Dr. Robert Zubrin - Mars Direct 2.0 - ISDC 2019

[@vahangood5999]

I have a feeling that this speech is going to have millions of views some day and be celebrated as one of the pivotal, history-making speeches. Great speech 👍 Dr. Zubrin and thank you for your endeavors!

[@Illisil]

He's been doing this same speech and using the same graphics since the 80's

[@sabretechv2]

How’s that theory workin out for ya lmao

[@nicosmind3]

Omg, yes to the tether tests. I just commented this the other day. Its info we should have had 20 years ago!!!

[@jshepard152]

Fifty years ago. There were plans to do it on Gemini.

[@CapinCooke]

Well Dr. Z... Thanks for your continued inspiration, motivation and outreach to bring the Mars dream home. Sure... lots of work to still do. But it IS all doable. Let’s do it! I loved your new CASE FOR SPACE book by the way. May your energy and aspirations regarding Mars never subside.

[@joewildturkey8253]

Zubrin's an absolute pitbull. His vision has not wavered one bit over the years. He's probably pissed a few people off at NASA but his light shines bright. He has much to offer and I hope he's still around we we put man on Mars

[@timblizzard4226]

I agree, but I actually don't like his argument here. I think SpaceX has the best architecture at the moment; just fly starship to mars.

[@BeKindToBirds]

​@@timblizzard4226SpaceX is going to kill the second space age.

[@3NFilms]

would also be really cool if Dr. Robert Zubrin spoke to Joe Rogan on his podcast

[@edwardethridge1483]

OMG! That would be the coolest interview ever!

[@3NFilms]

@@edwardethridge1483 YES! I wonder if Zubrin has read this novel which is excellent btw (Zubrin is quoted at the beginning of the book too): www.latimes.com/books/la-ca-jc-thin-air-20181109-story.html

[@parv_verma]

Yes, I would love that! Totally on board with this!

[@nicosmind3]

Dam right it would. Joe would love to have him on i bet too. He had Elon on and if anything Zubrin is even cooler, speaks with a passion etc. Would blow him and the audiance away!

[@alexanderjsdowding]

Facilitate it. Make it happen. Would love to watch that podcast.

[@zapfanzapfan]

Only downside I can see is if the Starship doesn't scale well. Some things need to be a certain size in order to work, some things don't work when they are too big, some things don't work when they are too small. Surface area scales as square, volume as cube.

[@palfers1]

480p? Really?

[@dazuk1969]

Zubrin rocks man....i know SpaceX has light the fuse that has enthused the world...but that all starts with Dr Zubrin....peace.

[@willymakeit5172]

This guy is prolific.

[@themagiceye6723]

He should be in charge of NASA

[@ResinRat2]

He is Focused AND Motivated !!

[@GlanderBrondurg]

@@themagiceye6723 Robert Zubrin has pissed off too many people at NASA to become administrator or deputy there. He would be a good person to put in charge of a Mars mission if a President had balls and wanted to make it happen ASAP. His sharp elbows and caustic contempt for those who get in his way would then be an asset.

[@themagiceye6723]

@@GlanderBrondurg Yep sadly you're absolutely right on the NASA admin post. Like your thinking re heading up the Mars mission. Although reality is probably similar... too many bridges (understandably) burned

[@MrGlenspace]

Zubrin very smart but also scatter brained. He would be a poor administrator. Plus not up to the President money spent. He can only request, but he wants to go to Mars. It is Congress that controls the money and I would hope everyone knows that already.

[@DanielOutdoors]

What is it with the bad live streaming quality, angles camera, and poor light? Like common guys I mention this last year... Problaby need to kearn other thing from SpaceX as well.. Apart from that Im not sure about the Mini- Starship thing. Think we need to focus more on the 100 passenger Starship more than anything. The Overview Effect is very important, and will regenerate more for SPace than anything else.

[@joe2mercs]

There is one important omission in Bob’s presentation and that is ‘cost’. Whilst capability assessment of mission profiles is useful I think Elon is much more convinced by proposals when accompanied by associated cost analysis. The advent of ‘full reusability’ is game changing in terms of reducing costs. Staging off LEO or TLI as Bob proposes still requires a landing vehicle to take payloads down to Mars surface. What is the cost of developing, testing and building this specific vehicle? Using Bob’s reference to the Normandy landings, if Storm Troopers are the cheapest and easiest units to train then your whole army will consequently be comprised of Storm Troopers. Likewise if the Starship is the cheapest and easiest vehicle to develop and operate then this will be the genetic vehicle that you use for every mission.

