Why SpaceX is Using a New Fuel

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Credits:
Producer/Co-Writer/Narrator: Brian McManus
Writer: Barnaby Martin
Editor: Dylan Hennessy
Animator: Mike Ridolfi
Animator: Eli Prenten
Sound: Graham Haerther
Thumbnail: Simon Buckmaster
References
[1] Rocket Propulsion Elements, 8th edition [Sutton, 2010]: archive.org/download/Rocket_P...
[2] global.jaxa.jp/projects/engin...
[2a] space-scitechjournal.org.ua/en...
[3] www.lpi.usra.edu/meetings/lea...
[3a] link.springer.com/chapter/10....
[3b] arc.aiaa.org/doi/10.2514/1.2672
[4] www.researchgate.net/publicat...
[5] www.journal.csj.jp/doi/10.124...
[6] www.nature.com/articles/natur...
[7] www.nature.com/articles/s4146...
[8] www.mdpi.com/2073-4344/8/12/578
Select imagery/video supplied by Getty Images
Thank you to AP Archive for access to their archival footage.
Music by Epidemic Sound: epidemicsound.com/creator
Thank you to my patreon supporters: Adam Flohr, Henning Basma, Hank Green, William Leu, Tristan Edwards, Ian Dundore, John & Becki Johnston. Nevin Spoljaric, Jason Clark, Thomas Barth, Johnny MacDonald, Stephen Foland, Alfred Holzheu, Abdulrahman Abdulaziz Binghaith, Brent Higgins, Dexter Appleberry, Alex Pavek, Marko Hirsch, Mikkel Johansen, Hibiyi Mori. Viktor Józsa, Ron Hochsprung

[@zenithparsec]

The reason it burned with so much soot was it was a deliberately fuel rich mixture. If they ran the engines at perfect stoichiometric ratios, they would have melted. And some of the soot is from the turbopump. And the ratio could be changed to "throttle" the engine via the engines' "Propellant Utilization" valves. (It's not actually throttling, but had a similar thrust modulating effect . )

[@mcg7996]

Came here to make this same comment. Black exhaust you see at ignition is turbopump spinning up. Then in the main exhaust plume you can see the color change between the turbopump exhaust and combustion chamber exhaust.

[@evil0sheep]

my understanding was that most of the black soot you see is actually the exhaust of the fuel-rich gas generator being used as film cooling inside the nozzle of the main engine, not the main engine running below stoichiometric balance. Like the main combustion chamber they run hot but then to stop the throat of the nozzle from melting they flow the relatively cool exhaust from the gas generator powering the propellent pumps between the walls of the nozzle and the hot gas from the main combustion chamber

[@garethbaus5471]

@@believeinjesus6972 no thanks.

[@williamchamberlain2263]

@@believeinjesus6972 Judges 21: doing mass murder and kidnapping little girls is all part of god's plan.

[@wstavis3135]

@@garethbaus5471 just report it as spam.

[@hughjass1976]

"Where I can inspire, brilliant can educate" Don't sell yourself short man, you've taught me a hell of a lot

[@hughjass1976]

@John Thomas no idea who you're talking about

[@General12th]

@@hughjass1976 You're _definitely_ a big fan of Big Clive! Don't deny it!

[@hamzamahmood9565]

Must be a loot of moneyy

[@sallyl.9606]

@@General12th who is that

[@believeinjesus6972]

Repent to Jesus Christ “Let us then approach God’s throne of grace with confidence, so that we may receive mercy and find grace to help us in our time of need.” ‭‭Hebrews‬ ‭4:16‬ ‭NIV‬‬ h

[@JaredOwen]

Love the 3d models😃

[@notinuseanymore9481]

18 likes no comments? Hellow Jared owen

[@robbertsprezzatura7220]

Great fan of you!

[@Man-of-Steel674]

'Course you do.

[@VistokDB]

Omg hello im a fan of you, nice meeting you jared!

[@daviddempster402]

Methane LOX is very clean. It also allows for the use of co-axial fuel tanks where the LOX tank is surrounded by the Methane tank. This creates a very strong and efficient structure while decreasing the weight of the LOX tank.

