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A New Earth?
Here's an interesting link:
http://www.dailymail.co.uk/pages/liv...echnology.html ?in_article_id=450467&in_page_id=1965 I did a quick calculation of the surface gravity, based on the following inputs: M is the mass of Glise 581c which, according to the article, is 5 times as massive as Earth. The mass of Earth is 5.9736x10^24 kg. G = 6.6742x10^-11. The radius of Glise 581c, converted to meters, is r = 9,656,083. Therefo a = GM/r^2 = (6.6742x10^-11)[(5)(5.9736x10^24)]/(9656083)^2 = 21.4 m/s^2. On Earth, the acceleration, g, is 9.8 m/s^2, so on Glise 581c it is 21.4/9.8 = 2.1 g. That means if you weigh 200 lbs on Earth, you will weigh 420 lbs on the surface of Glise 581c. The question is, how many people would be able to walk around if their body weight suddenly doubled? And even among those who could, how many would be able to live that way? Sure, there are lot's of fat guys huffing around, but they all have desk jobs, or no jobs at all. Who could be a plumber, or a mechanic, or a construction worker, at that kind of body weight? Damn few, I'll bet. And without people to do those sorts of jobs, what kind of civilization could subsist there? Bottom line: as much as I would like a chance to live somewhere other than on Earth, I would walk past the desk where people were signing up to colonize Glise 581c without regrets. :-) Mitchell Jones ************************************************** *************** If I seem to be ignoring you, consider the possibility that you are in my killfile. --MJ |
#2
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A New Earth?
"Mitchell Jones" wrote in message
... Bottom line: as much as I would like a chance to live somewhere other than on Earth, I would walk past the desk where people were signing up to colonize Glise 581c without regrets. :-) What makes you think the inhabitants there would even consider you for immigration? ;-) |
#3
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A New Earth?
This all assumes that Gliese 581 C has the same composition as the Earth.
Then the figure for radius would be close to the mark. I assume it takes into account increased density due to greater interior pressure. However it quite likely has different composition. The planet may have formed beyond the "frost zone" for water and possibly other volatiles. In which case it would be considerably less dense, being comprised largely of a deep ocean of water. Its radius would be considerably larger than reported in the press and its surface gravity more comfortable. If the latter is true would you consider migrating there? The gravity problem would be eliminated but you would have to grow gills (assuming the planet has oxygen!). And big eyes too because Gliese doesn't emit much visible light. On Sun, 29 Apr 2007 18:15:29 -0500, Mitchell Jones wrote: |Here's an interesting link: | |http://www.dailymail.co.uk/pages/liv...echnology.html |?in_article_id=450467&in_page_id=1965 | |I did a quick calculation of the surface gravity, based on the following |inputs: | |M is the mass of Glise 581c which, according to the article, is 5 times |as massive as Earth. The mass of Earth is 5.9736x10^24 kg. G = |6.6742x10^-11. The radius of Glise 581c, converted to meters, is r = |9,656,083. | |Therefo | |a = GM/r^2 = (6.6742x10^-11)[(5)(5.9736x10^24)]/(9656083)^2 = 21.4 m/s^2. | |On Earth, the acceleration, g, is 9.8 m/s^2, so on Glise 581c it is |21.4/9.8 = 2.1 g. | |That means if you weigh 200 lbs on Earth, you will weigh 420 lbs on the |surface of Glise 581c. The question is, how many people would be able to |walk around if their body weight suddenly doubled? And even among those |who could, how many would be able to live that way? Sure, there are |lot's of fat guys huffing around, but they all have desk jobs, or no |jobs at all. Who could be a plumber, or a mechanic, or a construction |worker, at that kind of body weight? Damn few, I'll bet. And without |people to do those sorts of jobs, what kind of civilization could |subsist there? | |Bottom line: as much as I would like a chance to live somewhere other |than on Earth, I would walk past the desk where people were signing up |to colonize Glise 581c without regrets. :-) | |Mitchell Jones | |************************************************* **************** |If I seem to be ignoring you, consider the possibility |that you are in my killfile. --MJ ______________________________________________ * * _-_|\ * / \ Daggaz * \_.-._/--Sydney, Australia * v Email address is valid (no spamblocks) but temporary. I change it when spam levels become too high. |
#4
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A New Earth?