[@ron1613]

former Mars Society member looks forward to our visit to Mars

[@parthasarathyvenkatadri]

Well what would be the profitability of the mars missions ... If we setup a colony anywhere and it needs to be self sustaining it needs something that it can profit out off.

[@nathanwinkler4169]

Why can't a private organization use a Thorium fission reactor instead of Uranium for Mars Direct?

[@zapfanzapfan]

You still have to design it and build a test reactor somewhere. And you need Uranium or Plutonium to start it up.

[@hootis8]

Well in reality a molten salt reactor hasn't even been developed in the united states in the last 40 years and optimistic timelines would be 10 years from the day the research starts. Secondly the infrastructure for molten salt reactors while smaller than conventional LWR's is much larger than would ever be practical to bring on a spaceship. Some of the conceptual reactors are talking about a core loading th/u233 FLiBe of almost as much weight as a single starship could bring to mars forget about the actual reactor or buildings. There are many reasons for this, but sufficient to say TH/U233 reactors need to be a sufficient size, in experimental reactors you can vary the thermal output quite significantly giving the perception of a smaller reactor but the reactor and fuel itself is still about the same size. There are two feasible nuclear power plants that could be brought to mars, the primary would be a PU238(is that the right isotope) which would not be used in a reactor but would simply be a thermal energy use for a steam turbine or sterling engine. However the US ran out of PU238* with curiosity rover and while it started reproduction its at a very slow pace not sufficient for a large scale power plant. For political reasons there is not a single chance in hell a PU 100kw+ scale thermal source would be sent to mars for a private company. Secondly the only technically feasible reactor in real world production would be one of the US Navy's newest generation solid fuel LWR reactors. Mainly because they have recently started using highly enriched uranium (90%??) which is weapons grade but also gives a longer 30(??) year lifetime to the reactor without refueling. And the design is already minimized, and would probably work out of the box on mars, only the heat exchangers needing modification would probably would be very easy since the temperatures would be very favorable. Now again there is not a chance in hell the US navy would sell its highly classified and advanced nuclear reactors to a private company. Sidenote, it would theoretically be possible to build a highly enriched U235 molten salt reactor which could be quite small however you still run into the on line chemical processing and other issues that would increase the size. No company is designing a reactor like this because it would be uneconomical at best and would never be approved because of the use of weapons grade uranium. Now if you're still with me, every single hippy from San Fransisco to Brooklyn would have a shit fit if you told them you're going to launch a nuclear reactor into space and there's a .01% chance that the rocket fails to launch and then another 0.01% spreading nuclear waste material all across the east cost.

[@zapfanzapfan]

There is some development work happening with small reactors en.wikipedia.org/wiki/Kilopower for space applications but they are much to small to power fuel production on Mars. The one good thing with a reactor is that it's just Uranium. Before the reactor has been switched on there are no dangerous fission products so it's safer to launch than RTG:s with Pu-238. But to get that the hippies would have to respond to facts...

[@nathanwinkler4169]

@@hootis8 Thanks!

[@TraditionalAnglican]

hootis8 - NASA could “sponsor” the mission to Mars by sending 6-12 NASA astronauts on each of the first 3 or 4 missions. Although the US Navy would probably never sell one of its reactors to a private company, the Navy would allow NASA to “use” it on a “long-term (100 year) lease”, & NASA, the Navy & SpaceX could assemble the parts in LEO & insert them into NASA’s sponsored transport vehicle (Starship), & the parts could be assembled & the reactor turned on upon arrival to Mars. I think you’re mistaken about the feasibility of using Molten Salt Reactors. Prototype & Demonstration MSR’s were already running before the program was cancelled. Private companies (Power Companies) have been provided with enriched U-235 for 60+ years. According to the companies working on the technology now, very little U-235 is required to begin the process (Th-232 becomes fissile U-233 in the presence of a fission reaction), & MSR’s are pretty much “idiot proof”. www.world-nuclear.org/information-library/current-and-future-generation/molten-salt-reactors.aspx www.world-nuclear.org/information-library/current-and-future-generation/thorium.aspx en.m.wikipedia.org/wiki/Thorium_fuel_cycle#List_of_thorium-fueled_reactors en.m.wikipedia.org/wiki/Thorium-based_nuclear_power www.nanalyze.com/2015/10/6-nuclear-energy-companies-building-molten-salt-reactors/ www.reportlinker.com/p05589936/Molten-Salt-Reactors-Opportunity-and-Global-Markets.html www.scmp.com/news/china/science/article/2181396/how-china-hopes-play-leading-role-developing-next-generation en.m.wikipedia.org/wiki/India%27s_three-stage_nuclear_power_programme

