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  #12  
Old August 8th 18, 12:34 PM posted to sci.space.policy
Jeff Findley[_6_]
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In article ,
says...

On Thursday, August 2, 2018 at 7:34:27 AM UTC-4, Jeff Findley wrote:
In article ,
says...

Terraforming Mars is one of those religious arguments, anyhow.


True. But my guess is that Mars will prove lifeless. If that's the
case, who's going to object to terraforming a lifeless planet?

Nothing fundamental in physics to stop humans from doing it. It will
surely take centuries or more to do it, but there should be more than
enough material in the solar system to do it. Mostly Mars needs
volatiles to recreate a thicker atmosphere. Once you get it up to 5
psi, you can walk around in breathing masks and (relatively) normal
clothing.


I forget how many octillion tons of oxygen it would take, but the
problem is getting it there in the needed quantities and then keeping
it there. Apparently nearly all of its atmosphere (even assuming it was
Earthlike at one time) has long since departed due to the effects of
gravity and solar radiation.


Keeping it there isn't much of a problem. In the short term (hundreds
of thousands of years) it won't lose enough to matter. A few more
Kuiper belt objects would make up for the loss.

In the long term, you put a giant electromagnet between Mars and the sun
in order to produce an artificial magnetic field to mimic the protection
earth's magnetic field gives it. Note from above this gives you
hundreds of thousands of years to perfect that tech and scale it up to
sufficient size.

The arguments against terraforming Mars sound a lot like the myriad of
arguments against heavier than air travel before the Wright Brothers
successfully demonstrated that it was possible. Yet a few weeks ago, I
flew to Shanghai and back for a week long business trip which is a 12
hour time zone difference from where I live, so roughly half way around
the planet. And that was only a bit over one hundred years later.
Terraforming is on a much bigger timescale, so we have a much longer
time frame to perfect the tech necessary to complete the task.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #13  
Old August 8th 18, 12:36 PM posted to sci.space.policy
Jeff Findley[_6_]
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Default Discussion on sci.space.science

In article ,
says...
I forget how many octillion tons of oxygen it would take, but the
problem is getting it there in the needed quantities and then keeping
it there.


Not many octillions, less than a trillionth of an octillion tons. An
octillion is a somewhat large number (that's using the short scale, the
long scale would be even worse). But yes, it is true that many trillion
tons of O2 is a lot of O2.

Keeping it there isn't really the problem. It will be blown away by
solar wind as Mars' original atmosphere was. But that happens on a time
scale of millions of years. If you can't replenish it on that time
scale, it basically means that you couldn't put it there in the first
place. No one is going to start adding O2 to Mars with the plan of
having completed the job in a million years.


A trillionth of an octillion tons would be in the quintillions.
Nobody knows what did or would take place in millions of years,
as nobody has any such observational span.


Actually you can estimate the rate of loss over time based on how much
of an atmosphere is there today. You can also estimate it based on
other factors like how big Mars is, how strong the solar wind is at that
distance, and etc. It's not like we're completely clueless here.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #14  
Old August 9th 18, 03:00 AM posted to sci.space.policy
Scott M. Kozel[_2_]
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On Wednesday, August 8, 2018 at 7:34:07 AM UTC-4, Jeff Findley wrote:
In article ,
says...

I forget how many octillion tons of oxygen it would take, but the
problem is getting it there in the needed quantities and then keeping
it there. Apparently nearly all of its atmosphere (even assuming it was
Earthlike at one time) has long since departed due to the effects of
gravity and solar radiation.


Keeping it there isn't much of a problem. In the short term (hundreds
of thousands of years) it won't lose enough to matter. A few more
Kuiper belt objects would make up for the loss.


So the idea is that they spend a decade or so "pumping it up" to Earthlike
atmosphere, and then that will last for millions of years before it leaks
away?

