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#76 2016-10-06 11:12:38

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Because that's what were talking about! How many people fly in airplanes? Millions. Why is the idea about millions of people traveling in space such an incredible idea to you, just because we're not doing it now? Million of people fly in airplanes, you for you it seems space travel is mostly for audiences watching live pictures on their televisions. For you an astronaut is a celebrity figure who signs autographs, that has got to change, what's called The Right Stuff has go to change. If you need to be a super genius at the pinnacle of your career and be hired by the government to go into space, this is not a real and true space age. Suppose President Thomas Jefferson wanted to create an Aeronautical Agency to support balloon flights and taxpayer expense. Thomas Jefferson had seen balloon flights in France, wouldn't that be comparable to what NASA is doing today? We are in the hot air balloon age of space flight. Most people in the early 19th century didn't fly at all. though a few did, the Wright Brothers weren't the first.

Modern flight began in 1783 when Joseph-Michael and Jacques-Ètienne Montgolfier engineered the first hot-air balloon flights. On Oct. 15, 1783, the Montgolfiers brothers launched a balloon on a tether with Jean-François Pilâtre de Rozier, a chemistry and physics teacher, as the passenger. In that era, nobody knew if a person could withstand the rigors of being up in the air, so a previous flight had included animals, to see if they survived. They did, as did de Rozier. Later that year, the first untethered flight was made.

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#77 2016-10-06 11:13:07

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Terraformer wrote:

Why are you so fixated on 1 million to Mars? I don't think anyone here is actually arguing for that...

Because that's the title of this thread.

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#78 2016-10-06 11:44:51

Terraformer
Member
From: Ceres
Registered: 2007-08-27
Posts: 3,821
Website

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

So we don't have to make everything from scratch and we can actually bring machines and other pre-made things to Mars?

Ye gods, what did you think people were saying? Have you even been bothering to read our posts?


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#79 2016-10-06 11:58:56

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,438

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Dook wrote:
kbd512 wrote:
Dook wrote:

Why send plastic bowls to Mars when we can just make one easily?  Because you can't make one easily on Mars.  You said you need a kiln, and you have to use electricity, and you have to use water, and you didn't mention the habitat needed to do all of this in.  Are you going to do this in the Mars Hab, the rocket than landed you there on Mars?  Or, are you going to build a separate Hab and then make bowls in it?

Obviously you'd have to send several habitat modules to Mars if you're going to send the spaceship back to Earth.  Is there some specific reason why we can't put a kiln in one of the habitat modules modules?  If you obtain sulphur from Mars, you don't need a kiln of the type we commonly use on Earth, or water, and you can make the bowl in a vacuum.  This has been tested here on Earth.  You still need a grinder to grind the regolith, but I'm pretty sure you don't need a major manufacturing facility to grind regolith into powder and there seems to be an awful lot of it just sitting on the surface for anyone with a shovel to scoop up.

Dook wrote:

Can't easily make a nuclear reactor on Mars?  I didn't say you could, in fact, I was arguing that something as simple as a bowl is going to be too complex to manufacture on Mars for a very long time.

Since testing has already proven that a bowl can be made in a vacuum using materials already identified on Mars with Martian regolith simulant, we're going to assume that actual testing is more valuable information than Dook's say-so.

Dook wrote:

A reactor scaled to the size needed for a startup colony is not an immovable sized object?  I didn't say it was.  You might want to look up RTG reactors on Wiki and then you will get an idea of their size and power output.  I think the biggest one is around 1,000 lbs.

When I said nuclear reactor, I thought most people would infer "fission reactor".  If that point was not clear, I want to land a CO2 cooled nuclear fission reactor on Mars.  A CO2 cooled 100kWe reactor core might weigh as little as 1t, although the weight with shielding will be substantially more than that (5t to 7t), but I think a 500kWe or 1MWe reactor is probably more useful for a startup colony.

A 50-100 kWe Gas-cooled Reactor For Use On Mars

Dook wrote:

I didn't say that a rocket that can put a payload on Mars can't be used for exploration.  It can put four people on Mars with enough supplies to last them about 500 days.  Sending 100 people to Mars anytime soon is not exploration, it's a death sentence.

If we just send 100 people to Mars without any infrastructure delivered and ready to use before they arrive, they're as good as dead.  At the risk of lending any credence to such a litany of straw man arguments, we agree here.

Dook wrote:

I know NASA is planning on going back to the moon.  To me it's a waste of time but I'm not in charge of what they do.  As I said, I want Mars Direct.

I do want to send exploration crews to the surface to find potential locations for colonies.  I laid out an entire mobile surface exploration mission architecture for doing that in various other threads here.

Dook wrote:

When I said I don't care about timelines I meant I'm not in a hurry to risk peoples lives to make money doing something completely unnecessary like Elon Musk.

Simply exploring Mars is completely unnecessary and will, in fact, risk peoples' lives.  And yet, you still want to send people there.

Dook wrote:

Uhh, you're missing the point, it's not going to take one or two or three or four food shipments, it's going to take constant resupply of food and water.

Potential resupply issues are precisely why ice mining and hydroponic farming should be the very first habitability experiments conducted there.  NASA and other space agencies have already sent a good number of sophisticated robotic probes there.  There's no reason for humans to even attempt to land there if there's no intent to live there.

Dook wrote:

It would also be prudent to start growing food right away?

Yes

Dook wrote:

Where are you going to grow it?

In a hydroponics module.

Omega Hydroponic Garden Gets Five Times As Much Food Per Watt

Dook wrote:

Please give details on the size and material of the greenhouse and how you're going to keep the fruit and vegetables from freezing at night?

5M diameter x 10M high, vertically emplaced in the Martian regolith.  It will be powered by a CO2 cooled nuclear fission reactor connected to the tunnel boring machine that digs the vertical pits for these modules.

The greenhouse is made from the same materials as a Bigelow Aerospace inflatable module since that's what I want to use.  The MMOD protection clearly isn't required since these modules will be buried in the ground on Mars and stored in cargo containers for transport to the surface.

Dook wrote:

Also, if you could explain how much water it's going to take to grow the plants and where you are going to get the water from?

We're going to get the water from ice mining and I stated my desire to send surface exploration missions ahead of the colony to find resources.  If we have a fission reactor, we're not going to run out of power or heat.

Dook wrote:

Also, most plants don't produce complete protein so what is your protein source going to be?

Hmm...

8 Plant Foods that Contain Complete Proteins (For Vegans)

Dook wrote:

What's my idea of contributing to humanity?  I do what I do.  If that's not enough for some people, tough.

Will you make an attempt to contribute something to this thread apart from straw man arguments about how difficult something is?

Will you start Dook Direct in its own thread so we can discuss your exploration plans there?

So, one of the first Mars Habs would be devoted to making ceramics on Mars.  Okay, it's possible.  Not sure how you mold the Mars material into a bowl shape without it being wet.  Also, finding a clay deposit is going to take some time, time = oxygen/food/water.  You can't just use sand. 

The CO2 nuclear reactor sounds good.  How are you going to use it's heat to warm the Mars surface to evaporate the water and capture it?
Exploring Mars will risk people's live?  Of course it will, I'm not against risk.  Space travel is inherently risky.  Trying to force 1 million people to Mars in a hurried schedule is too much risk, even if they want to go.  We don't support suicide.     

There's no reason for humans to even attempt to land on Mars if there is no intent to live there?  So we should not have landed on the moon then?

Your greenhouse is going to be 16' x 32'?  You say it will be powered by your nuclear reactor?  What power do you need in a greenhouse?  LED lights?  Electric heaters?

So you're going to use a tunnel boring machine to dig some kind of tunnel for the greenhouse?  How much does the tunnel boring machine weigh and how many launches does it take to get it to Mars?  How do you move it on Mars, with what kind of truck?  How do you lift it on the truck bed and then how do you get it off the truck bed? 

So you're inflatable greenhouse is going to be buried?  Uhh, how does it stay inflated after it's buried?

So, you've got a few exploration habitats spread out on Mars, not sure how many you planned, just guessing it's about 10.  You have a hydroponics greenhouse somewhere that can supply some vegetables, no fruit.  How do you get the food out to the exploration habs?  You have a hab that makes ceramic bowls and cups.  I guess they are saved until more people arrive.  Where is the MOXIE unit? 

Will I make an attempt to contribute to the 1 million people on Mars in 50 years thread?  I am contributing.  Have you ever heard of peer review?
       