[@stevemickler452]

Solar Thermal is an option that can be quickly developed at low cost unlike nuclear thermal. It is well suited to conjunction missions. In the early Sixties, Ehricke proposed a solar thermal rocket propelled vehicle that would use a thrust near Venus to reduce travel time and open up new launch windows. This means higher re-use and more frequent launch opportunities.

[@TraditionalAnglican]

Dr. Zubrin didn’t mention NTR - He discussed using chemical rockets, which, if you carried enough propellant, could get you to Mars in 1/3 of the time Solar Thermal Propulsion would require. His only mention of Nuclear Thermal Propulsion is as a System he would not use. NTP can be assembled in earth orbit, &, unlike Solar Thermal Propulsion, would actually get you to Mars in 2 months...

[@replica1052]

starship is worth more as habitat on mars than as a heavy lift vehicle on earth it is important for the mars crew to feel that they are plenty many large amounts of water surounded by reflectors will give plenty of O2 through photosyntesis and water locks will save air and pressurize the colony weather on mars; once it rains, fish can survive mars nature when everything comes from the sun, it makes sense to catch solar wind; pull cables from pole to pole slightly offset for the dynamo effect (water locks makes living easy)

[@replica1052]

the will to create is better

[@timblizzard4226]

With all due respect I think Zubrin’s reasoning here is actually quite poor. His arguments against flying a starship directly to the Martian surface are actually really weak, and they betray his mindset, which is stuck in the old paradigm. He only emphasises the advantages of his TLI/LOE plans, without really giving credence to their substantial problems. In any case, I don’t think he has truly come to grips which what Musk is doing with full reusability; the old rules simply won’t apply any more. These are his main points against the spaceX architecture, and they are all weak. Point 1: If you only use starship as a boost vehicle to LEO or TLI, you can use it on earth during the mars mission. Yes, this is true, any starship you sent to Mars will be gone for 2+ years. But how much of a cost is this really? Firstly the Mars injection window is not large, so even if you use that starship as a booster only, it won’t be doing anything to help the mars mission once the mars transfer window is gone. Additionally, the added benefit of having the starship available on earth while the mars mission is ongoing sounds amazing if you only envisage having one or two vehicles available; but given the economical materials utilised and the current rate of construction (4 prototypes already planned), by the late 2020s there may well be 30 or 40 cargo starships operational. So you’ve lost 3% ~ 5% of your total capability. It’s really not a big deal. And to achieve this 3% capability advantage, (one that could be covered by the construction of a single starship, which may not be very expensive once full rate production is achieved), you need to design a whole new architecture with a ‘mini starship’, mars cargo vehicle, disposable habitat, all of which need to be developed and tested. Because these new vehicles are not reusable, the testing process will be very time consuming. This really isn’t any advantage at all when you view the wider context. Point 2: Refuelling a starship will cost 342 kW of solar power, as opposed to his ‘mini-starship/earth return vehicle thing’, which will only need 81. Again, on paper, this is a large detriment, and Zubrin claims that this is “a large burden for a mars colony”. But is it really? Firstly, if NASA were to be involved, they are developing lightweight nuclear reactors for use in deep space, so one would be available in any collaboration. But, in any case, just how hard would it be to make a refuelling station with solar? Its hard to break down Zubrin’s numbers, he claims its 342kw for the ISRU plant to refuel starship. I’m not sure what he means here, as you should probably measure the energy requirements in kilowatt hours, not just kilowatts, because a smaller plant will simply take longer to refuel the Starship. But lets assume he means you need a 342 kW capacity solar farm to run an ISRU plant with enough capacity to refuel a single Starship in enough time to make the earth return window. So lets build a 400kW solar farm using only commercial panels available right now (no fancy lightweight stuff). A 300w panel typically used on a house weighs about 18kg/40lbs. Lightweight, flexible 300w panels weigh about 6kg/13lbs. So the average performance of a 6 kw solar system in Australia, a sunny place, is about 24kwh per day, but if we built on Mars, that would receive 40% the sunlight of earth, however