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#26 2018-05-31 07:57:06

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,855

Re: NASA's planning for Mars human missions - interesting stuff.

I've nothing against SEP development, except that diverting resources to it would delay the advent of Mars settlement.


Terraformer wrote:
louis wrote:

The BFR can is intended to deliver 150 tonnes to Mars.

There, fixed it for you.

How much would an SEP demonstration mission cost? I mean, one powerful (and cheap - no using xenon) enough to use for human missions, or at least mass cargo transport. A 1 tonne spacecraft, perhaps, done on a budget of a couple hundred million dollars as part of the discovery program? Send it


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#27 2018-05-31 12:32:40

Oldfart1939
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Registered: 2016-11-26
Posts: 2,218

Re: NASA's planning for Mars human missions - interesting stuff.

I'm not opposed to SEP research missions, but we best not wait around for their development. After all, Chris Columbus didn't wait for the Queen Mary before sailing westward. He used what was available at the time, and although it's "less elegant," it is what we should do NOW. And this is definitely unlike NASA, who has the unobtanium requirement inserted into the LOP-G plans.

Conceptually, the Baker-Zubrin plan of 1989 would have worked. In the interim, NASA has blown through enough spare change to have fully funded the budget priced Mars missions in Mars Direct. Flying the SS to construct the ISS, losing 14 astronauts in the process, has cost an unbelievable amount of money; estimates I've seen go as high as $80 Billion, but probably and realistically, $40 Billion. What would $40 Billion of TODAY'S dollars purchase from Space X? A LOT!

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#28 2018-05-31 12:37:49

Terraformer
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From: Logres
Registered: 2007-08-27
Posts: 3,362
Website

Re: NASA's planning for Mars human missions - interesting stuff.

Exactly. Why wait for the BFR, when we already have the Falcon Heavy?


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#29 2018-05-31 14:45:20

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,218

Re: NASA's planning for Mars human missions - interesting stuff.

You'll get no argument from me in that regard. I personally am of the opinion that Musk should NOT have cancelled the Red Dragon missions launched by Falcon Heavy. They would provide good practice and pioneering missions for the yet-to-fly BFR.

IMHO, there should be one FH Red Dragon launch in 2020 for proof of concept, followed by 3 in 2022, or possibly 6 in 2022. The 2022 mission(s) could conceivably be manned. Send plenty of food in 2 of the RD spacecraft. But, then getting back still remains a problem!

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#30 2018-05-31 15:07:06

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,855

Re: NASA's planning for Mars human missions - interesting stuff.

Agreed! And yes, there was a time for the Baker-Zubrin mission design...but that time has passed. In the last decades NASA has spent billions on Mars robot missions which have been interesting but which also could have been fed into a Mars human mission. There's never really been a shortage of resources, only a shortage of will.

Oldfart1939 wrote:

I'm not opposed to SEP research missions, but we best not wait around for their development. After all, Chris Columbus didn't wait for the Queen Mary before sailing westward. He used what was available at the time, and although it's "less elegant," it is what we should do NOW. And this is definitely unlike NASA, who has the unobtanium requirement inserted into the LOP-G plans.

Conceptually, the Baker-Zubrin plan of 1989 would have worked. In the interim, NASA has blown through enough spare change to have fully funded the budget priced Mars missions in Mars Direct. Flying the SS to construct the ISS, losing 14 astronauts in the process, has cost an unbelievable amount of money; estimates I've seen go as high as $80 Billion, but probably and realistically, $40 Billion. What would $40 Billion of TODAY'S dollars purchase from Space X? A LOT!


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#31 2018-05-31 18:17:42

kbd512
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Registered: 2015-01-02
Posts: 4,604

Re: NASA's planning for Mars human missions - interesting stuff.

All,

I do not intend to hold up any missions for lack of technological development, except for reliable environmental controls (life support, radiation mitigation, electrical power provisioning), adequate computers / software / navigational control (already taken care of using existing technology), and a realistic plan to bring everyone home (if humans don't do well in .38g or disaster strikes), if necessary.  Fundamentally, any plan to go to Mars and stay on Mars mandates the use of local resources and highly reliable and efficient enabling technologies.

Louis,

BFS Capabilities

We'll know what BFS can deliver to Mars the very first time it delivers something to Mars.  Until then, everyone is just speculating.  SpaceX has a habit of crashing a few rockets before it perfects the landing.  The first few BFS should simply attempt to deliver water.  If BFS lands successfully, then we'll start operations with 150t to 450t of water.  If not, then more practice is required.  Before any of that happens, it would be really great if we confirm where the best sources of easily accessible water are located using Falcon Heavy pathfinder missions since their plan requires Martian water to use BFS.

Efficient Concept of Operations

I say we land several of these BFS cargo ships on Mars and then use them for habitation, food / water / propellant storage, and cannibalize the engines and electronics for spare parts to maintain follow on BFS LMO-to-Mars-back-to-LMO transports operational so we don't need BFS to return anyone to Earth.  Imagine how much extra tonnage can be delivered if SEP cyclers deliver humans and cargo from Earth orbit to Mars orbit and we use the BFS variants for orbital transport to and from the surface of the planets.  The tank configuration can then be optimized for maximum delivered tonnage instead of the divergent Earth return requirement.