Will I start Dook Direct thread?  There is no Dook Direct.  There's Mars Direct, which Elon Musk is using only he's enlarged it substantially, if it works.  The heavy Falcon seems reasonable.  The super huge ITS is not.

I've already answered all the questions you've asked in this post in another thread regarding how you could realistically use ITS to start a colony.  Falcon Heavy is not a realistic launch vehicle for starting a colony, I stated that, and you ignored that statement.  My plan requires 2 ITS launches.  Go read about it.

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#80 2016-10-06 12:35:19

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Terraformer wrote:

So we don't have to make everything from scratch and we can actually bring machines and other pre-made things to Mars?

Ye gods, what did you think people were saying? Have you even been bothering to read our posts?

Have I read your posts?  You mean the posts about how to make ceramic bowls on Mars so we don't have to fly in a box of plastic ones?

Are those the posts you're wondering about?

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#81 2016-10-06 13:01:49

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Dook wrote:
Terraformer wrote:

So we don't have to make everything from scratch and we can actually bring machines and other pre-made things to Mars?

Ye gods, what did you think people were saying? Have you even been bothering to read our posts?

Have I read your posts?  You mean the posts about how to make ceramic bowls on Mars so we don't have to fly in a box of plastic ones?

Are those the posts you're wondering about?

Yes.  Small pieces of the puzzle.  The fact is that nobody knows straight off how we will go about manufacturing every product that we need on the surface of Mars.  None of us has the time to work all that out.  This site is basically a hobby for bored engineers, most of them with day jobs and family.  The fact that we do not have answers straight away does not mean they don't exist.  It means that none of us can afford the time for industrial design projects.

The fact remains that with CAD, CNC machines and 3D printers, we can potentially build up a sizable manufacturing capability on Mars fairly quickly.  With a small variety of raw materials from local sources, most of the components for base building can be manufactured locally from day 1.

As I have said before, the number 1 limitation on the rate of population increase for a Mars colony will be finding meaningful exports that can be sent back to Earth to pay for what is needed by the base.  Without that, any talk of a base with permanent population of more than 100 is cloud cuckoo land.  On the other hand, find something that can make big bucks Earthside and getting a million people to Mars is not unrealistic, because big companies will fund emigration to build the labour force they need.  In just a couple of hundred years, the US population swelled from zero to 300million.  In the same time frame, the population of Greenland went from almost zero to...almost zero.  The difference?  The US had resources that could be exported for profits and could be used to build industries that make products that sell for even more profit.  Our ability to create a Martian civilisation depends upon replicating this model.  If we can, then the difficulties of surviving and prospering on a barren planet will be overcome.  If we can't, then no amount of innovation will help build a Mars colony beyond a handful of people.

Last edited by Antius (2016-10-06 13:14:44)

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#82 2016-10-06 13:50:49

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,464
Website

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Please see what I posted in the "Musk's Plans for Mars" thread,  post #180 dated 10-6-16.  It specifically applies to this thread as well. 

Looking solely at mineral extraction is the wrong model for planning colonization.  Producing and exporting intermediate or finished products from local resources is the right model. 

Intellectual property is currently the easiest (and cheapest) thing to transmit across interplanetary distances. 

GW

Last edited by GW Johnson (2016-10-06 13:56:21)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#83 2016-10-06 14:09:12

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,438

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Dook wrote:

Mars actually is extremely dry in most places.  Ice is not water and the ice on Mars is mixed with frozen CO2.

Most places is not every place.  There's a difference between something that's generally true and universally true.  However, MRO says you're wrong and once again, we're going with actual data from NASA over Dook's say-so.

Ice is not water?  They must have taught science class a bit differently where you went to school.

Dook wrote:

RTG's don't require any more shielding?  I didn't say they did, what I said was that they need to be moved away from the base.  That's why I asked what kind of reactor that you were talking about because it seemed as if you wanted to use heat from it to heat the Mars surface and RTG's do not provide heat to an external place.

Ah, what the hell.  I find your responses amusing and ignorant enough that I'll attempt to educate you one more time.

A RTG is not a radiation hazard to humans in close proximity wearing T-shirts and jeans, never mind space suits.  There's no reason to move it away from the base.  It poses no radiation hazard to the astronauts living and working in close proximity to the device.  Even if you opened it up and dumped the fuel out on the ground, you'd have to do something ridiculously stupid like try to pick up the Pu pellets off the ground with your hands to suffer any radiation exposure greater than the background radiation exposure you're constantly receiving while standing on the surface of the planet.

NASA engineers stand right next to a RTG without issue on a routine basis when they're working on those devices.  The only special clothing worn is intended to prevent cuts or thermal burns and to prevent biological contamination of the RTG.

A RTG can't be turned on or off like a fission reactor because it's not designed as a reactor.  RTG's contain decaying radioactive isotopes that generate a lot of heat as a result of the decay of the radioactive isotope and that heat is used to generate electricity using a thermocouple.  Thus the RTG is a radioactive decay-powered thermocouple.  Fission reactors or "nuclear reactors" generate heat by splitting atoms.  There is no comparison, none whatsoever, between the radiation that fissioning Pu generates and the radiation generated through decay of the Pu-238 isotope.

Dook wrote:

Am I stuck on the RTG idea?  Yes, to power the first Mars habitat and, once established, to power the buried habitat and greenhouse.  At some point in the future a larger nuclear reactor like you suggested would be good, maybe in 100 years.

A GPHS-RTG nominally generates 4.4kWt and .3kWe and weighs 57kg.  SAFE-400 produces 100kWe and the core only weighs 512kg.  If you added the radiator structure and some shielding to permit humans to approach to within perhaps 100M before entering the exclusion zone, it might weigh 2t to 3t.  If you only added the radiators, it would weigh around 1t.  Is that too much of a hit on your mass budget for reliable power and lots of it?

Dook wrote:

You never promised sending RTG's to Mars?  It doesn't really matter whether you did or not, does it?

Umm, yeah what I actually stated really does matter.

Dook wrote:

I know little to nothing about radiation exposure?  Never been irradiated.  How about you?  Seems you're getting upset.  You know that means you're losing the argument, right?

You know you actually have to critique what the other person argued in order to win an argument, right?

If I say "The sky is not blue" and you come back with "Roses are red", that's called a non-sequitur.

Dook wrote:

You don't like my Long Range Rover idea?  Oh boo hoo, and I sooo much wanted you to like it.  Wait, who are you again?  Are you someone important?  Let's see, is NASA asking enlisted swabbies how to go to Mars?  Nope.  Is Elon Musk?  Nope.

It has nothing to do with what I like or don't like, Dook.  You proposed a design that put really heavy, low-capacity batteries that can leak hydrogen and short circuit in a potentially explosive atmosphere inside a pressurized crew compartment.

Why do you think ISS has the batteries mounted on the truss?  The effects of fires, never mind explosions, typically ranges from highly destructive to lethal in space.  I'm trying to help you design a rover that won't endanger the crew.  This is an example of actual peer review, in contrast to many of the statements you've made that you think are critiques that happen to be your own assertions about things I've never actually proposed.

Dook wrote:

Mr. Musk didn't propose using the heavy Falcon to create a colony on Mars?  Then why does the website say that it will put 29 tons on Mars if they're not going to use it to land things on Mars?

Mr Musk is proposing using ITS to colonize Mars and that's a good thing because Falcon Heavy delivers far too little payload for a realistic number of launches.

Dook wrote:

Elon Musk has built one of the tanks and fired an engine?  That's fantastic, so we better start getting the 1 million people lined up now or do they have a few years to pack?

Mr. Musk hasn't actually launched a Falcon Heavy yet, has he?  Should we bother kicking the tires on Mars Direct until that happens?

Dook wrote:

Elon Musk doesn't have any investors?  So he's going to send people to Mars for free?  Probably not, each person who goes will have to pay for the flight.  Those people are "investors".  If a flight fails and bodies are spread out all over the planet or dying of oxygen depravation on Mars it's going to become tougher to get those "investors".  Also, SpaceX has contracts with NASA to deliver things to the ISS.  If Elon Musk gets too crazy NASA will end it's contract.

You're mostly right about this.  If Mr. Musk did something too crazy, NASA could decide to cancel his contracts.  Thankfully, SpaceX is not limited to NASA contracts and since they haven't already cancelled his contracts, I guess they don't find his proposals all that crazy.  The people who work at NASA generally support space exploration and even space colonization.