In the long term, you put a giant electromagnet between Mars and the sun
in order to produce an artificial magnetic field to mimic the protection
earth's magnetic field gives it. Note from above this gives you
hundreds of thousands of years to perfect that tech and scale it up to
sufficient size.

The arguments against terraforming Mars sound a lot like the myriad of
arguments against heavier than air travel before the Wright Brothers
successfully demonstrated that it was possible. Yet a few weeks ago, I
flew to Shanghai and back for a week long business trip which is a 12
hour time zone difference from where I live, so roughly half way around
the planet. And that was only a bit over one hundred years later.
Terraforming is on a much bigger timescale, so we have a much longer
time frame to perfect the tech necessary to complete the task.


Really. Heavier than air travel was a matter of engineering developments
that provided a powerful enough engine and an airframe that could handle
the 100+ mph speeds that would keep it airborne. A 600-pound machine.
The theory was known for hundreds of years if not thousands.

The arguments against terraforming Mars are like trying to explain to
someone how the Sun can be a hydrogen bomb but there is so much mass there
that gravity alone is sufficient to create the temperatures needed for
hydrogen fusion, and this hydrogen fusion process will last for at least 5 billion more years before it runs out of fuel.
  #15  
Old August 9th 18, 12:11 PM posted to sci.space.policy
Alain Fournier[_3_]
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On Aug/8/2018 at 10:00 PM, Scott M. Kozel wrote :
On Wednesday, August 8, 2018 at 7:34:07 AM UTC-4, Jeff Findley wrote:
In article ,
says...

I forget how many octillion tons of oxygen it would take, but the
problem is getting it there in the needed quantities and then keeping
it there. Apparently nearly all of its atmosphere (even assuming it was
Earthlike at one time) has long since departed due to the effects of
gravity and solar radiation.


Keeping it there isn't much of a problem. In the short term (hundreds
of thousands of years) it won't lose enough to matter. A few more
Kuiper belt objects would make up for the loss.


So the idea is that they spend a decade or so "pumping it up" to Earthlike
atmosphere, and then that will last for millions of years before it leaks
away?


That's about it. I would change the word decade for century. There is
also a little more to terraforming Mars than adding an atmosphere, but
that is the bulk of it. You would also want to add water, which would
probably be a side effect of adding the atmosphere. Then you want to
grow plants. Before you can say that Mars has been terraformed you want
plants to have been growing plants for a century to add O2 to the
atmosphere and a layer of topsoil.


Alain Fournier
  #16  
Old August 9th 18, 12:46 PM posted to sci.space.policy
Jeff Findley[_6_]
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Posts: 2,307
Default Discussion on sci.space.science

In article ,
says...

On Wednesday, August 8, 2018 at 7:34:07 AM UTC-4, Jeff Findley wrote:
In article ,
says...

I forget how many octillion tons of oxygen it would take, but the
problem is getting it there in the needed quantities and then keeping
it there. Apparently nearly all of its atmosphere (even assuming it was
Earthlike at one time) has long since departed due to the effects of
gravity and solar radiation.


Keeping it there isn't much of a problem. In the short term (hundreds
of thousands of years) it won't lose enough to matter. A few more
Kuiper belt objects would make up for the loss.


So the idea is that they spend a decade or so "pumping it up" to Earthlike
atmosphere, and then that will last for millions of years before it leaks
away?


More like hundreds or thousands of years, but yes. In the short term,
losing atmosphere is a manageable problem. In the long term, you'd
likely want a technological solution (like a strategically placed giant
magnet) that would reduce the rate of atmosphere loss.

In the long term, you put a giant electromagnet between Mars and the sun
in order to produce an artificial magnetic field to mimic the protection
earth's magnetic field gives it. Note from above this gives you
hundreds of thousands of years to perfect that tech and scale it up to
sufficient size.