Super Heavy Lift Flight Heritage

Nobody has 70 years of knowledge of how to construct and operate super heavy lift launch vehicles.  The US flew Saturn V thirteen times between 1967 and 1973.  The Russians flew Energia twice between 1987 and 1988.  The Space Shuttle was technically a super heavy lift vehicle, if the orbiter is considered payload, but it was never designed as such.  All of those launch vehicles were obscenely expensive to design, test, and operate.  SLS is proving to be a costly engineering nightmare since nearly everything is new, from the engine software, to the design of the main tank, to the infrastructure support facilities and vehicles.  I'm sure SpaceX can do better with modern technology, but it has to be an order of magnitude better for its intended purpose.

SEP Dramatically Increases Delivered Tonnage

I did not mean to imply that SEP is mandatory for the initial missions.  It's true that LOX and LCH4 are cheap, but they're not free, and the rockets that deliver the stuff are definitely not cheap.  The BFS maintenance costs will easily eclipse propellant costs and Mr. Musk is pricing tickets based upon fuel and maintenance costs since the gas bill always has to be paid.  To reduce transportation costs and increase delivered tonnage, SEP and even propellant free propulsion for interplanetary transit will rapidly become mandatory.  Someone, no matter who that someone is, has to pay for all of this.

Artificial Gravity

4 months in microgravity followed by an absolute minimum of 4g worth of deceleration from that screaming interplanetary reentry velocity may prove problematic.  SEP would enable comparatively sedate entries from orbital velocity and increase delivered tonnage as a direct result of lower initial velocity upon de-orbit in LMO.  Soyuz is 4.5g and Space Shuttle was 3g.  Most of the astronauts couldn't walk for a day or so after they returned to Earth from ISS and they exercise every single day for 3 hours a day.  I guess the colonists could do that since they have plenty of time to kill in transit, but the exercise is not optional.  If they were in 1g for the entire transit using a SEP cycler with AG, then it doesn't matter if they get there a little sooner or a little later because we know unequivocally that they'd be fine.  This is not a reason to stall use of BFS to set up the infrastructure, but actual colonization with people who aren't trained astronauts?  Someone better think that through or people will die.

Advanced Thin Film Solar

I did find finally find one press release from Ascent Solar for the areal density of one variant of their 25 micron product since it's not listed on their website literature.  A press release indicated that they completed delivery of $300K worth of that product in April to a European customer.  According to the press release it's 330g/m^2.  I have no idea what coatings were applied, though.  It's supposedly for near-space applications.  I believe it's for Thales Alenia Aerospace's very high altitude long flight duration blimps in conjunction with the near-satellite work done for Airbus Defense, presuming I remember what I previously read about that endeavor correctly.

Terraformer,

Everyone missed my point because they seem to think I'm talking about holding up missions for new technologies to come to fruition.  I never stated that and I would never suggest that.  Mars colonization is a long term endeavor and the requirements for colonization versus exploration are different.  In exploration, we spend as much money as is required to achieve what we want.  In colonization, we spend the minimum amount required to achieve a specific result.  If we want to colonize Mars, then we're playing a different kind of game that values delivered tonnage per dollar spent above everything else.

NASA and others have conducted trade studies on the flight duration of a SEP mission at varying power levels.  At 600kW to 700kW, the total flight time looks exactly like the total flight time for a chemical powered rocket.  If you could get to Mars in 3 months using a lot more propellant, then you could also get there in 6 months with a lot more payload.  That was Dr. Zubrin's original point and I’m reiterating it.  You can to Mars in 3 to 4 months?  So what?  You can get there in 6 months with more payload.  If you're going to live there, would you rather get there 3 months sooner or with a lot more delivered tonnage?

Apart from Xenon, Argon is also a suitable propellant.  Argon is $5/kg and quite plentiful, whereas Xenon is $1,200/kg and NASA uses so much of it that the world’s Xenon manufacturing industry has to ensure they account for NASA's consumption.  Argon’s ionization energy is about 30% higher, so you need ~30% more power to produce a given level of thrust, but Argon is a lot cheaper and more plentiful than Xenon will ever be.  There's somewhere else in the solar system that happens to have a lot of Argon in its atmosphere.  I seem to recall that that planet was named Mars, it's atmosphere is 1.9% Argon, and use of BFS already mandates sucking up hundreds of tons of the Martian atmosphere to produce LOX.  Since the compressed atmosphere has to be separated anyway to remove everything else, why not collect the Argon while we're at it and send it back up to orbit aboard BFS so we can refuel the interplanetary transports?

Aerojet-Rocketdyne's X3 (Nested Hall Effect Thruster / NHT) SEP thruster will complete testing this year.  These NHT’s get tested with Xenon and Krypton, but Argon will also work and other less advanced HET’s designed by the same company have also been successfully tested with Argon.  It requires about 30% more power, but it still works.  Orbital ATK's MegaFlex technology has already completed developmental testing.  Orbital ATK is also working on a finalized design based upon the GeoStar satellite bus that carries the avionics and gas tanks (Xenon and Argon were both considered in the design of the tanks) for NASA.  The new NHT’s require a maximum of 200kWe to produce maximum thrust, but the strength of the design is that it can vary Isp and thrust using 7 tested configurations combining output from 1 to 3 of the nested channels and varying input power levels.  A trio of these things would produce orbit-to-orbit flight times between 6 months and 9 months.  I seem to recall that chemical rocket engines also produce flight times between 6 and 9 months on a minimum energy Hohmann transfer.  More engines, power, and gas can produce shorter flight durations, but why bother?