[@superspies32]

But I think its also very dangerous. If the tank somehow leaked just a few of those gases together, Elon Musk will have to face Colombia disaster happened somewhere between Mars and Earth

[@gePanzerTe]

Plus Methane can be obtained with... poop 🤗🚀 It is very easy (some farms and rural facilities do that) and it's named Biogaz

[@kineteks77]

A note about sooty rocket exhaust - a few times you talk about how sooty rp1 is and at the same time show a bunch of relatively dark black flecked exhaust from a Saturn five launch. Yes the combustion is relatively incomplete which is why we can see the yellow flame but it isn’t like what you show in these clips. That part of the exhaust comes from film cooling, where they purposely ran fuel rich mixture around the outside of the nozzle to keep it from overheating.

[@MihkelKukk]

Thank you, a very important detail there. Although he isn't wrong about the soot, the example (at least for someone who knows more deeply what's going on) was poorly chosen. It does also still get a point across.

[@MihkelKukk]

A video for those more interested in film cooling, and many other cooling options that have been developed for rocket engine nozzles: kzbin.info/www/bejne/npbCc39shpqoZ7s

[@pseudotasuki]

And it only appears dark because the cameras are set to film the extremely bright flames.

[@sadomor6179]

@@pseudotasuki Even though the camera setting may make it look darker, it really is a almost black smoke, you can see this nicely with the merlin enigine testfires, its a different engine, but the same cycle type

[@whitenoise509]

@@MihkelKukk Great info in this one, thanks!

[@fraserhenderson7839]

Albert Einstein said something like "if you can't explain it simply, you don't understand it yourself". I think Albert would approve of this video.

[@amosbackstrom5366]

Except the critical equation isn't balanced and the hydrogen isn't represented correctly. It makes it very difficult to even understand his point about producing enough oxygen.

[@allanbrogdon3078]

My teacher in airframe electrical, Jerry Adams said "I will teach at the level of the best student in the class.It wasn't my best subject but I wonder if he was mostly assigning things and not knowing.I was curious about his use of "device when describing anything electrical.I looked the definition up and told him his usage was incorrect.He acted insulted but I passed.

[@furriesinouterspaceUnited]

​@@amosbackstrom5366or maybe your just not fast enough to understand it

[@treborobotacon]

I would like to hear Albert Einstein's simple explanation of gravity.

[@furriesinouterspaceUnited]

@@treborobotacon space blanket with bowling ball rolling around on top

[@blackmesaresearchcorporati6764]

3:25 THAT SHOT That just has to be the most breathtaking shot of the Saturn V ever

[@williamkennison8920]

This is the 1st I've heard of this technology. It is KISS simple and one of those things that was right in front of us all this time. Brilliant!

[@Michaelonyoutub]

Another benefit of methane is that since it has a similar boiling temperature as oxygen, not only can they use similar infrastructure, they can also be stored right next to each other in the rocket with minimal insulation which is not possible with hydrogen and oxygen or kerosene and oxygen, since the differences in the boiling point for those liquids is too much. This save space, simplifies components, and saves on the mass of systems within the ship to cool the propellants since you can use one system instead of two separate ones. All of that really helps when you want to mass produce those systems and tanks for as cheaply as possible.

[@breadstealer93]

very cool

[@mcrvids6860]

Isn't one of the advantages of an LH2/LOX with a common bulkhead that the temperature difference creates a vacuum within the bulkhead and thus insulates even further?

[@edbunkers4516]

Methane is highly damaging to ozone, though

[@Michaelonyoutub]

@@edbunkers4516 it is not damaging to the ozone, it is just a potent greenhouse gas

[@imconsequetau5275]

@@mcrvids6860 No.

[@davidlloyd3116]

I can thoroughly recommend reading “ignition!”, it is absolutely packed with information and they should make a film of his career as a rocket propellant expert. They even used liquid mercury once as a propellant. He also talks about using chlorine triflouride (which actually burns concrete on contact!) as a propellant too, among myriads of other types.

[@kayakMike1000]

Chlorine Trifluoride? Bafwa! That is the most potent oxidizer ever. I hear a Chlorine Trifluoride tank ruptured and caused a meter of cement pavement and dirt to burn for six hours.... It's remarkably hard to contain it, I think it requires stainless steel tank... But one minor defect in the tank and it burns right through!!!

[@davidlloyd3116]

@@kayakMike1000 As a virologist we'd need to store our cell lines in liquid nitrogen, so as you decant LN2 from one flask to another, liquid oxygen drips off the metal transfer tube. One of the engineer's tricks was to collect the LO2, take a mouthful and blow it through a lit cigarette. Instant flamethrower! We're a bit more safety conscious nowadays!