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#84 2016-10-06 14:54:07

Mark Friedenbach
Member
From: Mountain View, CA
Registered: 2003-01-31
Posts: 325

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

GW Johnson wrote:

Intellectual property is currently the easiest (and cheapest) thing to transmit across interplanetary distances.

Intellectual property doesn't require being on Mars.

EDIT: Also, to the rest of the thread: don't feed the trolls.

Last edited by Mark Friedenbach (2016-10-06 14:57:28)

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#85 2016-10-06 15:37:00

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Antius wrote:
Dook wrote:
Terraformer wrote:

Ye gods, what did you think people were saying? Have you even been bothering to read our posts?

Have I read your posts?  You mean the posts about how to make ceramic bowls on Mars so we don't have to fly in a box of plastic ones?

Are those the posts you're wondering about?

Yes.  Small pieces of the puzzle.  The fact is that nobody knows straight off how we will go about manufacturing every product that we need on the surface of Mars.  None of us has the time to work all that out.  This site is basically a hobby for bored engineers, most of them with day jobs and family.  The fact that we do not have answers straight away does not mean they don't exist.  It means that none of us can afford the time for industrial design projects.

The fact remains that with CAD, CNC machines and 3D printers, we can potentially build up a sizable manufacturing capability on Mars fairly quickly.  With a small variety of raw materials from local sources, most of the components for base building can be manufactured locally from day 1.

As I have said before, the number 1 limitation on the rate of population increase for a Mars colony will be finding meaningful exports that can be sent back to Earth to pay for what is needed by the base.  Without that, any talk of a base with permanent population of more than 100 is cloud cuckoo land.  On the other hand, find something that can make big bucks Earthside and getting a million people to Mars is not unrealistic, because big companies will fund emigration to build the labour force they need.  In just a couple of hundred years, the US population swelled from zero to 300million.  In the same time frame, the population of Greenland went from almost zero to...almost zero.  The difference?  The US had resources that could be exported for profits and could be used to build industries that make products that sell for even more profit.  Our ability to create a Martian civilisation depends upon replicating this model.  If we can, then the difficulties of surviving and prospering on a barren planet will be overcome.  If we can't, then no amount of innovation will help build a Mars colony beyond a handful of people.

We'll manufacture things the same was as we do on the Earth but that's not going to be for a very long time. 

I don't get why some of you are in such an incredible hurry to do this.  I want to see it too but we're talking about something that is very dangerous.  There is a lot of risk as it is. 

You guys still have your cart before the horse.  Computer Aided Drafting doesn't build you anything.  We don't need CAD on Mars.  We have designs already done for most things.  Colonists on Mars are not going to need or want some new Martian style chairs or some new Martian style clothes or Martian style buildings.  The designs we already have are good enough.  In 500 years are Martians going to have their own styles compared to the Earth?  Sure, but that's way, way, way in the future.       

Most of the components for base building can be manufactured locally from day 1?  I disagree but you're thinking SpaceX is going to get this 1 million pound to Mars rocket going.  I don't see it ever flying.  The heavy Falcon should fly but that's only 29 tons to Mars. 

I also don't agree about Mars exports paying for increased colonization.  You're talking about space travel.  What could colonists on Mars possibly make that would be cheaper or better than we can make on the Earth?  Nothing.  There will be some market for things from Mars just because they are from Mars, maybe some works of art, sculptures from Martian regolith, or whatever. 

A colony on Mars shouldn't send anything back to the Earth because to do that you have to get hydrogen delivered from the Earth to Mars and then break it down into rocket fuel.  There's no way that cycle can be economically competitive.

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#86 2016-10-06 15:39:16

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

GW Johnson wrote:

Please see what I posted in the "Musk's Plans for Mars" thread,  post #180 dated 10-6-16.  It specifically applies to this thread as well. 

Looking solely at mineral extraction is the wrong model for planning colonization.  Producing and exporting intermediate or finished products from local resources is the right model. 

Intellectual property is currently the easiest (and cheapest) thing to transmit across interplanetary distances. 

GW

GW, do you think that SpaceX's Interplanetary Transport rocket will be able to deliver 1 million pounds to Mars?

I'm okay with the heavy Falcon, the ITS seems impossible.

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#87 2016-10-06 15:50:38

Terraformer
Member
From: Ceres
Registered: 2007-08-27
Posts: 3,821
Website

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

A colony on Mars shouldn't send anything back to the Earth because to do that you have to get hydrogen delivered from the Earth to Mars and then break it down into rocket fuel.  There's no way that cycle can be economically competitive.

...


Because Mars has no hydrogen of it's own. I guess.


...


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#88 2016-10-06 16:19:22

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

kbd512 wrote:
Dook wrote:

Mars actually is extremely dry in most places.  Ice is not water and the ice on Mars is mixed with frozen CO2.

Most places is not every place.  There's a difference between something that's generally true and universally true.  However, MRO says you're wrong and once again, we're going with actual data from NASA over Dook's say-so.

Ice is not water?  They must have taught science class a bit differently where you went to school.

Dook wrote:

RTG's don't require any more shielding?  I didn't say they did, what I said was that they need to be moved away from the base.  That's why I asked what kind of reactor that you were talking about because it seemed as if you wanted to use heat from it to heat the Mars surface and RTG's do not provide heat to an external place.

Ah, what the hell.  I find your responses amusing and ignorant enough that I'll attempt to educate you one more time.

A RTG is not a radiation hazard to humans in close proximity wearing T-shirts and jeans, never mind space suits.  There's no reason to move it away from the base.  It poses no radiation hazard to the astronauts living and working in close proximity to the device.  Even if you opened it up and dumped the fuel out on the ground, you'd have to do something ridiculously stupid like try to pick up the Pu pellets off the ground with your hands to suffer any radiation exposure greater than the background radiation exposure you're constantly receiving while standing on the surface of the planet.

NASA engineers stand right next to a RTG without issue on a routine basis when they're working on those devices.  The only special clothing worn is intended to prevent cuts or thermal burns and to prevent biological contamination of the RTG.

A RTG can't be turned on or off like a fission reactor because it's not designed as a reactor.  RTG's contain decaying radioactive isotopes that generate a lot of heat as a result of the decay of the radioactive isotope and that heat is used to generate electricity using a thermocouple.  Thus the RTG is a radioactive decay-powered thermocouple.  Fission reactors or "nuclear reactors" generate heat by splitting atoms.  There is no comparison, none whatsoever, between the radiation that fissioning Pu generates and the radiation generated through decay of the Pu-238 isotope.

Dook wrote:

Am I stuck on the RTG idea?  Yes, to power the first Mars habitat and, once established, to power the buried habitat and greenhouse.  At some point in the future a larger nuclear reactor like you suggested would be good, maybe in 100 years.

A GPHS-RTG nominally generates 4.4kWt and .3kWe and weighs 57kg.  SAFE-400 produces 100kWe and the core only weighs 512kg.  If you added the radiator structure and some shielding to permit humans to approach to within perhaps 100M before entering the exclusion zone, it might weigh 2t to 3t.  If you only added the radiators, it would weigh around 1t.  Is that too much of a hit on your mass budget for reliable power and lots of it?

Dook wrote:

You never promised sending RTG's to Mars?  It doesn't really matter whether you did or not, does it?

Umm, yeah what I actually stated really does matter.

Dook wrote:

I know little to nothing about radiation exposure?  Never been irradiated.  How about you?  Seems you're getting upset.  You know that means you're losing the argument, right?

You know you actually have to critique what the other person argued in order to win an argument, right?

If I say "The sky is not blue" and you come back with "Roses are red", that's called a non-sequitur.

Dook wrote:

You don't like my Long Range Rover idea?  Oh boo hoo, and I sooo much wanted you to like it.  Wait, who are you again?  Are you someone important?  Let's see, is NASA asking enlisted swabbies how to go to Mars?  Nope.  Is Elon Musk?  Nope.

It has nothing to do with what I like or don't like, Dook.  You proposed a design that put really heavy, low-capacity batteries that can leak hydrogen and short circuit in a potentially explosive atmosphere inside a pressurized crew compartment.

Why do you think ISS has the batteries mounted on the truss?  The effects of fires, never mind explosions, typically ranges from highly destructive to lethal in space.  I'm trying to help you design a rover that won't endanger the crew.  This is an example of actual peer review, in contrast to many of the statements you've made that you think are critiques that happen to be your own assertions about things I've never actually proposed.