In article ,
Daggaz wrote: This all assumes that Gliese 581 C has the same composition as the Earth. Then the figure for radius would be close to the mark. I assume it takes into account increased density due to greater interior pressure. However it quite likely has different composition. The planet may have formed beyond the "frost zone" for water and possibly other volatiles. In which case it would be considerably less dense, being comprised largely of a deep ocean of water. Its radius would be considerably larger than reported in the press and its surface gravity more comfortable. If the latter is true would you consider migrating there? The gravity problem would be eliminated but you would have to grow gills (assuming the planet has oxygen!). And big eyes too because Gliese doesn't emit much visible light. ***{If I were willing to live underwater, I would stay here. Earth is mostly covered by oceans, after all, and we know there is oxygen here, and lots of visible light from the Sun. It wouldn't be very hard to construct an underwater habitat on the floor of the ocean, and plenty of air could be obtained by sending a float to the top that trailed a hose, supplemented by piston pumps as needed. Thus one could just as well "live free or die" on the bottom of one of Earth's oceans, as on the bottom of an ocean on Glise 581c. --MJ}*** On Sun, 29 Apr 2007 18:15:29 -0500, Mitchell Jones wrote: |Here's an interesting link: | |http://www.dailymail.co.uk/pages/liv...echnology.html |?in_article_id=450467&in_page_id=1965 | |I did a quick calculation of the surface gravity, based on the following |inputs: | |M is the mass of Glise 581c which, according to the article, is 5 times |as massive as Earth. The mass of Earth is 5.9736x10^24 kg. G = |6.6742x10^-11. The radius of Glise 581c, converted to meters, is r = |9,656,083. | |Therefo | |a = GM/r^2 = (6.6742x10^-11)[(5)(5.9736x10^24)]/(9656083)^2 = 21.4 m/s^2. | |On Earth, the acceleration, g, is 9.8 m/s^2, so on Glise 581c it is |21.4/9.8 = 2.1 g. | |That means if you weigh 200 lbs on Earth, you will weigh 420 lbs on the |surface of Glise 581c. The question is, how many people would be able to |walk around if their body weight suddenly doubled? And even among those |who could, how many would be able to live that way? Sure, there are |lot's of fat guys huffing around, but they all have desk jobs, or no |jobs at all. Who could be a plumber, or a mechanic, or a construction |worker, at that kind of body weight? Damn few, I'll bet. And without |people to do those sorts of jobs, what kind of civilization could |subsist there? | |Bottom line: as much as I would like a chance to live somewhere other |than on Earth, I would walk past the desk where people were signing up |to colonize Glise 581c without regrets. :-) | |Mitchell Jones | |************************************************* **************** |If I seem to be ignoring you, consider the possibility |that you are in my killfile. --MJ ______________________________________________ * * _-_|\ * / \ Daggaz * \_.-._/--Sydney, Australia * v Email address is valid (no spamblocks) but temporary. I change it when spam levels become too high. ************************************************** *************** If I seem to be ignoring you, consider the possibility that you are in my killfile. --MJ |
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A New Earth?
In article ,
"Greg Neill" wrote: "Mitchell Jones" wrote in message ... Bottom line: as much as I would like a chance to live somewhere other than on Earth, I would walk past the desk where people were signing up to colonize Glise 581c without regrets. :-) What makes you think the inhabitants there would even consider you for immigration? ;-) ***{Presumably if there were a desk at a spaceport on Earth, signing up people to colonize Glise 581c, the permission of the inhabitants would have already been obtained. When my ancestors signed up to colonize America, for example, the permission of the inhabitants had already been obtained by force of arms. Similar methods will doubtlessly be used from time to time, as mankind moves into space--assuming, of course, that we survive our present love affair with totalitarian slavery and, thus, do not go extinct. --MJ}*** ************************************************** *************** If I seem to be ignoring you, consider the possibility that you are in my killfile. --MJ |
#6
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A New Earth?