there are barely any clouds in comparison. So, just to keep it simple, let’s just say that you get about 1/3 of the capacity of solar systems on earth (the reality is better than this). So to make our 400kw farm we would need about 4,000 solar panels, each rated at 300w. That is with a very healthy margin to account for dust storms. For LG, commercial panels, that’s 20 tons of solar panels, and if you use the flexible lightweight stuff which people use on RVs, its 6 tons. The payload of one starship is ONE HUNDRED AND FIFTY TONS!!!! If you use lightweight, commercial solar panels, which you can buy at an RV store, it will take just 4% of a single payload to mars, if you use the rigid, heavyweight panels, its 13%. Once this refuelling station is built, it is fixed there and can refuel many more missions. Any way you slice it, this simply isn’t a major burden for a mars colony, and certainly not one worth justifying the development of a whole new mission architecture including the R&D for a ‘mini-starship’, which is specialised and can only return people from mars. The additional payload of starship more than offsets the additional power requirements to refuel it. Pont 3: The cargo delivered to mars per launch is comparable when you include the refuelling flights for starship flights to mars. Who cares!!! We aren’t using the SLS to do this!!! With full reusability launch costs will not dominate the total mission costs. You are only paying for fuel and LOX costs $0.16 per litre. Methane isn’t that much more. This is evidence that Zubrin is stuck in the old paradigm: the R&D you spend developing a mars cargo vehicle (because mini starship can only put a tiny payload on Mars per transfer window, you probably need an expendable mars cargo vehicle which Zubrin just avoids here) and this mini-starship thing is not going to be more expensive than just paying the extra fuel costs to refuel a whole starship. Now for the reasons why just using starship is a much better idea: 1. Economy of scale: by simply utilising one, rapidly reusable vehicle as a booster, transfer vessel and lander, which can be mass produced, you massively reduce both R&D costs (which are spread across a large number of units) and production costs. Building multiple, specialised vehicles will dramatically increase R&D costs and have them spread across a fewer number of units, dramatically increasing total program cost. In aviation, you design a single aircraft (a Boeing 747) which can fly where you need it to, and you build hundreds of them. You don’t make a specific type of aircraft simply to fly from New York to Chicago and no further, even though technically that would be more efficient. That’s how you bring costs down and make a Martian colony real; mass production. 2. Payload to the Martian surface: Zubrin’s LEO architecture puts just 23 tons on the martian surface to support a year-long mission. That has to include power, a hab, life support, science and engineering equipment, comms, transport and food and water for a 6 person crew. Is that enough? How many of these are you going to need to build a small base? TLI puts just over 50, which is better, but not by much. Starship’s 150 tons is a colossal amount of material to place on the surface, and you put that there with really only the cost of fuel and maintenance. It is a gigantic advantage which more than offsets the extra delta V because….. Elon has now made delta V cheap. 3. Pressurised space: how much pressurised space is Zubrin’s ‘mini-starship’ have? Just using the dry mass as a guide, we are probably talking 200m3 or less. The thing has to be small enough to fit inside a cargo starship. This simply isn’t going to be enough to support 6 people on a mars mission unless you land a hab there just like the mars direct idea. And any mission needs cargo, which takes up your pressurised space. How are you going to land the hab there? So now we need a cargo mini-starship, a hab and pressurised ‘mini starship’, which all need to be placed on the surface of mars within meters of each other, and the hab stays there. Starship has so much internal volume that you could deliver 75 tons of cargo to the surface AND provide 500m3 of pressurised space (half the size of the international space station) in a single vehicle. That can easily act as the hab, the transfer vehicle and the cargo vehicle to support a six person, yearlong mission to the Martian surface. Easy peasy. I’m a big fan of Zubrin. Mars direct was a great architecture, but we are about to enter a different era of spaceflight. Starship will mean we don’t have to do things on a shoestring any more - every meter of deltaV is just not that critical when you can just refuel your reusable vessel in orbit. He needs to get with the program.