Dook wrote:

Mr. Musk didn't propose using the heavy Falcon to create a colony on Mars?  Then why does the website say that it will put 29 tons on Mars if they're not going to use it to land things on Mars?

Mr Musk is proposing using ITS to colonize Mars and that's a good thing because Falcon Heavy delivers far too little payload for a realistic number of launches.

Dook wrote:

Elon Musk has built one of the tanks and fired an engine?  That's fantastic, so we better start getting the 1 million people lined up now or do they have a few years to pack?

Mr. Musk hasn't actually launched a Falcon Heavy yet, has he?  Should we bother kicking the tires on Mars Direct until that happens?

Dook wrote:

Elon Musk doesn't have any investors?  So he's going to send people to Mars for free?  Probably not, each person who goes will have to pay for the flight.  Those people are "investors".  If a flight fails and bodies are spread out all over the planet or dying of oxygen depravation on Mars it's going to become tougher to get those "investors".  Also, SpaceX has contracts with NASA to deliver things to the ISS.  If Elon Musk gets too crazy NASA will end it's contract.

You're mostly right about this.  If Mr. Musk did something too crazy, NASA could decide to cancel his contracts.  Thankfully, SpaceX is not limited to NASA contracts and since they haven't already cancelled his contracts, I guess they don't find his proposals all that crazy.  The people who work at NASA generally support space exploration and even space colonization.


Ice is not water.  Water is not ice, that's why we have different words to describe them.  That ice that you are calling water is mixed with frozen carbon dioxide.  You need to be careful how much of it you bring inside your habitat or rover.  I guess the way to do it would be to take the ice mixed with frozen CO2 and put it inside a vented container that has a heater on it to warm and vent the CO2 out leaving behind the water.

There is no radiation hazard posed by RTG reactors?  Then you can put one inside your habitat and let it warm the hab.  But you're not going to do that, are you?  Hmm, I wonder why?

Is 1 ton too heavy to have a SAFE reactor?  Zubrin's Mars Direct component estimate alloted 1 ton for electricity, although I think he meant solar panels and an RTG which is what we should go with to start. 

What you were stating does matter?  No, it doesn't.  You're not important to anyone but yourself.  Elon Musk isn't checking with you to see what you think. 

I have to criticize argued in order to win?  You think you are in charge here?  You're not.  Try again, come on, give me another order.  What if I don't follow it?  Whatcha' gonna do?  Smoke more cigarettes?

Batteries don't "leak" hydrogen, they vent hydrogen.  So, you propose not using batteries in the rover?  You know there is a thread for that topic and it's not this one?

You're trying to help me?  No, you don't have enough power in your occupationj or at home so you come here to try and act like you're in charge.  You want to feel smart because at work you're a gopher, "Hey you, go for this, go for that".  Either way you're never going to be in charge of anything important, except stripping and waxing the floors.   

Mr. Musk is proposing using ITS to put equipment and people on Mars?  I'll believe it when I see it. 

Musk hasn't launched a heavy Falcon yet?  And NASA hasn't launched it's SLS either.  There's no hurry.  We'll get there when we get there.

Offline

#89 2016-10-06 16:25:48

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Terraformer wrote:

A colony on Mars shouldn't send anything back to the Earth because to do that you have to get hydrogen delivered from the Earth to Mars and then break it down into rocket fuel.  There's no way that cycle can be economically competitive.

...


Because Mars has no hydrogen of it's own. I guess.


...

Sure it does but it's tied up with oxygen. 

Water is too important on Mars as it is.  That's like taking gold and changing it into silver so you can then sell it.

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#90 2016-10-06 17:41:53

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,438

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Dook wrote:

Ice is not water.  Water is not ice, that's why we have different words to describe them.  That ice that you are calling water is mixed with frozen carbon dioxide.  You need to be careful how much of it you bring inside your habitat or rover.  I guess the way to do it would be to take the ice mixed with frozen CO2 and put it inside a vented container that has a heater on it to warm and vent the CO2 out leaving behind the water.

The Atlantic Ocean and Pacific Ocean are two different names that both still describe two large bodies of sea water.

BTW, you need the CO2 and the water, so if you can collect both at the same time, that's a bonus.  MOXIE needs that CO2 to make oxygen.

Dook wrote:

There is no radiation hazard posed by RTG reactors?  Then you can put one inside your habitat and let it warm the hab.  But you're not going to do that, are you?  Hmm, I wonder why?

Unless you open up the RTG, there's very little danger from radiation.  Even then, it's nowhere near as radioactive as an operating reactor.

Check out this super-radioactive RTG here:

RTG_radiation_measurement.jpg

It's so radioactive that a woman is standing next to it a T-shirt and jeans.  Maybe it's defective.  Maybe NASA just wasted our tax money on something that only looks like a RTG.  Maybe it's all part of a vast conspiracy of people who collaborated to make Dook look like Chicken Little on the internet.  Or maybe he just did that to himself.

If getting rid of the excess heat was not issue and there were no flammable substances in contact with the RTG casing, we could put a RTG in the habitat to stay warm.  If repurposing a RTG for heating a colony, it'd probably be a good idea to redesign the casing to maximize the heat you could transfer using a small a fan.

Dook wrote:

Is 1 ton too heavy to have a SAFE reactor?  Zubrin's Mars Direct component estimate alloted 1 ton for electricity, although I think he meant solar panels and an RTG which is what we should go with to start.

I'd rather have 100kWe, 24/7.  Dust storm or no dust storm, I wouldn't run out of power.

Dook wrote:

What you were stating does matter?  No, it doesn't.  You're not important to anyone but yourself.  Elon Musk isn't checking with you to see what you think.

You're right.  Mr. Musk doesn't think Dook is important, either.  Unlike Dook, Mr. Musk owns a rocket manufacturing company and has actually sent things other than his own ego into orbit.  All I'm doing is agreeing with Mr. Musk.

Dook wrote:

I have to criticize argued in order to win?  You think you are in charge here?  You're not.  Try again, come on, give me another order.  What if I don't follow it?  Whatcha' gonna do?  Smoke more cigarettes?

Feel free to criticize whatever you want.  Non-sequiturs won't make your criticisms valid, but if you like the noise feel free to bark at the moon.

Dook wrote:

Batteries don't "leak" hydrogen, they vent hydrogen.  So, you propose not using batteries in the rover?  You know there is a thread for that topic and it's not this one?

I have to criticize poor design choices in the thread you want me to use?  You think you are in charge here?  You're not.  Try again, come on, give me another order.  What if I don't follow it?  Whatcha' gonna do?  Whine and cry about me smoking more cigarettes again?

Dook wrote:

You're trying to help me?  No, you don't have enough power in your occupationj or at home so you come here to try and act like you're in charge.  You want to feel smart because at work you're a gopher, "Hey you, go for this, go for that".  Either way you're never going to be in charge of anything important, except stripping and waxing the floors.

I'm not sure anyone could help someone with your attitude, but I've certainly waxed all the ignorant criticisms and non-arguments you've failed to make.

Apart from being a professional troll and couch potato, what exactly do you do?

Dook wrote:

Mr. Musk is proposing using ITS to put equipment and people on Mars?  I'll believe it when I see it.

The same man who's company is building the rocket you're pinning Dr. Zubrin's Mars exploration dreams to is also directing his workers to work on ITS as time and resources permit.  It must be infuriating to you.

Dook wrote:

Musk hasn't launched a heavy Falcon yet?  And NASA hasn't launched it's SLS either.  There's no hurry.  We'll get there when we get there.

Unfortunately, no Falcon Heavy has left the pad yet.

Offline

#91 2016-10-06 18:55:22

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

kbd512 wrote:
Dook wrote:

Ice is not water.  Water is not ice, that's why we have different words to describe them.  That ice that you are calling water is mixed with frozen carbon dioxide.  You need to be careful how much of it you bring inside your habitat or rover.  I guess the way to do it would be to take the ice mixed with frozen CO2 and put it inside a vented container that has a heater on it to warm and vent the CO2 out leaving behind the water.

The Atlantic Ocean and Pacific Ocean are two different names that both still describe two large bodies of sea water.

BTW, you need the CO2 and the water, so if you can collect both at the same time, that's a bonus.  MOXIE needs that CO2 to make oxygen.