....even consider the sports... how could anyone play games and sports
there? swimming, baseball, cricket, races,.... it would be really be difficult to live there. the atmospheric pressure and gas mixture also is very important. Regards, Divij |
#7
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A New Earth?
On Mon, 30 Apr 2007 01:22:32 -0500, Mitchell Jones wrote:
|Thus one could just as well |"live free or die" on the bottom of one of Earth's oceans, as on the |bottom of an ocean on Glise 581c. You would need very advanced technology to build a habitat for the bottom of the ocean on Gliese 581C. That ocean would probably be thousands of kilometers deep, extending all the way to the rocky core, so the pressures and temperatures at the bottom will be huge. We can't even build a habitat for the bottom of the Marianas Trench, the lowest point in the Earth's oceans at 11km deep. A habitat that floats on the surface will be more practical. Or maybe Gliese 581C has an ice cap on the hemisphere facing away from its parent star, since it is most likely tidally locked. But it would be very dark and cold there. ______________________________________________ * * _-_|\ * / \ Daggaz * \_.-._/--Sydney, Australia * v Email address is valid (no spamblocks) but temporary. I change it when spam levels become too high. |
#8
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A New Earth?
On May 1, 8:52 am, Daggaz wrote:
On Mon, 30 Apr 2007 01:22:32 -0500, Mitchell Jones wrote: |Thus one could just as well |"live free or die" on the bottom of one of Earth's oceans, as on the |bottom of an ocean on Glise 581c. You would need very advanced technology to build a habitat for the bottom of the ocean on Gliese 581C. That ocean would probably be thousands of kilometers deep, extending all the way to the rocky core, so the pressures and temperatures at the bottom will be huge. We can't even build a habitat for the bottom of the Marianas Trench, the lowest point in the Earth's oceans at 11km deep. A habitat that floats on the surface will be more practical. Or maybe Gliese 581C has an ice cap on the hemisphere facing away from its parent star, since it is most likely tidally locked. But it would be very dark and cold there. ______________________________________________ * * _-_|\ * / \ Daggaz * \_.-._/--Sydney, Australia * v Email address is valid (no spamblocks) but temporary. I change it when spam levels become too high. i agree with you, pressure is very important, but still, the research is on. Regards, Divij |
#9
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A New Earth?
On Apr 30, 9:15 am, Mitchell Jones wrote:
Here's an interesting link: http://www.dailymail.co.uk/pages/liv...ogy/technology.... ?in_article_id=450467&in_page_id=1965 I did a quick calculation of the surface gravity, based on the following inputs: M is the mass of Glise581cwhich, according to the article, is 5 times as massive as Earth. The mass of Earth is 5.9736x10^24 kg. G = 6.6742x10^-11. The radius of Glise581c, converted to meters, is r = 9,656,083. I hope you realize that noone has a clue what the radius of 581c is. The number 1.5 is someone's guess based on the mass and the hope that the planet is rocky. A more serious problem is that the planet receives 244% of the star light that Earth does, or about 25% more than Venus. If it had water it would be way past the runaway greenhouse threshold. I estimate the surface temperature assuming an equilibrium steam atmosphere of about 830K. --mt. |
#10
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A New Earth?
"Market Theory" wrote in message
oups.com... On Apr 30, 9:15 am, Mitchell Jones wrote: Here's an interesting link: http://www.dailymail.co.uk/pages/liv...ogy/technology.... ?in_article_id=450467&in_page_id=1965 I did a quick calculation of the surface gravity, based on the following inputs: M is the mass of Glise581cwhich, according to the article, is 5 times as massive as Earth. The mass of Earth is 5.9736x10^24 kg. G = 6.6742x10^-11. The radius of Glise581c, converted to meters, is r = 9,656,083. I hope you realize that noone has a clue what the radius of 581c is. The number 1.5 is someone's guess based on the mass and the hope that the planet is rocky. A more serious problem is that the planet receives 244% of the star light that Earth does, or about 25% more than Venus. If it had water it would be way past the runaway greenhouse threshold. I estimate the surface temperature assuming an equilibrium steam atmosphere of about 830K. Your estimate does not accord with the estimate made by the investigators, who put the temperature in the range of liquid water. |
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