The arguments against terraforming Mars sound a lot like the myriad of
arguments against heavier than air travel before the Wright Brothers
successfully demonstrated that it was possible. Yet a few weeks ago, I
flew to Shanghai and back for a week long business trip which is a 12
hour time zone difference from where I live, so roughly half way around
the planet. And that was only a bit over one hundred years later.
Terraforming is on a much bigger timescale, so we have a much longer
time frame to perfect the tech necessary to complete the task.


Really. Heavier than air travel was a matter of engineering developments
that provided a powerful enough engine and an airframe that could handle
the 100+ mph speeds that would keep it airborne. A 600-pound machine.
The theory was known for hundreds of years if not thousands.


This really isn't any different. The theory is rock solid. You're
essentially recreating the magnetic shielding that the earth has thanks
to its magnetic shield. This is not at all different than heavier than
air flight before it was proven possible by the Wright Brothers.

The details needed to create such a huge magnetic field are "just
engineering problems to solve". Granted it may take hundreds or even
thousands of years to actually implement the solution. But, that's
still a very short amount of time when you consider the actual rate of
atmosphere loss you'd have on a terraformed Mars without any magnetic
shielding.

People that say terraforming Mars would be impossible are just like
those people that used to say "If God had meant man to fly, he'd have
given man wings".

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #17  
Old August 9th 18, 07:49 PM posted to sci.space.policy
Scott M. Kozel[_2_]
external usenet poster
 
Posts: 160
Default Discussion on sci.space.science

On Thursday, August 9, 2018 at 7:46:41 AM UTC-4, Jeff Findley wrote:
In article ,
says...

Heavier than air travel was a matter of engineering developments
that provided a powerful enough engine and an airframe that could handle
the 100+ mph speeds that would keep it airborne. A 600-pound machine.
The theory was known for hundreds of years if not thousands.


This really isn't any different. The theory is rock solid. You're
essentially recreating the magnetic shielding that the earth has thanks
to its magnetic shield. This is not at all different than heavier than
air flight before it was proven possible by the Wright Brothers.


Building a 600-pound machine when the metallurgy and engineering was
at a point to sustain 100-mph flight, is rather simple compared to
building a magnet that weighs quadrillions or quintillions (or whatever)
of tons.

A 300-ton Boeing 777 is also a speck in comparison.

The details needed to create such a huge magnetic field are "just
engineering problems to solve". Granted it may take hundreds or even
thousands of years to actually implement the solution. But, that's
still a very short amount of time when you consider the actual rate of
atmosphere loss you'd have on a terraformed Mars without any magnetic
shielding.

People that say terraforming Mars would be impossible are just like
those people that used to say "If God had meant man to fly, he'd have
given man wings".


Possibly the theory behind warp drive is "rock solid" as well, if you are
looking at thousands of years until actually implementing the solution.

Assuming that quintillions of tons of oxygen can be found and moved to Mars.

The Sun example is apropos. It is hard to humanly comprehend the amount of
mass that we are talking about.
  #18  
Old August 9th 18, 09:52 PM posted to sci.space.policy
Fred J. McCall[_3_]
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Posts: 10,018
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JF Mezei wrote on Thu, 9 Aug 2018
14:24:38 -0400:

On 2018-08-08 07:36, Jeff Findley wrote:

Actually you can estimate the rate of loss over time based on how much
of an atmosphere is there today. You can also estimate it based on
other factors like how big Mars is, how strong the solar wind is at that
distance, and etc. It's not like we're completely clueless here.


Since there is knowledge that Mars used used to have thicker atmosphere
but lost it over time, is there a point is going through efforts to add
more gas to its atnopphere if the extra gas will be lost anyways ?


It's all about time scales. Can you add enough gas fast enough and
will it lose it slowly enough to be worthwhile.

Everything we build is going to decay. This wouldn't be any
different.


--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw
  #19  
Old August 10th 18, 01:05 PM posted to sci.space.policy
Jeff Findley[_6_]
external usenet poster
 
Posts: 2,307
Default Discussion on sci.space.science

In article ,
says...