[@KipIngram]

Great great talk!

[@michaelrausa1909]

We know life was their first

[@razor6888]

Space X please hire Dr Zubrin.

[@JFrazer4303]

It's too bad that orbital fueling of upper stages is still an unknown. It helps anything. For anything we send to LEO with an upper stage for going further, some 45% is just the oxidiser in the upper stage. It has never made sense to send your Earth-LEO upper stage with it's landing requirements to Mars or the Moon. If the dry mass of the "Starship" is 85 tons, it's as bad as sending a Space Shuttle to Mars. We need an upper stage of the BFR that's for sending the tuna can to Mars or the Moon, not the "Starship". I'm willing to bet that as NASA is looking at "Starship" for its Lunar plans, what they're looking at is the lift capacity of the launch stack, not sending an expendable "Starship" like vehicle. Not at all the aeroshroud that sent it up from the ground. Modify the BFR to throw tuna cans.

[@MULHATTON1851]

There's way better technology available than Rockets and there has been for a long time now. Let's get out of the "Dark Ages" of Air & Space Travel once and for all, the Future is Ours.

[@jimmyzhao9748]

I am sad to think that what's holding this project back is lack of *money*

[@jshepard152]

In almost every talk he gives, Zubrin says that lack of money is not what keeps NASA from going to Mars.

[@stellieford9139]

Team Bubolaq agrees!

[@MrGlenspace]

Read today’s space.com on the issue of getting funding for Artemis from Congress.

[@marktuyet]

The guy using the slide projector is engineering a craft to Mars ? Really ?

[@michaelrausa1909]

2.2

[@murrayflewelling1258]

NASA MARS PLAN - Never Actually Sending Anyone !

[@CapinCooke]

@ Murray Flewelling ... Now damn, that right there is funny 😁

[@murrayflewelling1258]

@@CapinCooke Thank You :)

[@3gunslingers]

Dr. Zubrin why would SpaceX ever want to invest any money to develop anything other than the Starship? With the TLI and LEO mission modes SpaceX would need to develop and build an entirely different spaceship AND lander! This would be insane, financially! The tanker version of Starship is just an empty ship with stretched tanks for the extra fuel, no huge development investment here. You want to deliver satellites to LEO? Just cut a Space Shuttle like door into a Starship frame. You want to go to Mars? Just throw what ever you need into the payload bay and refill in LEO. Off you go. Dr. Zubrin, you are an earospace engineer. You should understand what it means in therms of manpower and money to develop TWO (or even more) entirely different spaceships, compared to build many spaceships of ONE kind in series. With the new stainless steel architecture the cost of an individual Starship will be minuscule compared to the development cost of itself and especially compared to the development cost of additional space ships and lander.

[@prof.m.ottozeeejcdecs9998]

Stuck in the past...

[@donaldmccann2049]

Between Dr. Zubrin & Elon, civilians will be inhabiting Mars and the Moon before NASA gets back to the Moon!! That is a sad commentary on what politics has turned NASA into!!!

[@jimmyzhao9748]

He tells a good 'Story', but that is all he is,... a storyteller.

[@albertgerard4639]

funny he thinks starship is too big

[@gkossatzgmxde]

Zubrin the Mamoth of Mars, makes a big thing small. Thats why he has achieved nothing in 40 years and Elon much in 4 years.

[@AlexSmith2]

May I humbly suggest videoing the talks in at least 720p (ideally 1080p) as some of the slides aren't legible :(

[@Illisil]

They aren't legible because he's been using the same images since the 80's

[@dohpam1ne]

I love the Mars Society's content, but for the love of god, why are you uploading videos in 480p? Probably 75% of the audience members have phones with higher quality video recording. We can't even read the slides because the resolution is so bad.

[@Wonderlikechild]

at least we can hear it without turning our speakers all the way up this time... :/

[@JamesBurkTMS]

This is what we got from NSS, I am cringing more than you about it.

[@DanielOutdoors]

I mention this last year... I cannot be a mamber all the way from Norway and follow anything with a quality like this...

[@pulesjet]

What about people living in the boonies ?

[@qstunrr]

Hahaha

[@strategicthinker8899]

I hope dr. Zubrin sees humans on Mars before his death. It would make his lifelong dream come true. A life well lived.