Dook wrote:

There is no radiation hazard posed by RTG reactors?  Then you can put one inside your habitat and let it warm the hab.  But you're not going to do that, are you?  Hmm, I wonder why?

Unless you open up the RTG, there's very little danger from radiation.  Even then, it's nowhere near as radioactive as an operating reactor.

Check out this super-radioactive RTG here:

RTG_radiation_measurement.jpg

It's so radioactive that a woman is standing next to it a T-shirt and jeans.  Maybe it's defective.  Maybe NASA just wasted our tax money on something that only looks like a RTG.  Maybe it's all part of a vast conspiracy of people who collaborated to make Dook look like Chicken Little on the internet.  Or maybe he just did that to himself.

If getting rid of the excess heat was not issue and there were no flammable substances in contact with the RTG casing, we could put a RTG in the habitat to stay warm.  If repurposing a RTG for heating a colony, it'd probably be a good idea to redesign the casing to maximize the heat you could transfer using a small a fan.

Dook wrote:

Is 1 ton too heavy to have a SAFE reactor?  Zubrin's Mars Direct component estimate alloted 1 ton for electricity, although I think he meant solar panels and an RTG which is what we should go with to start.

I'd rather have 100kWe, 24/7.  Dust storm or no dust storm, I wouldn't run out of power.

Dook wrote:

What you were stating does matter?  No, it doesn't.  You're not important to anyone but yourself.  Elon Musk isn't checking with you to see what you think.

You're right.  Mr. Musk doesn't think Dook is important, either.  Unlike Dook, Mr. Musk owns a rocket manufacturing company and has actually sent things other than his own ego into orbit.  All I'm doing is agreeing with Mr. Musk.

Dook wrote:

I have to criticize argued in order to win?  You think you are in charge here?  You're not.  Try again, come on, give me another order.  What if I don't follow it?  Whatcha' gonna do?  Smoke more cigarettes?

Feel free to criticize whatever you want.  Non-sequiturs won't make your criticisms valid, but if you like the noise feel free to bark at the moon.

Dook wrote:

Batteries don't "leak" hydrogen, they vent hydrogen.  So, you propose not using batteries in the rover?  You know there is a thread for that topic and it's not this one?

I have to criticize poor design choices in the thread you want me to use?  You think you are in charge here?  You're not.  Try again, come on, give me another order.  What if I don't follow it?  Whatcha' gonna do?  Whine and cry about me smoking more cigarettes again?

Dook wrote:

You're trying to help me?  No, you don't have enough power in your occupationj or at home so you come here to try and act like you're in charge.  You want to feel smart because at work you're a gopher, "Hey you, go for this, go for that".  Either way you're never going to be in charge of anything important, except stripping and waxing the floors.

I'm not sure anyone could help someone with your attitude, but I've certainly waxed all the ignorant criticisms and non-arguments you've failed to make.

Apart from being a professional troll and couch potato, what exactly do you do?

Dook wrote:

Mr. Musk is proposing using ITS to put equipment and people on Mars?  I'll believe it when I see it.

The same man who's company is building the rocket you're pinning Dr. Zubrin's Mars exploration dreams to is also directing his workers to work on ITS as time and resources permit.  It must be infuriating to you.

Dook wrote:

Musk hasn't launched a heavy Falcon yet?  And NASA hasn't launched it's SLS either.  There's no hurry.  We'll get there when we get there.

Unfortunately, no Falcon Heavy has left the pad yet.

The Atlantic and Pacific Ocean are two bodies of water?  And I'm the one supposedly using Strawman arguments? 

You don't need to collect frozen carbon dioxide.  The atmosphere of Mars is CO2.  You can get it anywhere you are so you don't have to transport it anywhere.  If we drive around Mars in a rover collecting ice to warm we're not going to be towing a MOXIE unit around with us.  The MOXIE will be back at the base doing it's thing. 

RTG's can be put inside the habitat for heating?  You might just be the only one who thinks that.

You'd rather have 100kwe nuclear reactor on Mars?  If we have almost unlimited delivery capability that would be fine but we won't.  An RTG will do fine.   

I don't just complain about smokers, I also get even.  Nothing better than being a non-smoker and owning stock in cigarette companies.  Can you step it up to two packs a day for me?  Come on, pleeeease, you can do it!  Everybody has to die from something. 

What exactly do I do?  Whatever I want, retired at 40 and paid for my house and land.  I wrote a check for it all.  I don't have to wear my name on my shirt.

I'm not pinning Mars Direct on SpaceX.  NASA is working on the SLS.  An SLS and a heavy Falcon working together can double Mars Direct landings on Mars.  It's not unfortunate that the heavy Falcon hasn't launched yet, it will go when it's ready.  Mars isn't going anywhere. 

If the ITS works it will be pretty amazing but that's a big "if".

Offline

#92 2016-10-06 22:12:12

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,438

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Dook wrote:

The Atlantic and Pacific Ocean are two bodies of water?  And I'm the one supposedly using Strawman arguments?

You've made some pretty nutty statements here, Dook.  Ice is not water, a RTG is a nuclear reactor, and so on.  I was only trying to take it to a level you might understand.  I could have one of my children draw a picture for you with some crayons if it helps.

Dook wrote:

You don't need to collect frozen carbon dioxide.  The atmosphere of Mars is CO2.  You can get it anywhere you are so you don't have to transport it anywhere.  If we drive around Mars in a rover collecting ice to warm we're not going to be towing a MOXIE unit around with us.  The MOXIE will be back at the base doing it's thing.

If you collect frozen CO2 with your ice, then you can feed more CO2 to MOXIE so you can make more O2.  You need not tow anything for this to work.  Simply scooping up a box full of regolith, close the lid, and use the heat from that RTG you like so much to sublimate the water and CO2.  There's nothing wrong with obtaining your oxygen and water at the same time.

Dook wrote:

RTG's can be put inside the habitat for heating?  You might just be the only one who thinks that.

Well, you can't snuggle with it and whisper sweet nothings into its radiator fins, but it's an alpha source (blocked entirely by the casing material or your own skin if there was no casing) and low energy X-ray source.  It's encased in Iridium, Graphite, Lead, and a few other materials.  If you're going to soak up more radiation, and more damaging radiation at that, just standing around on the surface of Mars, what major difference would a few low-energy X-rays?  You could set it next to your habitat or rover (radioactive hood ornament?) and you'd be no worse off than you'd be if it was 100M or more from where you were.

Dook wrote:

You'd rather have 100kwe nuclear reactor on Mars?  If we have almost unlimited delivery capability that would be fine but we won't.  An RTG will do fine.

It's a 1t item, 2t tops, and the power that a fission reactor can produce is exactly what an exploration team and certainly a colony needs.  It's a dusty planet that's 50% further from the Sun than we are and very cold.  Zubrin budgeted 1t for power generation.  I budgeted 2t.  Lots of things are possible with a 100kWe power source that are nonstarters with a few PV arrays and some batteries.  Dr. Zubrin advocated using a small fission reactor on Mars.

Dook wrote:

I don't just complain about smokers, I also get even.  Nothing better than being a non-smoker and owning stock in cigarette companies.  Can you step it up to two packs a day for me?  Come on, pleeeease, you can do it!  Everybody has to die from something.

What's it like putting money in the pockets of people who make products that you despise?  You're not hurting the tobacco makers at all and the smokers really don't care what you do.  Is trying to get even what you normally do when you feel impotent?

From the moment I was born, death was a certainty.  The same applies to you, too.  With your award-winning personality it may very well be an event that nobody remembers, but it's coming just the same.

Dook wrote:

What exactly do I do?  Whatever I want, retired at 40 and paid for my house and land.  I wrote a check for it all.  I don't have to wear my name on my shirt.

I see you're also obsessed with this name tag thing.  Did someone make you wear a name tag?  Did it hurt your feelings?  Do you need a safe space?

Dook wrote:

I'm not pinning Mars Direct on SpaceX.  NASA is working on the SLS.  An SLS and a heavy Falcon working together can double Mars Direct landings on Mars.  It's not unfortunate that the heavy Falcon hasn't launched yet, it will go when it's ready.  Mars isn't going anywhere.

Unfortunately, the next administration will likely cancel SLS.  President Obama already tried.  He should be given a medal for that, but somehow I think he only managed to incur the wrath of both parties and the defense contractors.  They're all too busy sucking NASA's funding dry.  We could easily do Mars Direct, which I am not at all opposed to, with the money that's been wasted on SLS and Orion.