NASA has also tested of 200kWe to 1MWe Hydrogen fueled MPD thrusters, but these thrusters require higher power for maximum efficiency.  A trio of X3 thrusters will produce about 45 Newtons with 600kWe input power, or 75 Newtons with a quincunx arrangement of X3 thrusters and 1MWe of input power.  The MPD Thrusters would produce 100 to 200 Newtons with 1MWe of input power.  The use of higher voltages and currents produces a jet-like exhaust plume that dramatically alters the thrust achieved.  The MPD thrusters use Hydrogen as fuel and require a few tens of grams of Hydrogen per second to achieve maximum thrust.  Each X3 thruster weighs 227kg, although AJ thinks their flight model will weigh 100kg to 150kg.  For comparison purposes, an equivalent thrust output MPD thruster is something most adults pick up and carry in a backpack.  Incidentally, many MPD thrusters also get tested with Argon, Krypton, or Xenon.

Since we could realistically construct and deploy multi-hundred kW class solar arrays in the next few years, we could also produce flight times that match BFS using a fraction of the fuel and launches.  BFS will purportedly use a 200kWe solar array to provide electrical power in transit.

Ascent Solar's 25 micron thin film CIGS arrays were space flight proven by JAXA, the arrays are inexpensive compared to Orbital ATK's UltraFlex and MegaFlex products, and commercially available in quantities that can provide the required output levels.  I don't think SpaceX could afford the arrays they'd have to purchase from Orbital ATK.  Even if they could, I don't think the manufacturer has the capacity to produce arrays in the volume required since the products are hand-built and other paying customers are already in line in front of SpaceX.

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#32 2018-05-31 20:13:55

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,733
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Re: NASA's planning for Mars human missions - interesting stuff.

louis wrote:

The reference in the video to "within a decade" relates to Earth-to-Earth BFR transit.   You would have to build the spaceport infrastructure  to support Earth-to-Earth transit and navigate a variety of planning and safety assessment processes, so clearly that would add years to the project. I didn't hear her say building the BFR would take 10 years.  If she did, I'd be interested for you to give a time on the video where she said it.

TED Talks interview @ 7 minutes 18 seconds

Interviewer: You might be the person best placed to answer this question which has puzzled me. Which is to shed light on this strange unit of time called "Elon Time". For example last year I asked Elon, you know, when Tesla would autodrive across America, and he said "By last December". Which is definitely true if you take Elon time into account. So how, what's the conversion ratio between Elon time and real time?
Gwynne: You put me in a unique position, Chris. Thanks for that. There's no question that Elon is very aggressive on his timelines, but frankly that drives us to do things better and faster.
...
Gwynne: There is two really important realizations for that. First of all when Elon says something you have to pause, and not immediately blurt out "well that's impossible" or "There's no way we're going to do that. I don't know how to do that. So you zip it, and you think about it, and you find ways to get that done. And the other thing I realized... and it made my job satisfaction substantially harder. So I always thought my job was to take these ideas and kind of turn them into company goals, make them achievable, and kind of roll the company over from the steep slope, get it comfortable. And I noticed every time I felt like we were there, we were rolling over, people were getting comfortable, Elon would throw something out there, and all the sudden we're not comfortable. We're climbing that steep slope again. But once I realized that's his job, and my job is to get the company close to comfortable so he can push again, and put us back on that slope. Then I started liking my job a lot more. Instead of always being frustrated.
Interviewer: So if I estimated the conversion ratio of Elon time to real time is about 2X, am I a long way out there, or...
Gwynne: That's not terrible. And you said it, I didn't.

TED Talks interview @ 16 minutes 45 seconds

Interviewer: So you already believe that this is going to be deployed at some point in our amazing future. When?
Gwynne: Within a decade, for sure.
Interviewer: And this is Gwynne time, or Elon time?
Gwynne: That's Gwynne time. I'm sure Elon would want us to go faster.
Interviewer: That's...Ok...That's certainly amazing.
Gwynne: I'm personally invested in this one, 'cause I travel a lot and I do not love to travel. And I would love to get to see my customers in Riyadh, leave in the morning and be back in time to make dinner.
Interviewer: So within 10 years an economy price ticket, or like a thousand or couple thousand dollars per person to fly New York to Shanghai.
Gwynne: I think between economy and business. But you do it in an hour.
Interviewer: Um, well, that is definitely something. And meanwhile the other use of BFR is being developed to go a little bit further than Shanghai. Talk about this. You guys have actually developed quite a detailed sort of picture of how humans might fly to Mars and what that would look like.
[Gwynne narates the BFR Mars video]

Last edited by RobertDyck (2018-05-31 20:18:50)

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#33 2018-06-01 03:41:28

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,855

Re: NASA's planning for Mars human missions - interesting stuff.

Robert,

Nowhere in those lengthy quotes you give does she say anything that would justify your original claim that "Gwynne Shotwell said BFR would fly within 10 years from now.  Not 2022, in a decade from now.". The only reference to 10 years (a decade) as I accurately indicated was where she was discussing how soon an Earth-to-Earth transit system could be put in place. To be able to do that within 10 years would I think imply the BFR was built and flying much, much earlier in line with Musk's presentation.

I think your time to crow is 1st June 2019 if by then they haven't had a short hop test of the BFR.

Last edited by louis (2018-06-01 03:41:47)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#34 2018-06-01 03:53:38

RobertDyck
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From: Winnipeg, Canada
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Posts: 6,733
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Re: NASA's planning for Mars human missions - interesting stuff.