[@leecaste]

Dr. Zubrin should talk to Elon in person.

[@GlanderBrondurg]

Robert Zubrin and Elon Musk are pretty good friends. Zubrin was one of the early consultants Elon Musk contacted when SpaceX was first incorporated, and for many years Elon Musk was a trustee board member of the Mars Society. I would say that a phone call from Zubrin to Elon Musk would get through almost immediately.

[@leecaste]

GlanderBrondurg didn't know that, thanks 🙂

[@ErkiEntveg]

@@leecaste Go watch first 5 minutes, Zubrin talks about getting to know Elon for the first time and aftermath: kzbin.info/www/bejne/qIeliJJmod2kb7M

[@mjv1121]

Zubrin is stuck in a historical mindset. Starship CANNOT stage because it is a single vehicle. To develop his "mini starship" adds $5-10+ billion to the project. He is fixated with delta-v and cost as only a function of specific purpose, but Super-Heavy/Starship is all about reusability. SHS can be used for ALL launch requirements (to VLEO and beyond) because its reusability makes it cheaper than all "traditional" vehicles. Also, the change to stainless steel greatly reduces the cost of each vehicle, so the time between going to Mars and being used again becomes all but irrelevant. Starship is not a Mars only vehicle it is a jack-of-all-trades at a lower cost, BECAUSE of REUSABILITY. Stop thinking about delta-v and start thinking about manufacturability and reusability.

[@TraditionalAnglican]

Because of the huge amount of fuel carried on Starship & that fuel’s high specific impulse & thrust, Starship can provide enough Delta-V to enable a 3 month transit to Mars. &, because 2 passenger Starships would be sent at one time, they could be tethered to provide spin gravity for the trips to & from Mars.

[@mjv1121]

@@TraditionalAnglican I don't see it being at all plausible that two starships could be tethered. 3-6 months transit is probably good enough without AG anyway.

[@AlexM-wq7in]

@@mjv1121 Isnt there a great deal of logic to having a stage that can return to Earth in a week and be refueled again to be used for dozens (or hundreds) of missions in the same time it takes Starship to make a single round trip? Turnaround time is important for fully reusable vehicles. Dividing the fixed cost of the stage by flying more reduces the cost per flight.

[@mjv1121]

@@AlexM-wq7in Perhaps there is, but who is going to build it?. Starship is Starship, it is designed to accommodate as many mission profiles as possible to LEO, GEO, Moon, Mars, with only three variants: passenger, tanker, and "chomper", and possibly point-to-point. It can achieve this at the lowest possible development cost by being designed to maximise manufacturability and reusability. Zubrin's pretend "mini-starship" would mean developing an entire extra vehicle and redesigning Starship itself to be stageable but also still be able to re-enter. His idea is to reduce the burden of fuel production on Mars at the cost of risking the economic feasability of development in the first place. By first making Starship a manufacturable, reusable, and economic success, the first few (half dozen or so, or more) Starships to Mars can be treated as expendable.

[@jeffvader811]

@@mjv1121 I would agree with that. SpaceX is a commercial entity with not a lot of funding, which is why they have gone for this 'swiss army knife' minimal development architecture. I imagine that if Starlink starts making them the $30-$50 billion a year that's been predicted, or if NASA expresses an interest in utilising Starship, then they might change this layout for something more specialised. I do wonder how Astronaut selection and surface operations will work in a completely commercial Mars mission. I have a feeling that SpaceX may lease out their Starship to get NASA's astronauts on Mars instead. At least in the short term.

[@LuciFeric137]

Dr Zubrin you're an inspiration. Thank you. I've been studying your concepts for years. I'd love to hear more about your Uranium salt water rocket..

[@ShaunRF]

I'm not sure I agree with the mini-Starship idea. His logic is that allows you to reuse the main Starship more often. However, I have to wonder if it would cost less to just build a second full size Starship to use in the meantime than it would to fully develop a dedicated mini version. Especially with the move to stainless steel construction.

[@strategicthinker8899]

I think that's Musk's rationale and I think it's correct.

[@737smartin]

I would like to hear more about the energy requirement for making the return fuel. He said 4 football fields of solar cells would be required to produce fuel for one Starship. Is that true over a nearly 2 year generation period?