Dook wrote:

If the ITS works it will be pretty amazing but that's a big "if".

It's a big rocket.  All "if's" are big.  It would probably already be flying if we'd funded that instead of SLS.  We could still debate using tinker toy rockets like F9 and F9H.  BTW, the payload sent to TMI, not delivered to the surface, is 13.6t by Mr. Musk's own statements.  I'm going to paraphrase Dr. Zubrin here.  13.6t is not 29t.  It's not.  With two launches and orbital assembly or electric propulsion, that could be substantially increased.

Offline

#93 2016-10-06 23:22:02

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

kbd512 wrote:
Dook wrote:

The Atlantic and Pacific Ocean are two bodies of water?  And I'm the one supposedly using Strawman arguments?

You've made some pretty nutty statements here, Dook.  Ice is not water, a RTG is a nuclear reactor, and so on.  I was only trying to take it to a level you might understand.  I could have one of my children draw a picture for you with some crayons if it helps.

Dook wrote:

You don't need to collect frozen carbon dioxide.  The atmosphere of Mars is CO2.  You can get it anywhere you are so you don't have to transport it anywhere.  If we drive around Mars in a rover collecting ice to warm we're not going to be towing a MOXIE unit around with us.  The MOXIE will be back at the base doing it's thing.

If you collect frozen CO2 with your ice, then you can feed more CO2 to MOXIE so you can make more O2.  You need not tow anything for this to work.  Simply scooping up a box full of regolith, close the lid, and use the heat from that RTG you like so much to sublimate the water and CO2.  There's nothing wrong with obtaining your oxygen and water at the same time.

Dook wrote:

RTG's can be put inside the habitat for heating?  You might just be the only one who thinks that.

Well, you can't snuggle with it and whisper sweet nothings into its radiator fins, but it's an alpha source (blocked entirely by the casing material or your own skin if there was no casing) and low energy X-ray source.  It's encased in Iridium, Graphite, Lead, and a few other materials.  If you're going to soak up more radiation, and more damaging radiation at that, just standing around on the surface of Mars, what major difference would a few low-energy X-rays?  You could set it next to your habitat or rover (radioactive hood ornament?) and you'd be no worse off than you'd be if it was 100M or more from where you were.

Dook wrote:

You'd rather have 100kwe nuclear reactor on Mars?  If we have almost unlimited delivery capability that would be fine but we won't.  An RTG will do fine.

It's a 1t item, 2t tops, and the power that a fission reactor can produce is exactly what an exploration team and certainly a colony needs.  It's a dusty planet that's 50% further from the Sun than we are and very cold.  Zubrin budgeted 1t for power generation.  I budgeted 2t.  Lots of things are possible with a 100kWe power source that are nonstarters with a few PV arrays and some batteries.  Dr. Zubrin advocated using a small fission reactor on Mars.

Dook wrote:

I don't just complain about smokers, I also get even.  Nothing better than being a non-smoker and owning stock in cigarette companies.  Can you step it up to two packs a day for me?  Come on, pleeeease, you can do it!  Everybody has to die from something.

What's it like putting money in the pockets of people who make products that you despise?  You're not hurting the tobacco makers at all and the smokers really don't care what you do.  Is trying to get even what you normally do when you feel impotent?

From the moment I was born, death was a certainty.  The same applies to you, too.  With your award-winning personality it may very well be an event that nobody remembers, but it's coming just the same.

Dook wrote:

What exactly do I do?  Whatever I want, retired at 40 and paid for my house and land.  I wrote a check for it all.  I don't have to wear my name on my shirt.

I see you're also obsessed with this name tag thing.  Did someone make you wear a name tag?  Did it hurt your feelings?  Do you need a safe space?

Dook wrote:

I'm not pinning Mars Direct on SpaceX.  NASA is working on the SLS.  An SLS and a heavy Falcon working together can double Mars Direct landings on Mars.  It's not unfortunate that the heavy Falcon hasn't launched yet, it will go when it's ready.  Mars isn't going anywhere.

Unfortunately, the next administration will likely cancel SLS.  President Obama already tried.  He should be given a medal for that, but somehow I think he only managed to incur the wrath of both parties and the defense contractors.  They're all too busy sucking NASA's funding dry.  We could easily do Mars Direct, which I am not at all opposed to, with the money that's been wasted on SLS and Orion.

Dook wrote:

If the ITS works it will be pretty amazing but that's a big "if".

It's a big rocket.  All "if's" are big.  It would probably already be flying if we'd funded that instead of SLS.  We could still debate using tinker toy rockets like F9 and F9H.  BTW, the payload sent to TMI, not delivered to the surface, is 13.6t by Mr. Musk's own statements.  I'm going to paraphrase Dr. Zubrin here.  13.6t is not 29t.  It's not.  With two launches and orbital assembly or electric propulsion, that could be substantially increased.

You don't feed CO2 into the MOXIE, it takes it in.  We're not going to go out and get CO2 because we don't have to.  CO2 is a gas atmosphere on Mars, it's also frozen hard in places.  Think of water, some places it's frozen, other places it's liquid, and some places it's evaporated.

You put the MOXIE somewhere, supply electricity, and it sucks in CO2 and makes oxygen.  There's no going to get more CO2.  It takes in what it's designed to take in.  What you're saying is like saying if we fire up a generator and somehow send more electricity into a laptop computer that already has house power it will somehow perform better, it won't.  It breaks if you do that. 

You can put the RTG where you want in your plans.  I can put it where I want in mine.

A fission reactor is what an exploration team and a colony needs?  The exploration comes first then comes the colony.  Zubrin's 1 ton for electricity weight budget fit within the Mars Direct plan which was to put humans on Mars.  His plan was infinitely better than NASA's 90 day plan.  Zubrin didn't expect the initial hab power supply to be the only source of power forever, in part of his book he describes settling Mars and terraforming it.  All Elon Musk has proposed is scaling that plan up. 

What's it like putting money into the pockets of people who make products that I despise?  It's called Capitalism or, you could also call it evolution.  I'm not worried about dying, I know what comes next, unlike you. 

As for the military name tag thing, I just don't get it, why can't the others learn your name?  And why have your last name on your shirt for others, who might be the enemy, to see?

Administrations change, you never know what's going to happen.  As for SLS, we need it for Mars Direct.  The Orion seems completely useless and an absolute waste. 

The ITS is not just a big rocket, it's beyond big.  I don't see it happening but we'll see. 

The payload is 13.6 tons to TMI?  The SpaceX heavy Falcon website says it delivers 29 tons (13 kg) to the surface of Mars.

Offline

#94 2016-10-07 08:08:58

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

It is big and completely reusable, it is the "Jumbo Jet" of rockets. It is expensive to build but then you get to use it multiple times, that helps pay for its cost, it has five times the lift capability of the Saturn V, and three times that capability when it is reused. reusability changes the equation on what is an economic size for these rockets, if they are throw away, you would want rockets that are medium-sized that can be rapidly manufactured and reliable with one shot one rocket, but with reusability, you can build larger. If this were the early days of aviation, I would say you were stuck on biplanes, and saying that it would not be economical to build a giant biplane that could carry 100 passengers.

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#95 2016-10-07 10:50:00

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,438

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Dook wrote:

You don't feed CO2 into the MOXIE, it takes it in.  We're not going to go out and get CO2 because we don't have to.  CO2 is a gas atmosphere on Mars, it's also frozen hard in places.  Think of water, some places it's frozen, other places it's liquid, and some places it's evaporated.

Frozen CO2 or dry ice, which is only a denser form of CO2, has more CO2 than Mars' atmosphere, which is only ~.087 psi.  If you can collect and store dry ice or liquid CO2, then you have more feedstock for your oxygen generator and it takes very little power to heat it in a sealed container to feed it to MOXIE.

Dook wrote:

You put the MOXIE somewhere, supply electricity, and it sucks in CO2 and makes oxygen.  There's no going to get more CO2.  It takes in what it's designed to take in.  What you're saying is like saying if we fire up a generator and somehow send more electricity into a laptop computer that already has house power it will somehow perform better, it won't.  It breaks if you do that.

If you've read the brief on the experiment, the SOXE (MOXIE) was designed to work two different ways because they're not sure how well the experiment will work with all the dust in Mars' atmosphere.  The backup mode of operation is to compress CO2 to 14.69 psi (average atmospheric pressure at sea level here on Earth) and feed it to MOXIE.  So no, it won't break the experiment.