Then watch the whole video. I'm tired to doing other people's work. If you want the exact words, then you go find them. You. It's your job, now go. I put in the effort to transcribe large chunks of the video, she does say it will take 10 years, yes a decade from now.

I pissed off at my boss. He has a repeated pattern of sending me on jobs, but when I send a simple email to ask how to fill-in the paperwork, he has a panic attack. He can't handle a single paragraph. This is work, and he can't read. The firm that hired him likes my work, and my boss doesn't have any employees who can do what I do. Yet every single time it ends in a yelling session. This is the only job he can get because of his past record of convictions for dealing drugs. Talked to a firm yesterday, about a dozen employees, about providing them with I.T. support, and went to a job fair. I really REALLY need a better job.

Bottom line: you watch the whole video. You find the quote. You, not me, you. By the way, the video also said BFR will be used on Earth first, before going to Mars. Now you quote where that was said. You. If you can't find it, then you haven't done your job.

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#35 2018-06-01 05:47:18

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,855

Re: NASA's planning for Mars human missions - interesting stuff.

I don't believe the quote is there, so I don't have to find it! lol Anyway, as I said, if you are so sure you are right, you've only got another year to wait before you can say Musk was wrong and is already behind schedule. 

RobertDyck wrote:

Then watch the whole video. I'm tired to doing other people's work. If you want the exact words, then you go find them. You. It's your job, now go. I put in the effort to transcribe large chunks of the video, she does say it will take 10 years, yes a decade from now.

I pissed off at my boss. He has a repeated pattern of sending me on jobs, but when I send a simple email to ask how to fill-in the paperwork, he has a panic attack. He can't handle a single paragraph. This is work, and he can't read. The firm that hired him likes my work, and my boss doesn't have any employees who can do what I do. Yet every single time it ends in a yelling session. This is the only job he can get because of his past record of convictions for dealing drugs. Talked to a firm yesterday, about a dozen employees, about providing them with I.T. support, and went to a job fair. I really REALLY need a better job.

Bottom line: you watch the whole video. You find the quote. You, not me, you. By the way, the video also said BFR will be used on Earth first, before going to Mars. Now you quote where that was said. You. If you can't find it, then you haven't done your job.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#36 2018-06-01 14:00:50

kbd512
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Registered: 2015-01-02
Posts: 4,604

Re: NASA's planning for Mars human missions - interesting stuff.

All banter about who said what to whom notwithstanding, nobody else here has addressed the fact that to send a single BFS to Mars requires five launches.  The cost of flying the rocket is not dominated by the fuel costs, but a substantial amount of fuel and maintenance is required to send BFS to Mars.  The orbital tanking operations may proceed like clockwork, but 4 extra launches are required to send anything to Mars.

SpaceX's goal is $10M per BFR launch, so $100M to send 100 people to Mars since the humans and their cargo arrive on 2 separate BFS according to Mr. Musk's CONOPS.  That works out to a cost of $1M per person.  That's still solidly within the realm of the level of funding available to governments and the largest corporations.  No common person will go to Mars at that price point.  If that's the goal, then very few people and organizations will send anyone to Mars.  I proposed sending 1,000 people at a time using SEP cyclers and loading 1,000 people into BFS for immediate delivery to the cycler in LEO.  If just 2 BFS launches were required to support this sort of mission, then the ticket price is $20,000 for both the passengers and their consumables for the transit.  Most people in the western world can afford to buy a car, but very few people can afford to live in a million dollar house.  The fuel costs for Mr. Musk's CONOPS work out to $10M per mission, or 10% of the operational cost per mission, and notional maintenance works out to $2M, or 2% of the operational cost per mission.

If an aerospace vehicle is reusable, then operational costs are dominated by repayment of loans for the purchase of the vehicle for commercial activities.  After just 10 flights with 1,000 passengers per flight, BFS has already paid for itself.  After just 20 flights, the booster and ship are paid off and generating recurring revenue.  There are some initial infrastructure costs that may take several decades to pay off, but the reusable transports can pay for themselves rather quickly with enough paying passengers and the infrastructure required to support them.  Presumably, the boosters cost will also be subsidized by paying commercial customers who pay for satellites.

If someone devotes some serious effort and research money to that SharkFin Magnetic Sail that Craig Davidson proposed, then it may be possible to send 1,000 people to Mars aboard the BFS itself, no cycler required, with a single launch and without refueling, in a matter of days.  At that point, the ticket price drops to $10,000 and that's an expensive international vacation for a family of four.  Put another way, if a couple could afford to buy a mid-size SUV, then they can also afford to move to Mars with their two children to start a new life on the new world.

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#37 2018-06-01 14:30:57

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,855

Re: NASA's planning for Mars human missions - interesting stuff.

I don't think you've got it right about people travelling to Mars accompanied by a separate cargo flight. That's proposed for Mission One (in addition to the further 2 cargo flights launched 2 years earlier).  But I don't think it's part of Musk's vision for mass settlement. 

Once a Mars settlement is established, the need to import large amounts of cargo per capita will decline rapidly.  Any cargo coming in will effectively be paid for by cargo going back to Earth. 

Even if you were right about $1million per person with the BFS, which I don't accept, there would be no shortage of organisations happy to spend that amount in the name of research, national prestige, artistic endeavour, advertising and marketing.  Certainly nothing to stop the settlement growing to several thousand people. 

kbd512 wrote:

All banter about who said what to whom notwithstanding, nobody else here has addressed the fact that to send a single BFS to Mars requires five launches.  The cost of flying the rocket is not dominated by the fuel costs, but a substantial amount of fuel and maintenance is required to send BFS to Mars.  The orbital tanking operations may proceed like clockwork, but 4 extra launches are required to send anything to Mars.