[@extrastuff9463]

The FOOF and ozone chapters were interesting too, actually the whole book was very enjoyable. I should really take the time to read through it again sometime soon. Many substances that were tried seem a bit insane to even want to work with. Dimethyl mercury also vaguely stands out as one of the mad things they experimented with at one point. The mystery of disappearing ethanol fuel and happy researchers + sailors was funny too. Even after adding things to make it not fit for consumption, I was kinda curious how often that went wrong and if saving it from combustion ever went beyond just distilling it again.

[@satyris410]

@@davidlloyd3116 Totally off-topic but we're here now - I used to have fun working in the lab as well, also a virologist. LN2 was fun as was dry ice. We'd get reagents shipped on dry ice, I used to put it into one of the big sinks and blast the high pressure hot tap on it and fill the room with billowing clouds of water vapour and co2. probably quite dangerous but it's denser than air and sinks. Also using LN2 to clean the lab floor. when you pour it out of a dewar onto the floor it scoots along and picks up any dust as it bobbles about in the Leidenfrost effect. One weekend I was working and took a bottle of fresh lemonade with me, I put it in a bowl with some dry ice to make a sorbet, but it ended up fizzy, I should really have used liquid nitrogen. One of my biggest regrets is when I got my mate a job there and was showing him the prep room. there was a bottle of concentrated HCl 37% I told him it smelt vinegary expecting him to do the proper scientist sniff and waft some towards your nose with your hand, but he just put his nose over the bottle and huffed. It stung his nose and he coughed out a cloud of hydrogen chloride gas. not particularly pleasant, but he was not permanently harmed.

[@StrangeTerror]

@@satyris410 lmao like a true chemist: "not permanently harmed"

[@peter_david_7733]

"We have been given the scientific knowledge, the technical ability and the materials to pursue the exploration of the universe. To ignore these great resources, will be a corruption of a God-given ability" I just love this opening address ❤️

[@PracticaProphetica]

It's not true. Not everything that man has the ability to do, should be done. Jesus had the ability to make stones into loaves of bread, in the wilderness of temptation. He wouldn't do it, because that is not what God put Him on earth for. As a race, we face destruction from many sources: war, environment, economic. Every time a new invention comes out, we manage to turn it into something that hurtles our race towards extinction. We are not fit to colonize other worlds until we solve our own problems at home.

[@kevinmaher7687]

Same isn't this the German American in the opening Wernher Vonn Baun one of the most important rocket developers and champions of space exploration

[@PDVism]

@@kevinmaher7687 And yes, that's Wernher Von Braun, one of the Nazis that the USA just happen to forgive and forget that he was a war criminal and instrumental in the V1 and V2 bombing of the UK. But hey... so what eh, as long as he mentions god and lays the foundation of the USA's rocket program.

[@gePanzerTe]

​​@@kevinmaher7687 Von Braun, disciple of Oberth (Germany). Count also Tsiolkovsky and Korolev in the east, Esnault-Pelterie in France and Goddard in the west. 💫🚀 Ad Astra !!

[@louisb229]

I remember watching it on our black and white TV. People went running out of their homes and businesses yelling "we've landed on the moon...we've landed on the moon". In 1973 we got the World Book Encyclopedia and I loved looking at all the colored images under the space section.

[@msebastien24]

Soviets had already developed mathalox rocket engines : RD-0162, RD-0141 & RD-0143, RD-183 & RD-185. Unfortunately, they never flew on a real rocket, only static fires had been conducted.

[@benjaminreinersman9753]

Don't compare r tech to Russia there stuff works unrest like there tanks

[@Project_1143M]

@@benjaminreinersman9753 thier tank is quite good on its own imo Just that it poorly maintain and the crew lacking

[@rakaydosdraj8405]

@@animeee82 the SOVIETS had good (VERY good) rockets. The russians are still using rockets developed 60 years ago, and their native russian designs (Angara) are plagued with problems. And Russian R7 variants are having more and more problems as the ex-soviets retire from the program.

[@fransschepens3]

Fake moonlandings

[@rakaydosdraj8405]

@@fransschepens3 Oddly suspicius radio returns where Apollo 12 claims to have set up a radio retroreflector... Looks like a retroreflector.