If you haven't already read this PDF from NASA, it might be worth your time to review it:

The Mars Oxygen ISRU Experiment (MOXIE)

Regarding the computer analogy, within certain limitations, if you feed more power to the lithium ion battery in the laptop, the battery will recharge faster.  This principle is already in use here on Earth when it comes to recharging lithium ion electric vehicle batteries.

Dook wrote:

You can put the RTG where you want in your plans.  I can put it where I want in mine.

My concern is not where you put it.  MOXIE is intended to make ~22g of O2 per hour using 168W of input power.  The average person uses around 1kg of oxygen per day, so MOXIE is making 50% of what a human needs to survive (in terms of pure oxygen).  The RTG only outputs 300We.  If you add one more MOXIE unit, you've exceeded the power production capability of one RTG by 36We.

You have an exploration team of four people, right?

MOXIE alone will use 336We to replenish O2 requirements for one crew member (presuming no prolonged strenuous activity like an EVA), if you have a crew of four people, then you need 5 RTG's to assure power is available just to replenish O2.  During bad dust storms, NASA has shut Spirit and Opportunity down to conserve enough power to keep the rovers from completely draining their batteries.  We obviously can't shut down a manned base or rover without killing the crew, so we need some sort of backup that can minimally provide O2, scrub CO2, and reprocess water.  The water reprocessing could be halted during dust storms if we had sufficient grey water tank capacity or could replenish on Mars.

Dook wrote:

A fission reactor is what an exploration team and a colony needs?  The exploration comes first then comes the colony.  Zubrin's 1 ton for electricity weight budget fit within the Mars Direct plan which was to put humans on Mars.

Zubrin planned on using a 100kWe fission reactor (FSPS, SAFE-400, etc).  It's in every one of his presentations.  It's required to make the LOX/LCH4 on Mars to come back to Earth.  Mars Direct was not a suicide mission.  Dr. Zubrin's take on power requirements is no different than mine.  You only get half the solar irradiance in Mars orbit compared to Earth orbit.  Mars is 50% farther from the Sun.  Our PV panel tech was inadequate for Curiosity and Curiosity doesn't consume nearly as much power as an exploration team will.

Dook wrote:

His plan was infinitely better than NASA's 90 day plan.  Zubrin didn't expect the initial hab power supply to be the only source of power forever, in part of his book he describes settling Mars and terraforming it.  All Elon Musk has proposed is scaling that plan up.

Dr. Zubrin didn't expect to use solar panels and RTG's to meet all power requirements, either.  When he came up with Mars Direct, a fission reactor was the only realistic power source.  Unfortunately, PV and battery storage tech is not at a point where it's a replacement for a fission reactor.

Dook wrote:

What's it like putting money into the pockets of people who make products that I despise?  It's called Capitalism or, you could also call it evolution.  I'm not worried about dying, I know what comes next, unlike you.

Well, normally you're burnt or buried after you die.

Dook wrote:

As for the military name tag thing, I just don't get it, why can't the others learn your name?  And why have your last name on your shirt for others, who might be the enemy, to see?

If I introduced you to several hundred other people that you'd be working closely with, do you think you'd remember all of their names?

Dook wrote:

Administrations change, you never know what's going to happen.  As for SLS, we need it for Mars Direct.  The Orion seems completely useless and an absolute waste.

I don't have a problem with building a rocket with the lift capability of SLS, but it won't fly until 2018, there's no upper stage developed for it, there won't be any funding for an upper stage for another 10 years according to NASA, and thus the rocket will have been in development longer than the entire Saturn V program from initial development to decommissioning.

Dook wrote:

The ITS is not just a big rocket, it's beyond big.  I don't see it happening but we'll see.

If you want to deliver a big payload, you need a big rocket.

Dook wrote:

The payload is 13.6 tons to TMI?  The SpaceX heavy Falcon website says it delivers 29 tons (13 kg) to the surface of Mars.

If you can show me where SpaceX's website says that, please post the link.

So far as I know, the payload that Falcon Heavy can send to a Mars orbital injection or transfer trajectory is 30,000lbs (which is 15 US tons, not 29 tons) or 13,600kg or 13.6t (metric tons).  That means F9H can TMI 13.6t.  It does not say that it can deliver it to the surface of Mars.  I just checked it again.  It still says the same thing.  Using every new technology we have (electric propulsion from LEO to TMI, aerobraking with ADEPT, supersonic parachutes, and a last second rocket-assisted braking), it should be possible to soft land ~20t on Mars.  If F9H had propellant cross-feed and composite tanks, it would boost lift capability substantially.

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#96 2016-10-08 09:46:19

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Tom Kalbfus wrote:

It is big and completely reusable, it is the "Jumbo Jet" of rockets. It is expensive to build but then you get to use it multiple times, that helps pay for its cost, it has five times the lift capability of the Saturn V, and three times that capability when it is reused. reusability changes the equation on what is an economic size for these rockets, if they are throw away, you would want rockets that are medium-sized that can be rapidly manufactured and reliable with one shot one rocket, but with reusability, you can build larger. If this were the early days of aviation, I would say you were stuck on biplanes, and saying that it would not be economical to build a giant biplane that could carry 100 passengers.

I didn't say the rocket was not economical.  What I said was that Elon Musk has to be almost perfect or he will lose his customers and contracts with NASA.

Last edited by Dook (2016-10-08 10:22:31)

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#97 2016-10-08 10:19:29

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

kbd512 wrote:
Dook wrote:

You don't feed CO2 into the MOXIE, it takes it in.  We're not going to go out and get CO2 because we don't have to.  CO2 is a gas atmosphere on Mars, it's also frozen hard in places.  Think of water, some places it's frozen, other places it's liquid, and some places it's evaporated.

Frozen CO2 or dry ice, which is only a denser form of CO2, has more CO2 than Mars' atmosphere, which is only ~.087 psi.  If you can collect and store dry ice or liquid CO2, then you have more feedstock for your oxygen generator and it takes very little power to heat it in a sealed container to feed it to MOXIE.

Dook wrote:

You put the MOXIE somewhere, supply electricity, and it sucks in CO2 and makes oxygen.  There's no going to get more CO2.  It takes in what it's designed to take in.  What you're saying is like saying if we fire up a generator and somehow send more electricity into a laptop computer that already has house power it will somehow perform better, it won't.  It breaks if you do that.

If you've read the brief on the experiment, the SOXE (MOXIE) was designed to work two different ways because they're not sure how well the experiment will work with all the dust in Mars' atmosphere.  The backup mode of operation is to compress CO2 to 14.69 psi (average atmospheric pressure at sea level here on Earth) and feed it to MOXIE.  So no, it won't break the experiment.

If you haven't already read this PDF from NASA, it might be worth your time to review it:

The Mars Oxygen ISRU Experiment (MOXIE)

Regarding the computer analogy, within certain limitations, if you feed more power to the lithium ion battery in the laptop, the battery will recharge faster.  This principle is already in use here on Earth when it comes to recharging lithium ion electric vehicle batteries.

Dook wrote:

You can put the RTG where you want in your plans.  I can put it where I want in mine.

My concern is not where you put it.  MOXIE is intended to make ~22g of O2 per hour using 168W of input power.  The average person uses around 1kg of oxygen per day, so MOXIE is making 50% of what a human needs to survive (in terms of pure oxygen).  The RTG only outputs 300We.  If you add one more MOXIE unit, you've exceeded the power production capability of one RTG by 36We.

You have an exploration team of four people, right?

MOXIE alone will use 336We to replenish O2 requirements for one crew member (presuming no prolonged strenuous activity like an EVA), if you have a crew of four people, then you need 5 RTG's to assure power is available just to replenish O2.  During bad dust storms, NASA has shut Spirit and Opportunity down to conserve enough power to keep the rovers from completely draining their batteries.  We obviously can't shut down a manned base or rover without killing the crew, so we need some sort of backup that can minimally provide O2, scrub CO2, and reprocess water.  The water reprocessing could be halted during dust storms if we had sufficient grey water tank capacity or could replenish on Mars.

Dook wrote:

A fission reactor is what an exploration team and a colony needs?  The exploration comes first then comes the colony.  Zubrin's 1 ton for electricity weight budget fit within the Mars Direct plan which was to put humans on Mars.