SpaceX's goal is $10M per BFR launch, so $100M to send 100 people to Mars since the humans and their cargo arrive on 2 separate BFS according to Mr. Musk's CONOPS.  That works out to a cost of $1M per person.  That's still solidly within the realm of the level of funding available to governments and the largest corporations.  No common person will go to Mars at that price point.  If that's the goal, then very few people and organizations will send anyone to Mars.  I proposed sending 1,000 people at a time using SEP cyclers and loading 1,000 people into BFS for immediate delivery to the cycler in LEO.  If just 2 BFS launches were required to support this sort of mission, then the ticket price is $20,000 for both the passengers and their consumables for the transit.  Most people in the western world can afford to buy a car, but very few people can afford to live in a million dollar house.  The fuel costs for Mr. Musk's CONOPS work out to $10M per mission, or 10% of the operational cost per mission, and notional maintenance works out to $2M, or 2% of the operational cost per mission.

If an aerospace vehicle is reusable, then operational costs are dominated by repayment of loans for the purchase of the vehicle for commercial activities.  After just 10 flights with 1,000 passengers per flight, BFS has already paid for itself.  After just 20 flights, the booster and ship are paid off and generating recurring revenue.  There are some initial infrastructure costs that may take several decades to pay off, but the reusable transports can pay for themselves rather quickly with enough paying passengers and the infrastructure required to support them.  Presumably, the boosters cost will also be subsidized by paying commercial customers who pay for satellites.

If someone devotes some serious effort and research money to that SharkFin Magnetic Sail that Craig Davidson proposed, then it may be possible to send 1,000 people to Mars aboard the BFS itself, no cycler required, with a single launch and without refueling, in a matter of days.  At that point, the ticket price drops to $10,000 and that's an expensive international vacation for a family of four.  Put another way, if a couple could afford to buy a mid-size SUV, then they can also afford to move to Mars with their two children to start a new life on the new world.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#38 2018-06-01 15:21:03

kbd512
Administrator
Registered: 2015-01-02
Posts: 4,604

Re: NASA's planning for Mars human missions - interesting stuff.

Louis,

There's nothing at all on Mars that's ready to use and we're starting from scratch on a planet tens of millions of miles away from Earth.  One cargo flight per mission is 1,500t of cargo over the course of two decades.  That's not enough to construct a civilization on another world for thousands of people.  The only logical place I can see humans living is within subterranean tunnels.  A boring tool for Mars would have to weigh 150t or less to be practical.  The ISS weighs 945t, it's home to 6 people at most, and it requires constant resupply from Earth.  The Bigelow Aerospace BA2100 was designed to hold 16 people and it weighs 70t.  That's still not good enough.  1,500t would provide a permanent place to live 342 people at most, so pre-built habitats are not a viable solution for colonization.

Mr. Musk's own concept of operations say it's $1M per person.  Since we've never sent anyone to Mars, whether or not you believe there will be sponsors to send people there is irrelevant.  We'll only know that when the time comes.  At present, only governments spend millions of dollars to send people into space.  Since that came out of your personal god's mouth, why won't you accept the Gospel of Saint Musk?  What kind of Muskovite are you?

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#39 2018-06-01 16:25:09

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,218

Re: NASA's planning for Mars human missions - interesting stuff.

My greatest fear is that Elon may have bitten off more than he can personally (or SpaceX, in particular) financially chew. Earlier in this discussion, the concept of using something we have NOW, the Falcon Heavy, came up. I'm an enthusiastic supporter of that concept, since it requires very little work (in comparison to the BFR) to be brought forward to fruition. It can, and should be, used as a stepping stone to Mars. We've discussed the problem of landing accuracy and rough terrain, w/r to landing site selection. I am very interested in a Red Dragon vehicle (unmanned) with a good onboard camera system to make a highly detailed 360 degree panoramic study of where it has landed. It should have onboard a powerful transponder system for detailed surface position, geographically. A second Red Dragon should be flown in the same Hohmann Transfer window, identically equipped, but landed at a second site. Both vehicles would be well-supplied with long shelf life food--adequate for a 6 man team for 2 years. In the next Hohmann window, a second set of vehicles should be sent with water drilling and location equipment and a grader-frontloader for landing site improvement, as well as another pair of Red Dragon vehicles to possible landing sites 3 and 4. The point of all this is detailed landing site investigations. Maybe this doesn't seem important, but what it WILL accomplish is (1) refine the propulsive landing engineering, (2) investigate 4 landing zone possibilities, and (3) establish some prepositioned food and equipment for the first manned flights. I foresee the first manned flights departing Earth in 2026.

Last edited by Oldfart1939 (2018-06-01 16:25:44)

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#40 2018-06-01 16:46:39

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,855

Re: NASA's planning for Mars human missions - interesting stuff.

We'll have to agree to disagree on that...

I have researched these issues before.  Putting a PV panel manufacturing facility in place on Mars would be perfectly feasible. Once you have that covered, you no longer need to import PV panels from Earth. Really that's how you proceed. Build a few steel furnaces. No more need to import steel.  Go through the list.  Construction is obviously a big one: you need to create Mars brick manufacturing, Mars glass factories etc.