[@3gunslingers]

@@737smartin _"He said 4 football fields of solar cells would be required to produce fuel for one Starship. Is that true over a nearly 2 year generation period?"_ That's about correct. Thing is that SpaceX doesn't plan to bring the fest few Starships back at all. They want to build a base over the course of a few years with a couple of transfer windows and THEN plan to have enough energy production on mars to refill starships.

[@737smartin]

@@3gunslingers I have not seen that anywhere. Source?

[@3gunslingers]

@@737smartin can't pinpoint any definitive source for this right now. But Musk gives a clue in this animation: kzbin.info/www/bejne/qpW4iWavpamJras And he has talked multible times about this in the last two years on a few occasions. Also it would be really dumb to even attempt it. Like Zubrin said it costs a fortune in cargo to refuel a starship on mars in under 2 years. Also if SpaceX get their first few starships back from mars it will be about 3 years after their launch. Which means they are already at least on their second generation of starships by then. So they wouldn't reuse any of those anyway. Now tell me why SpaceX would spend so much money and cargo to get their first few starships back?

[@anastasiaprosina2689]

For those, who wanted the presentation: www.nasa.gov/pdf/376589main_04%20-%20Mars%20Direct%20Power%20Point-7-30-09.pdf

[@pulesjet]

Use retired BFR's to build the Braun.

[@JGZimmerle]

If it should prove difficult for a private company from Earth to launch a nuclear reactor to Mars, maybe they could launch an unfuelled nuclear reactor, and use ISRU to fuel it at the destination. To avoid the difficulties of isotopic enrichment, it should be a fast reactor, probably best to use a molten salt reactor like the one from Moltex Energy or the one from Elysium Industries.

[@BeKindToBirds]

are you suggesting enrichment on Mars? It is already hard enough here!

[@enjuaihara2576]

we need to get off this planet already go Starship

[@cardcounter21]

Zubrin recently said that we will be on Mars by 2030. Why do I get the feeling in 2030 he will be saying we'll be on Mars by 2040!

[@ChrisMarshallUS]

How long would it take to produce the fuel on Mars needed for option 1?

[@bzqp2]

Probably he's talking about the whole Mars-stay from landing to return. With the conjunction transit sped up to 6 months it would be around 18 (up to 24) months. But I guess if you want to know the direct details you need to buy a book. :P

[@theOrionsarms]

Nobody thinks to pile 500 tons payload onto one of the starship after putting it on LEO, pushing in a elongated orbit refueling again with a tanker that put in the LEO too and refueled onto orbit, and send it to the Mars. Advantages in this case are obvious only one ship it's blocked in four years journey to Mars and back plus waiting window to next trip, you need to build minimum four ships :two tanker, one cargo ship to transfer payloads and the ship that make the travel, but can use again three of the ships from another purpose in the earth vicinity. And you have a method to land on the Mars, that is better than sending small payload with its own landing devices attached.

[@TraditionalAnglican]

That’s actually a good idea - Load the cargo ships with both fuel & more supplies once they get into orbit. That especially makes sense if we’re loading rocket fuel production machinery, food, emergency water, water purification equipment, an MSR, inflatable habs, collapsible greenhouses, Mars Rovers & autonomous assembly robots into one or more cargo BFR’s.

[@theOrionsarms]

@@TraditionalAnglican I don't know how would behave from aerodynamic point of view a starship with 500 tons or more payload when it lands on Mars!, but if you think of roket propulsion having a biggest payload is better, in the original plan use only a single engine for landing and throttling to 25%for a soft landing. With sixth engine limit is only how much can put in to and landing safely. I consider a hibrid ship from pasager and cargo a bad idea, for initial development would be necessary a large amount of equipment and supplies, this is method can be delivered.

[@TraditionalAnglican]

Vasile Sulica - I thought “stuffing a Cargo Starship to the rafters” with 450+ total tons while in orbit might be worth consideration. If that worked, the colonists could start out with more equipment, greenhouses & supplies, along with better habs, than would otherwise be possible. I agree - Aside from equipment & supplies needed for the trip over & immediately after landing, the room in the Passenger Starship should be reserved for the passengers.I,also believe the Passenger Starship will need to have 50t more dry mass to accommodate extra radiation shielding, water recycling, food refrigeration, storage & preparation & passenger & crew accommodations

[@theOrionsarms]

@@TraditionalAnglican for the passenger ship if you make a another refueling after pushing onto a very elliptical orbit, can reach a higher speed and make a shorter trip maybe three or four months, and reduce the amount of radiation by half, if you make the same maneuver around the Mars then can have ship back into six months or eight , and having a year and a half of reusing that ship into vicinity of earth before next window to Mars re-open.