On Thursday, August 9, 2018 at 7:46:41 AM UTC-4, Jeff Findley wrote:
In article ,
says...

Heavier than air travel was a matter of engineering developments
that provided a powerful enough engine and an airframe that could handle
the 100+ mph speeds that would keep it airborne. A 600-pound machine.
The theory was known for hundreds of years if not thousands.


This really isn't any different. The theory is rock solid. You're
essentially recreating the magnetic shielding that the earth has thanks
to its magnetic shield. This is not at all different than heavier than
air flight before it was proven possible by the Wright Brothers.


Building a 600-pound machine when the metallurgy and engineering was
at a point to sustain 100-mph flight, is rather simple compared to
building a magnet that weighs quadrillions or quintillions (or whatever)
of tons.

A 300-ton Boeing 777 is also a speck in comparison.


It's "just" a question of scale. Again, we went from a first heavier
than air flight measured in yards to Boeing 777s flying half way around
the world in about 100 years. So, building a big magnet to shield Mars
ought to be something we can do in several hundreds or several thousands
of years. Tech keeps getting better and better. Manufacturing keeps
getting better and better. We have the entire asteroid belt to use for
raw material if we have to. I don't see any fundamental show-stoppers
given much time and effort.

The alternative is to keep dropping comets on Mars, from time to time,
to make up for the loss. Either way, loss of atmosphere is something to
deal with on a very, very long timescale and really is not a show-
stopper for terraforming Mars.

The details needed to create such a huge magnetic field are "just
engineering problems to solve". Granted it may take hundreds or even
thousands of years to actually implement the solution. But, that's
still a very short amount of time when you consider the actual rate of
atmosphere loss you'd have on a terraformed Mars without any magnetic
shielding.

People that say terraforming Mars would be impossible are just like
those people that used to say "If God had meant man to fly, he'd have
given man wings".


Possibly the theory behind warp drive is "rock solid" as well, if you are
looking at thousands of years until actually implementing the
solution.


Not the same thing at all. We know how to build electromagnets. We use
them all the time. They also keep getting better with each passing
year. Electric motors were crap for electric cars in the 1970s, but now
they're quite good and both hybrid and electric cars which use them are
quite common.

Same thing with the Wright Brothers. We'd been building gliders for
centuries before their first powered flight. "All" they did was to
miniaturize and lightweight a gasoline motor so that it became a viable
means to add power to a glider. I put "all" in quotes because their
achievement was quite historical and in many ways made our modern
society possible. But from a physics point of view, both Langley and
the Wright Brothers knew that this was absolutely possible. It was just
a question of who would achieve the goal first.

Warp drive has not been demonstrated at all. Not the same thing at all.

Assuming that quintillions of tons of oxygen can be found and moved to Mars.


The Kuiper belt has a total mass estimated to range between 1/25 and
1/10 the mass of the Earth. Mass of Earth is about 6 * 10^24 kg. We'll
also have some losses due to using some of the mass of the objects as
propellant. Also not all the mass of the objects will be volatiles, so
we'll have to discount that as well. So let's say we have 5 * 10^21 kg
of volatiles we can "easily" get to Mars.

The mass of earth's atmosphere is "only" about 5 * 10^18 kg. So, I
think we're good considering the orders of magnitude we're talking about
here. Again, even if the magnet thing doesn't pan out, just keep
dropping Kuiper belt objects from time to time. We've got the mass in
the Kuiper belt to spare.

The Sun example is apropos. It is hard to humanly comprehend the amount of
mass that we are talking about.


Yeah, the numbers we're talking about are huge.

Jeff

--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #20  
Old August 10th 18, 04:47 PM posted to sci.space.policy
Greg \(Strider\) Moore
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Posts: 752
Default Discussion on sci.space.science

"Jeff Findley" wrote in message
...

In article ,
says...

On Thursday, August 9, 2018 at 7:46:41 AM UTC-4, Jeff Findley wrote:
In article ,
says...