I think you could probably create a replica industrial and agricultural infrastructure for 2000 tonnes.  Space X plan to drop about 400 tonnes of cargo on Mission One alone.  So, I don't think this is an unachievable goal.

Of course if you are going to complicate things by wanting to bore tunnels  you will need to ship in more tonnage.

My recollection was that Musk was working towards to $250K per person, but you might be right.  I don't think Musk's mass settlement plans are credible in any case - but that has more to do with people management.  The number of people who would be suitable candidates for permanent relocation to Mars is quite small in my view in the short term. A lot of work needs to be done before Mars would be an attractive place for masses of humans to move to - you need to create Earth-like paraterraformed environments, resolve medical issues related to living in a 0.38G world, create a viable system of government, and ensure that procreation is successful.

kbd512 wrote:

Louis,

There's nothing at all on Mars that's ready to use and we're starting from scratch on a planet tens of millions of miles away from Earth.  One cargo flight per mission is 1,500t of cargo over the course of two decades.  That's not enough to construct a civilization on another world for thousands of people.  The only logical place I can see humans living is within subterranean tunnels.  A boring tool for Mars would have to weigh 150t or less to be practical.  The ISS weighs 945t, it's home to 6 people at most, and it requires constant resupply from Earth.  The Bigelow Aerospace BA2100 was designed to hold 16 people and it weighs 70t.  That's still not good enough.  1,500t would provide a permanent place to live 342 people at most, so pre-built habitats are not a viable solution for colonization.

Mr. Musk's own concept of operations say it's $1M per person.  Since we've never sent anyone to Mars, whether or not you believe there will be sponsors to send people there is irrelevant.  We'll only know that when the time comes.  At present, only governments spend millions of dollars to send people into space.  Since that came out of your personal god's mouth, why won't you accept the Gospel of Saint Musk?  What kind of Muskovite are you?

Last edited by louis (2018-06-01 16:47:35)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#41 2018-06-01 17:05:49

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,855

Re: NASA's planning for Mars human missions - interesting stuff.

Well there is nothing wrong with that sort of proposal - except that Musk has clearly abandoned that approach, having previously given it active consideration.

My view is that Musk's bold BFR proposal is a master-stroke, because it brings together seven (repeat SEVEN) major revenue streams (orbital tourism, lunar tourism, ISS supply, satellite launches, orbital internet, E2E transit and Mars settlement) in the development of a single rocket.  Any one of those revenue streams could generate billions of dollars and they will all be attractive to investors. I doubt BFR development will be held back by lack of money: only lack of facilities, lack of skilled operatives, the nature of the technical challenge and obstruction from vested interests are capable of slowing it down.

It's also my view - reinforced having read some of the papers that started out this thread - that the issues regarding landing zones have been overstated and, let's not forget, the first two BFSs to land on Mars are intended to be cargo ships, so no risk to humans.

Yes, there is a lot that Musk needs to work out but his approach has won out in the past. The company is only 16 years old and has achieved so much, starting from absolute scratch (NASA at least had a wealth of military operations to build on). 

I see the FH9 making its mark perhaps more in lunar tourism. Or it might just get written off once the BFR is in place.

Oldfart1939 wrote:

My greatest fear is that Elon may have bitten off more than he can personally (or SpaceX, in particular) financially chew. Earlier in this discussion, the concept of using something we have NOW, the Falcon Heavy, came up. I'm an enthusiastic supporter of that concept, since it requires very little work (in comparison to the BFR) to be brought forward to fruition. It can, and should be, used as a stepping stone to Mars. We've discussed the problem of landing accuracy and rough terrain, w/r to landing site selection. I am very interested in a Red Dragon vehicle (unmanned) with a good onboard camera system to make a highly detailed 360 degree panoramic study of where it has landed. It should have onboard a powerful transponder system for detailed surface position, geographically. A second Red Dragon should be flown in the same Hohmann Transfer window, identically equipped, but landed at a second site. Both vehicles would be well-supplied with long shelf life food--adequate for a 6 man team for 2 years. In the next Hohmann window, a second set of vehicles should be sent with water drilling and location equipment and a grader-frontloader for landing site improvement, as well as another pair of Red Dragon vehicles to possible landing sites 3 and 4. The point of all this is detailed landing site investigations. Maybe this doesn't seem important, but what it WILL accomplish is (1) refine the propulsive landing engineering, (2) investigate 4 landing zone possibilities, and (3) establish some prepositioned food and equipment for the first manned flights. I foresee the first manned flights departing Earth in 2026.

Last edited by louis (2018-06-01 18:44:33)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#42 2018-06-01 17:47:12

kbd512
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Registered: 2015-01-02
Posts: 4,604

Re: NASA's planning for Mars human missions - interesting stuff.

Oldfart1939,

I agree completely.  The rockets NASA needs are either available today or in the immediate future.  SpaceX intends to keep supporting Falcon 9 and Falcon Heavy for the near to mid term until BFR is thoroughly flight proven technology.  Everyone needs to light a fire to complete those ISRU missions prior to the push to colonize Mars.  Untold amounts of money will be saved by discovering what resources are available, where the best sources are located, and how we can best utilize what we find to support what we say we want to do.

I would very much like to see NASA do its part by supplying funding and scientists for the advanced life support, advanced solar power, battery / super capacitor / fuel cell storage, electric propulsion, and LOX/LCH4 technologies.  NASA should also supply trained crews who are suitable candidates for mission command staff, medical, and pilot duties for the exploration and colonization missions.