[@pulesjet]

Your working with Space X, Right ?

[@Sonofdonald2024]

Love the book. One annoyance is the audiobook version is not available in the UK. Any reason why? I listened to a snippet on audiobooks.com but when I went to purchase it was told not available in my region

[@michaelrausa1909]

Not about what you know it’s what you can prove it’s like we need lawyers to be explore

[@RichRich1955]

All the turtles I normally see on the river for some reason are completely gone this year.

[@jasons44]

spaceX has confused me with this hopper, and its shape from s.s

[@TraditionalAnglican]

The Passenger Starship would probably be heavier than the Cargo Starship in order to provide radiation shielding for the passengers. I believe we already have a “Lunar Mini Starship” in Development - It’s called “Blue Moon”, and Starship could carry 3 cargo versions/2 manned versions (single launch, unrefueled) or 8 cargo versions/6 manned versions (single launch, refueled) to lunar orbit.

[@akaikiseki9346]

Lol nope Having humans in a ship is basically throwing a semi-empty Starship. You need air, rooms, and your shield can be the water needed for your humans. Hydrogen bodies absorb radiations very nicely !

[@TraditionalAnglican]

Akai Kiseki - I’m saying that, because of the need for radiation shielding & on ship water reprocessing, the Passenger Starship would be heavier than the Cargo Starship before Passenger/Cargo loading. This would be true even if you used the water for radiation shielding. A Passenger Starship would hardly be empty, as it would have Passenger Accommodations, food, water, air (& air purification), EVA suits & whatever supplies the Passengers would need to use on the trip over & during their first weeks on Mars...

[@markcaseon7136]

What about Propane and Acetylene for rocket fuel?

[@3gunslingers]

The specific Impuls of those is too low and they are pretty difficult to make on Mars.

[@InquisitorMatthewAshcraft]

@@3gunslingers Not to mention, those would fry engine components rapidly, even more quickly than hypergolic fuels.

[@stevemickler452]

Power constraints could be eased by beaming the power down from orbit via microwaves. If solar electric cargo vehicles are used they can deliver cargo and remain in orbit to act as solar power sats. Dust storms are not then a problem and you get much more power per IMLEO than surface solar since this has to be landed and you have to store power for night. Power can be constantly supplied once several SPS units are in place. In addition, these sats could provide power to any location while providing GPS and communication. It would make sense even if chemical propulsion is used to transport the power sats.

[@3gunslingers]

And who's going to pay for the development of solar electric cargo vehicles, solar power sats and SPS units? SpaceX certainly not.

[@MrMonkeybat]

The way Musk is churning out prototype Starships shows the benefits of economies of scale and the cost-effectiveness of stainless steel. So I doubt having lots of specialised craft and smaller launch vehicles will be much cheaper than mass-producing stainless steel starships, which gives you a big cargo too.

[@sudheeraggarwal570]

One thing... Elon has already scaled down from 500 tons capacity to 150 ton.... Now zubrin wants it to scale down more.... Strange.... After few days he will come with a theory to scale up.... I will not be surprised.

[@Bitchslapper316]

I think he is oversimplifying the process of making fuel on mars. He is explaining like a ship lands there and something magically digs up and and runs reactions on the chemicals and turns them into rocket fuel. With our current technology we have issues scooping up a bucket of Martian soil and running it through a filter to try to see what's in it. It would be a huge leap for an automated system to open a mining operation on mars along with a chemical propellant factory.

[@3gunslingers]

@okgo 123 Only when we bring the hydrogen from earth. If we want to use martian Water, we have to send astronauts first, before we can refill ships.

[@MULHATTON1851]

DR. ZUBRIN WE'RE PROMOTING YOU TO THE RANK OF ADMIRAL IN STARFLEET COMMAND. CONGRATUALTIONS. WELCOME ABOARD.

[@Deovera94]

We can only go back to steam power. Mars is the steampunk planet.