Heavier than air travel was a matter of engineering developments
that provided a powerful enough engine and an airframe that could
handle
the 100+ mph speeds that would keep it airborne. A 600-pound
machine.
The theory was known for hundreds of years if not thousands.

This really isn't any different. The theory is rock solid. You're
essentially recreating the magnetic shielding that the earth has thanks
to its magnetic shield. This is not at all different than heavier than
air flight before it was proven possible by the Wright Brothers.


Building a 600-pound machine when the metallurgy and engineering was
at a point to sustain 100-mph flight, is rather simple compared to
building a magnet that weighs quadrillions or quintillions (or whatever)
of tons.

A 300-ton Boeing 777 is also a speck in comparison.


It's "just" a question of scale. Again, we went from a first heavier
than air flight measured in yards to Boeing 777s flying half way around
the world in about 100 years. So, building a big magnet to shield Mars
ought to be something we can do in several hundreds or several thousands
of years. Tech keeps getting better and better. Manufacturing keeps
getting better and better. We have the entire asteroid belt to use for
raw material if we have to. I don't see any fundamental show-stoppers
given much time and effort.

The alternative is to keep dropping comets on Mars, from time to time,
to make up for the loss. Either way, loss of atmosphere is something to
deal with on a very, very long timescale and really is not a show-
stopper for terraforming Mars.

The details needed to create such a huge magnetic field are "just
engineering problems to solve". Granted it may take hundreds or even
thousands of years to actually implement the solution. But, that's
still a very short amount of time when you consider the actual rate of
atmosphere loss you'd have on a terraformed Mars without any magnetic
shielding.

People that say terraforming Mars would be impossible are just like
those people that used to say "If God had meant man to fly, he'd have
given man wings".


Possibly the theory behind warp drive is "rock solid" as well, if you are
looking at thousands of years until actually implementing the
solution.


Not the same thing at all. We know how to build electromagnets. We use
them all the time. They also keep getting better with each passing
year. Electric motors were crap for electric cars in the 1970s, but now
they're quite good and both hybrid and electric cars which use them are
quite common.

Same thing with the Wright Brothers. We'd been building gliders for
centuries before their first powered flight. "All" they did was to
miniaturize and lightweight a gasoline motor so that it became a viable
means to add power to a glider. I put "all" in quotes because their
achievement was quite historical and in many ways made our modern
society possible. But from a physics point of view, both Langley and
the Wright Brothers knew that this was absolutely possible. It was just
a question of who would achieve the goal first.


Umm, I'd say it was more than that, thought that was a big part of it.

The ability to control via wing-warping was sort of new.
But also their realization that a prop really needed an airfoil shape also
made a difference (not sure but guessing it helped make their tiny gasoline
engine setup efficient enough to actually work).

So a bit more than just the motor :-)

But agreed, it was basically an engineering problem.

Warp drive.. it s bit more.
Warp drive has not been demonstrated at all. Not the same thing at all.

Assuming that quintillions of tons of oxygen can be found and moved to
Mars.


The Kuiper belt has a total mass estimated to range between 1/25 and
1/10 the mass of the Earth. Mass of Earth is about 6 * 10^24 kg. We'll
also have some losses due to using some of the mass of the objects as
propellant. Also not all the mass of the objects will be volatiles, so
we'll have to discount that as well. So let's say we have 5 * 10^21 kg
of volatiles we can "easily" get to Mars.

The mass of earth's atmosphere is "only" about 5 * 10^18 kg. So, I
think we're good considering the orders of magnitude we're talking about
here. Again, even if the magnet thing doesn't pan out, just keep
dropping Kuiper belt objects from time to time. We've got the mass in
the Kuiper belt to spare.

The Sun example is apropos. It is hard to humanly comprehend the amount
of
mass that we are talking about.


Yeah, the numbers we're talking about are huge.

Jeff


--
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http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net
IT Disaster Response -
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