Louis,

No business can eat the costs of research, development, and manufacturing into perpetuity.  Sooner or later, there has to be a payoff where you at least break even.  It's fantastic that these multi-billionaires have finally realized there's nothing else that's of greater general utility to humanity, or even themselves, except leaving the cradle of life to take our place amongst the stars.  I applaud their vision, creativity, and unwavering determination to accomplish that objective, but all plans should be tempered with a healthy understanding of technological and engineering reality.

Now that you know what kind of power density the newest thin film CIGS photovoltaics are capable of, why would you first construct a manufacturing plant for that on Mars?  The total mass penalty is less than 1t per MWe, including the truss structures.  The robots involved might add another 1t or so.  That's insignificant.  I would think a battery or super capacitor plant and electrical conductor plant would be of far greater utility since these items are substantially more massive.

Apart from that, you rightly note that manufacture of steel, concrete, and glass are of utmost importance.  The electronics, solar panels, and construction robots are minor mass penalties, but materials for structures, food, water, and oxygen are impossible to import in quantities suitable to reconstruct civilization on another planet.  We have to make use of what we find there for those things.

1. Rocket Propellants

2. O2, N2, and H2O

3. Food and Textiles

4. Steel, Concrete, and Glass

5. Batteries, Super Capacitors, Fuel Cells, and Solar Panels

If we can make those five categories of things in orbit and on Mars, then humanity will flourish amongst the stars.

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#43 2018-06-01 18:11:13

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,218

Re: NASA's planning for Mars human missions - interesting stuff.

Louis-
I applaud your faith in the BFR, but based on SpaceX past performance, I remain somewhat skeptical of Musk's timelines. He cannot afford to simply wait for the availability of the BFR/BFS before attempting several of these pioneer missions. I don't believe SpaceX willfully abandoned Red Dragon, but were somewhat coerced by NASA to abandon the through-the-heat-shield landing legs based on the flimsiest conjecture that they were dangerous. It was NASA ultra risk aversion, that caused the initial Dragon manned vehicles to be parachute recovery systems. I'll be more optimistic once I hear reports of the BFS/BFR making grasshopper flights in Texas. But until that time, we need to use that which is immediately available--the Falcon Heavy and progressively heavier improved versions. To do things the way NASA wants them done is currently beyond the available fiscal resources of even Elon Musk OR Jeff Bezos.

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#44 2018-06-01 18:41:27

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,855

Re: NASA's planning for Mars human missions - interesting stuff.

kbd512 wrote:

Everyone needs to light a fire to complete those ISRU missions prior to the push to colonize Mars.  Untold amounts of money will be saved by discovering what resources are available, where the best sources are located, and how we can best utilize what we find to support what we say we want to do.

I think you are underestimating just how much information has already been gathered through Mars satellite surveys. Once we have a proper base on Mars human-directed detailed exploration can take place with rovers and rocket hoppers. It's much more effective that way - getting the humans on site rather than continuing with robot surveys, which will simply produced low def info.

kbd512 wrote:

I would very much like to see NASA do its part by supplying funding and scientists for the advanced life support, advanced solar power, battery / super capacitor / fuel cell storage, electric propulsion, and LOX/LCH4 technologies.  NASA should also supply trained crews who are suitable candidates for mission command staff, medical, and pilot duties for the exploration and colonization missions.

We'd all love to see NASA fully engaged but it is pointless hoping they ever will. The way the organisation is set up, it has become a snake pit of competing interests and "science" (as opposed to exploration, colonisation or economics) dominates the organisation.

kbd512 wrote:

No business can eat the costs of research, development, and manufacturing into perpetuity.  Sooner or later, there has to be a payoff where you at least break even.  It's fantastic that these multi-billionaires have finally realized there's nothing else that's of greater general utility to humanity, or even themselves, except leaving the cradle of life to take our place amongst the stars.  I applaud their vision, creativity, and unwavering determination to accomplish that objective, but all plans should be tempered with a healthy understanding of technological and engineering reality.

Plenty of businesses carry on being theoretically in debt.  NewsCorps was like that for decades...don't know if it still is but it could never pay off its debt yet used its position to prevent bankruptcy because the lenders didn't want it to fail.   National governments certainly continue in debt in perpetuity. There is hardly any state on Earth that isn't in debt...maybe Norway and Saudi Arabia are exceptions but every other state is up to their eyes in debt.

As previously indicated here, my view is that Mars settlement will be incredibly profitable.  We shall see.  But there is certainly no evidence of Space X going bust.

kbd512 wrote:

Now that you know what kind of power density the newest thin film CIGS photovoltaics are capable of, why would you first construct a manufacturing plant for that on Mars?  The total mass penalty is less than 1t per MWe, including the truss structures.  The robots involved might add another 1t or so.  That's insignificant.  I would think a battery or super capacitor plant and electrical conductor plant would be of far greater utility since these items are substantially more massive.

I don't think you would "first" construct a PV panel facility on Mars. But I think I would schedule that for the first 6-10 years because it is such a highly automated process that it could easily be transplanted to Mars. Mars has plentiful supplies of silicon that can be gathered by robot rovers.


kbd512 wrote:

Apart from that, you rightly note that manufacture of steel, concrete, and glass are of utmost importance.  The electronics, solar panels, and construction robots are minor mass penalties, but materials for structures, food, water, and oxygen are impossible to import in quantities suitable to reconstruct civilization on another planet.  We have to make use of what we find there for those things.

