archives: 1, 2 |
This article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||||||||||||||||||||||||||||||||||||||
|
To-do list for Terraforming of Mars:
Priority 1 (top)
|
On 16 August 2009, Terraforming of Mars was linked from Digg, a high-traffic website. ( Traffic) All prior and subsequent edits to the article are noted in its revision history. |
This article links to one or more target anchors that no longer exist.
Please help fix the broken anchors. You can remove this template after fixing the problems. |
Reporting errors |
This article does not mention it at all. This single factor prevents Mars from ever being truly "Earth-like" due to it having only a third of Earth's gravity. I think the article misses the point and needs to consider the scope and motivations for terraforming. Humans settling there would have to cope with extremely low gravity. Weightlessness#Human health effects Gravity also has as many implications for Mars holding on to an atmosphere as the lack of a magnetic field. -- EvenGreenerFish ( talk) 02:38, 4 December 2012 (UTC)
Please see discussion on this topic below in the section headed "Dubious". Thanks. Rafflesgluft ( talk) 12:35, 19 January 2019 (UTC)
There seem to be a lot of artists impressions included in this article showing Mars looking almost like Earth with global oceans. However there is nothing in the article addressing this - it's complete science fiction. I think one image showing an ocean covered planet would be enough, perhaps along with some text saying that this is the kind of terraforming described in science fiction novels but that no proposed or suggested technology exists that would even hope to achieve something like this... and that anyway since the entire surface is toxic, such oceans presumably would be toxic too!
On a slightly different tack, another issue the article doesn't address is that one of the key ideas of terraforming is that a planet can be completely independent and not rely on supplies from Earth. Is it worth having a section on this? We haven't even managed to master sustainability here on Earth where we are overwhelmed with natural resources and natural cycles (water, oxygen, carbon, hydrogen cycles I mean), so I fear we have a long way to go before we can manage it on a toxic and hostile world such a Mars. Rafflesgluft ( talk) 15:13, 26 November 2018 (UTC)
Hello. Regarding temperature during dust storms: An advantage of the dust storm is that the temperature differences are not as extreme as they are on the surface of Mars. In addition, the swirled-up dust absorbs heat, thereby increasing the ambient temperature. [1] [2]
The paper you are citing states that temperature may drop back down by about 4K after the storm, due to albedo. Cheers, Rowan Forest ( talk) 16:07, 26 November 2018 (UTC)
References
The article currently states:
This has been marked as dubious, giving the reason:
There are three reasons I think the dubious marker is in error.
Firstly, the cited article does not "list Mars as heavy enough to hold on to oxygen", quite the reverse. Talking about Venus it notes that "....cause the atmosphere to be stripped almost entirely, much like that of Mars". I assume therefore that the claim is based on the below diagram at the top of the article, which applies only to thermal escape (the article gives two broad categories of atmospheric escape, thermal and non-thermal). In the diagram we can see that Mars sits in the middle of the band for oxygen and nitrogen, which is to say at its current temperature, some of the molecules will be travelling below escape velocity, some will be above it. This is based on the current average Martian temperature. However when the atmosphere is warmer than average due to seasonal and daily variations, a higher proportion of molecules will be travelling above escape velocity (which unlike the speed of the molecules does not change with temperature) and so more will escape during those periods. This is particularly important to note on Mars as the common global duststorms have the effect of warming the atmosphere itself (the dust suspended in the atmosphere is heated by the sun, rather than the ground being heated). I.e. both the diagram and article text support the statement that Mars doesn't have enough gravity to hold on to O2.
Secondly, the other class of escape mechanism (non-thermal) is particularly applicable to Mars where the atmosphere is so thin that when the solar wind is strongest, it blows all the way down to the planet surface. This imparts far more energy to molecules in the atmosphere than from the ambient temperature alone, causing far more of them to exceed escape velocity (potentially even the heavier ones such as CO2).
Finally, regardless of the theoretical side, despite the absolutely tiny amount of oxygen in the Marian atmosphere, enough escapes that we have direct observations of it happening. In fact a diagram recording oxygen escaping is already included in the Terraforming of Mars article:
For these three reasons it seems clear to me that the statement "Molecular oxygen (O2) only exists in trace amounts as Mars doesn't have enough gravity to hold on to it." is not dubious. I therefore propose to remove the dubious marker.
As an aside, the above doesn't take into account the fact that terraforming itself will increase the rate at which oxygen escapes. Currently the rate of escape is very small because there is so little oxygen left. The entire Martian atmosphere is so thin that in some contexts it would be classed as a vacuum. On the surface of Mars oxygen makes up just 0.145% of the 0.087 psi atmosphere (for comparison, on the surface of Earth oxygen is 21% of a 14.7 psi atmosphere). For this reason, terraforming seeks to drastically increase the amount of oxygen in the atmosphere. An increase of around 2.5 million % would be needed to reach Earth like levels. If you double the number of oxygen molecules in the atmosphere, then you'll double the number that are going faster than escape velocity and so double the rate of escape. Terraforming also aims to increase the temperature, which will move Mars to the right on the above diagram and also increase the rate of escape of oxygen (as well as the rest of the atmosphere). Presumably it was back when Mars was warmer and had liquid water on the surface that the majority of the water and oxygen escaped into space in the first place.
Rafflesgluft ( talk) 17:56, 28 November 2018 (UTC)
Done -- Rafflesgluft ( talk) 21:56, 5 December 2018 (UTC)
References
This section of the article needs some more development. Redirecting massive asteroids is in itself a questionable feat in the realm of science fiction, as we can't even deal (yet) with near earth asteroids that threaten our existence. Beyond that is the recognized inability of Mars .38 Earth gravity to create an atmosphere of light gases, like oxygen and nitrogen, which are necessary for life as we know it. . There are light gases in the Earths stratosphere, where the gravity is still almost 2/3rds greater than Mars. And none above it, because there is insufficient atmospheric pressure. And atmospheric pressure is caused by gravitational pull. Given that Mars has water and that a gravity of .38 Earth, how did Mars with such a low gravitational field even create an atmosphere, much less water and how can it be terraformed? Serious discussion is needed, otherwise the subject is in the realm of science fiction Oldperson ( talk) 23:21, 7 October 2019 (UTC)
Some mass estimates would be helpful. eg what is the current mass of Atmosphere_of_Mars? What mass of solid CO2 on the polar caps ? What mass of water ice in the polar caps ? - Rod57 ( talk) 12:09, 10 November 2020 (UTC)
[ https://www.popularmechanics.com/science/a32588385/elon-musk-terraform-mars-nuclear-missiles/ Cute idea, eh?] Should it be incorporated? Jim.henderson ( talk) 04:10, 6 May 2022 (UTC)
If I have not miscalculated, the partial pressure of CO2 on Mars is 15 times that on Earth, which means that adding Earthlike air would not suffice; most of Mars's CO2 would have to be removed or converted. Is that right? — Tamfang ( talk) 23:15, 25 March 2023 (UTC)