Zubrin planned on using a 100kWe fission reactor (FSPS, SAFE-400, etc).  It's in every one of his presentations.  It's required to make the LOX/LCH4 on Mars to come back to Earth.  Mars Direct was not a suicide mission.  Dr. Zubrin's take on power requirements is no different than mine.  You only get half the solar irradiance in Mars orbit compared to Earth orbit.  Mars is 50% farther from the Sun.  Our PV panel tech was inadequate for Curiosity and Curiosity doesn't consume nearly as much power as an exploration team will.

Dook wrote:

His plan was infinitely better than NASA's 90 day plan.  Zubrin didn't expect the initial hab power supply to be the only source of power forever, in part of his book he describes settling Mars and terraforming it.  All Elon Musk has proposed is scaling that plan up.

Dr. Zubrin didn't expect to use solar panels and RTG's to meet all power requirements, either.  When he came up with Mars Direct, a fission reactor was the only realistic power source.  Unfortunately, PV and battery storage tech is not at a point where it's a replacement for a fission reactor.

Dook wrote:

What's it like putting money into the pockets of people who make products that I despise?  It's called Capitalism or, you could also call it evolution.  I'm not worried about dying, I know what comes next, unlike you.

Well, normally you're burnt or buried after you die.

Dook wrote:

As for the military name tag thing, I just don't get it, why can't the others learn your name?  And why have your last name on your shirt for others, who might be the enemy, to see?

If I introduced you to several hundred other people that you'd be working closely with, do you think you'd remember all of their names?

Dook wrote:

Administrations change, you never know what's going to happen.  As for SLS, we need it for Mars Direct.  The Orion seems completely useless and an absolute waste.

I don't have a problem with building a rocket with the lift capability of SLS, but it won't fly until 2018, there's no upper stage developed for it, there won't be any funding for an upper stage for another 10 years according to NASA, and thus the rocket will have been in development longer than the entire Saturn V program from initial development to decommissioning.

Dook wrote:

The ITS is not just a big rocket, it's beyond big.  I don't see it happening but we'll see.

If you want to deliver a big payload, you need a big rocket.

Dook wrote:

The payload is 13.6 tons to TMI?  The SpaceX heavy Falcon website says it delivers 29 tons (13 kg) to the surface of Mars.

If you can show me where SpaceX's website says that, please post the link.

So far as I know, the payload that Falcon Heavy can send to a Mars orbital injection or transfer trajectory is 30,000lbs (which is 15 US tons, not 29 tons) or 13,600kg or 13.6t (metric tons).  That means F9H can TMI 13.6t.  It does not say that it can deliver it to the surface of Mars.  I just checked it again.  It still says the same thing.  Using every new technology we have (electric propulsion from LEO to TMI, aerobraking with ADEPT, supersonic parachutes, and a last second rocket-assisted braking), it should be possible to soft land ~20t on Mars.  If F9H had propellant cross-feed and composite tanks, it would boost lift capability substantially.

So you're plan is to travel around Mars collecting dry ice, somehow store it, bring it back to base, then put it in some other device that warms it and then pressurizes the CO2 just so you can increase the inlet pressure to the MOXIE and get a little more production?  How much more production do you get for all this?  Since oxygen is critical you're going to need at least three MOXIE units anyway.

You're concern is that the MOXIE uses 168 watts so two of them would exceed one RTG's output?  I thought you were going to use the nuclear reactor? 

Would I have an exploration team of four?  Zubrin recommended a crew of four.  I think a crew of three would be better, one to stay back at the Mars Hab while the other two go out in the rover to explore.  And then when it's time to leave all three get in the Long Range Rover to go to the launch rocket.  My idea of exploration comes way before settlement while some of you want them both at the same time. 

If I worked with several hundred people would I remember their names?  Yes.  You don't look at people's name tags except when you're new, it doesn't take long until you recognize faces.  If a stranger comes in without a name tag then you just ask them their name. 

NASA has never had a good vision for it's own future.  Their small rovers on Mars are fine but they should have jumped all over Mars Direct when it was proposed and instead they backed off because it didn't use the Space Shuttle army and it wasn't their idea.         
If you want to deliver a big payload you need a big rocket?  Then why not just build a rocket twice the size of ITS? 

This web page shows the heavy Falcon:
http://www.spacex.com/falcon-heavy

Last edited by Dook (2016-10-08 10:21:40)

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#98 2016-10-08 11:46:38

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,464
Website

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

It does help to go straight to the source for good data,  doesn't it?  Falcon-Heavy as projected for the first several flights delivers 54.4 tons to LEO,  22.2 tons to GTO,  13.6 tons to Mars,  and 2.9 tons to Pluto.  I didn't see any talk about propellant cross-feed.  That's probably for growth later. 

There are some caveats.  "LEO" does not mean the ISS orbit,  it usually means around 300 km at 23 degrees,  out of Canaveral.  ISS is a bit more demanding,  which reduces deliverable payload slightly.  What "Mars" means is delivery to an interplanetary trajectory that,  if timed right,  puts you in the vicinity of Mars.  Decelerating into orbit about Mars,  or landing on Mars,  has to come out of that 13.6 tons. 

I haven't actually seen a weight statement on Spacex's website for its Dragon capsules.  But based on the earlier versions of Falcon 9,  I'd guess a loaded Dragon 1 cargo vehicle masses about a max of 10 tons.  Probably not a lot different for manned Dragon,  version 2,  for which they report 1200 kg propellant on board for the Super Draco thrusters. 

Nobody has any figures,  to the best of my knowledge,  for that third variant Red Dragon,  based off the manned version 2.  But based on Falcon-Heavy's capability to Mars,  I'd guess it at 10-12 tons.  The only things I ever saw quoted for Red Dragon deliverable cargo was 1-2 tons stowed inside in the early proposals,  and 2+,  one source 2-4,  tons,  in the latest proposals. 

To the best of my knowledge,  all three share exactly the same pressure shell.  Red Dragon as the same landing legs and Super Draco's as manned Dragon version 2.  They just strip out all the seats and life support gear,  and the back-up landing chutes,  for Red Dragon.  I suspect they add some cargo shelves or restraints of some kind,  and some extra guidance gear. 

A series of Red Dragon shots starting in 2018 is the "pathfinder" for Musk's big ship,  which he wants to start flying to Mars in 2022.  I presume he locates the site he wants with ground truth out of the Red Dragons.  He also says he wants to fly men to Mars starting in 2024 or 2025.  The date disparity makes me wonder whether the first 2 or 3 big-ship shots will be unmanned,  equipment-only cargo shots one-way,  at up to 100 tons each. 

Whatever that Sabatier-reactor propellant plant really is,  it needs to be big.  If the ship has no crew to bring home,  the propellant plant can stay in its belly.  There is some robotics involved,  as his slides from Guadalajara show inputs of Mars CO2 and water to his plant,  to create both methane and oxygen.  The "air" is with you no matter what.  The water is not. 

I've talked elsewhere on these forums about the impact site selection has upon ice mining.  A robot might be able to "frack" a massive deposit with steam down a single well to get the water.  Strip mining thin veins and lenses?  No way. 

There's lots of speculation to my interpretations,  but I think what he has in mind is not so very far from what I describe. 

I will say this:  Musk/Spacex seem quite willing to throw the "min thrown weight" box on mission design that everybody has used since 1960,  out the window and leave it in the dust.  I'd bet they also feel just as unconstrained by NASA's insistence on a "95% efficient life support system".  At least for their faster-than-min-energy Mars shots,  they're not worried about microgravity exposure. 

GCR radiation just isn't the bugaboo that it is still often made out to be.  It's rare and erratic large solar flare events that are the real risk.  They need to be thinking about that one.  I didn't see that in the Guadalajara slides. 

GW

Last edited by GW Johnson (2016-10-08 11:52:09)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#99 2016-10-08 14:11:35

Dook
Banned
From: USA
Registered: 2004-01-09
Posts: 1,409

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

SpaceX heavy Falcon

Falcon%20Heavy%20Capture.png

Last edited by Dook (2016-10-08 14:11:59)

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#100 2016-10-08 15:17:47

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

kbd512 wrote:
Dook wrote:

...

Dook wrote:

What's it like putting money into the pockets of people who make products that I despise?  It's called Capitalism or, you could also call it evolution.  I'm not worried about dying, I know what comes next, unlike you.

Well, normally you're burnt or buried after you die..

That is third person, bet you don't know what happens first person when you die, no one does! Knowledge and belief are not the same thing.

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