1. Rocket Propellants

2. O2, N2, and H2O

3. Food and Textiles

4. Steel, Concrete, and Glass

5. Batteries, Super Capacitors, Fuel Cells, and Solar Panels

If we can make those five categories of things in orbit and on Mars, then humanity will flourish amongst the stars.


I don't see how (with current technology) we make those things in orbit easily, but on Mars - yes, very definitely so.  The key is to transfer to Mars robots, machines and automated equipment that can extract materials from the surface, purify materials, create polymers, smelt and form metals, and then produce finished goods.

If at the end of the day 5% of the used mass on Mars has to be imported from Mars I doubt that will be a problem.  Here in the UK, the average person probably uses up about a tonne of material per annum (food, goods, industrial processes etc).  So for a community of 100,000 on Mars that would mean importing 5,000 tonnes per (Earth) annum. That would be about 33 BFSs per annum.  I think that is  perfectly feasible.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#45 2018-06-01 18:43:46

louis
Member
From: UK
Registered: 2008-03-24
Posts: 6,855

Re: NASA's planning for Mars human missions - interesting stuff.

I agree the hopper flights in Texas are the real first test...they are promised for the first half of 2019. If they are nowhere in sight in 2019 we will know the critics of Elon Time are right.  But if we see those flights in 2019 I would say it's game on.

Oldfart1939 wrote:

Louis-
I applaud your faith in the BFR, but based on SpaceX past performance, I remain somewhat skeptical of Musk's timelines. He cannot afford to simply wait for the availability of the BFR/BFS before attempting several of these pioneer missions. I don't believe SpaceX willfully abandoned Red Dragon, but were somewhat coerced by NASA to abandon the through-the-heat-shield landing legs based on the flimsiest conjecture that they were dangerous. It was NASA ultra risk aversion, that caused the initial Dragon manned vehicles to be parachute recovery systems. I'll be more optimistic once I hear reports of the BFS/BFR making grasshopper flights in Texas. But until that time, we need to use that which is immediately available--the Falcon Heavy and progressively heavier improved versions. To do things the way NASA wants them done is currently beyond the available fiscal resources of even Elon Musk OR Jeff Bezos.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#46 2018-06-02 09:04:06

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,024

Re: NASA's planning for Mars human missions - interesting stuff.

Back in the old days of the Red Colony louis, we had a topic which was dealing with the tonnage of the equipment needed to bring for the through put rate to creat the giant solar farms which would be needed to keep man's hungry energy need for expansion of presence on mars. The longer and larger the foot print of man is the greater the energy needs will be.

The hops are even with the a conparison of falcon to falcon 9 is about the scale for falcon 9 is to BFR first stage hops of which the first construction are only parts and not first stage in scaled down version of even at full size.

This was with falcon heavy February 21, 2017
https://www.entrepreneur.com/article/289558
Last fall, Musk said he anticipated that the first manned mission to the planet would commence in 2026 and land on Mars in 2027.

Progression of Space x flights
SpaceX-Progress.jpg

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#47 2018-06-02 09:35:22

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,024

Re: NASA's planning for Mars human missions - interesting stuff.

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#49 2018-06-02 16:12:52

kbd512
Administrator
Registered: 2015-01-02
Posts: 4,604

Re: NASA's planning for Mars human missions - interesting stuff.

Louis,

Everyone else's points are pretty simple:

1. We need explorers to go to the surface of Mars to confirm what our satellites tell us.  Ground truth is the only real truth.  There are no substitutes.  Period.

2. We already have a rocket that can send humans and cargo to Mars.  It's called Falcon Heavy.  It's not ideal, but it's good enough for government work.  The orbital tanking idea needs to be tested and refined before a pair of gigantic vehicles are orbited that mandate that the technology works correctly from the word "go".  That's an engineering reality exercise.  If some valve gets frozen in place or a docking clamp doesn't release, then it's best if that happens to a much cheaper scale test model.  It's a confirmation test.  Just do it.  In the interim, storable chemical propellants and SEP are good enough to send exploration missions to Mars.

3. We can concern ourselves with manufacturing propellant to send vehicles back to Earth from Mars after we conduct an experiment to determine how much water we can get from the regolith or buried glaciers.  If it turns out something about the atmospheric processor or water processor doesn't work as intended, then the time to find out about that would be before we gamble lives on that technology, not after.

SpaceNut,

We now have sufficiently power dense thin film solar cells to skip the use of fission reactors for daytime operations that require MW-class electrical power, but we still need batteries or super capacitors that have a similar improvement in performance over legacy technology.  There are some promising candidate technologies on both fronts, but as of yet, nothing has been commercialized.

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#50 2018-06-02 17:28:17

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,218

Re: NASA's planning for Mars human missions - interesting stuff.

If we stop to do a bit of bookkeeping on what's necessary for the first flights to Mars: (1) grasshopper flights of both booster stage and of the BFS Mars lander; (2) LEO launch and recovery of the BFS and the BFR booster stages. But then what? We need at least 2 more boosters and a couple fuel tankers, followed by: (1) demonstration of in-orbit refueling; (2) launch of a cargo freighter to Mars; (3) successful landing and robotics deployment.

All of these are simply starters. It says nothing about the necessary mars infrastructure facilitating return of the first experimental lander(s). That's an awful lot to (1) accomplish; (2) get it paid for with zero return from the expenditure of these funds.

Color me skeptical, not pessimistic.

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