[@JainZar1]

Another reason they went with Methane is that is allows the full flow staged combustion cycle of the Raptor to work. The Merlin uses uses Kerosene and has minimal to no refurbishment required.

[@pseudotasuki]

Indeed. It would be extremely difficult to implement in an engine that burns hydrogen, due to the enormous difference in density (and therefore frow rate) of hydrogen and oxygen.

[@pseudotasuki]

The only other full-flow engine to reach a late stage of development was the USSR's RD-270, which burned the similarly dense (but extremely toxic) hypergolics UDMH and N2O4.

[@spacelapsus8835]

It's the other way around actually. Since they're going with methane they chose to develop a full-flow stage combustion engine. The choice of the propellants is a level above the choice of the thermal cycle because it influences your architecture a lot more.

[@pseudotasuki]

@@spacelapsus8835 I see it as sort of a package deal. Along with the other reusability benefits of methane, you also get the relatively benign turbopump environments.

[@spacelapsus8835]

@@pseudotasuki yeah that is for sure true. However, what I meant was that you first have to settle on a propellant to then start considering the architecture of the propulsion subsystem. The choice of the propellant is governed by the type of mission you're dealing with. For example, long term missions generally (it's not always the case but it is often true) won't opt for cryogenic propellants for the final stages because of the complexity of storing at such low temperatures for extended periods of time. In this case, the choice of methane came from the possibility of in-situ extraction and the better performaces compared to RP1.

[@uncommonlogic1698]

Great video. Thank you for the explanation of the importance of Discovery and Space. People don't know the massive impact of innovation driven by discovery and just trying to understand our universe.

[@osamahebala6923]

This is a great video, nicely summarizing so many topics & ideas.

[@Knirin]

By the way that 400C reaction temperature for the Sabatier process is about 200C below the operating temperature of the MSR built at Oak Ridge National Laboratory. Most Solar Thermal systems using molten salts operate around 600C as well, so there are several options for cheap thermal energy to run the reaction.

[@xermasboo5401]

But it is Nuclear, and people don't want to acknowledge there are distinctions and places it can work meaning Politicians will fan the flames on why we should not bother.

[@TheSpacecraftX]

The darker exhaust on the Saturn launch is because there is fuel sprayed down the sided of the nozzle to provide cooling. Not all kerosene rocket exhausts look as dark as that.

[@maxvanvijfeijken2699]

I'm pretty sure it's actually fuel-rich exhaust from the preburner that is funneled there to cool it

[@PBMS123]

It was sprayed on the side of the Motor Nozzle. It was pumped through pipes around the nozzle.

[@IntelTV]

@@PBMS123 This is correct

[@blackhatfreak]

He's a muskrat and they're not known for their intelligence

[@jessepollard7132]

NOPE. fuel is used to cool the engine - but it is then cycled back into the combustion chamber.

[@brentboswell1294]

The world's first rocket engine designed to be reusable- the Rocketdyne RS-25, is a liquid hydrogen/ liquid oxygen engine. I'd love to know how hydrogenization affected the engine. As I recall, the engine was designed for 25 launches. As I understand it, three of the four RS-25's being used for Artemis 1 are leftover, flight used shuttle engines

[@nickmcdonald3083]

Hydrogen embrittlement is likely what puts the 25 launch limit on the engine. Spacex is trying to design their rockets to be indefinitely reusable.

[@rdragonsheridan]

That is an incredible accent!!! It really adds to the quality of your content. Great job!

[@BezBog]

These slow motion shots of the Saturn V never get old. This was truly an awe inspiring moment in human history

[@jimsvideos7201]

That was the Saturn V though.

[@oscarpeters5309]

do you mean saturn v, i mean the atlas v looks great as well

[@dannypipewrench533]

That is the Saturn V, but the Atlas V is really good too. Ares V was going to be great, like SON OF SATURN V great. Titan V would have been great, but Delta and Atlas were favored over Titan. Titan V would have been a hydrolox system instead of aerozene-50/N2O4, and would have had first and second stage extensions, by ten feet each. Possibly even diameter increases, perhaps to 15 feet on the first stage, much like the Titan-based Barbarian proposals. Delta V (Not delta-v) is more or less what Vulcan will be. Vulcan could perhaps be Atlas VI.

[@Michaelonyoutub]

my favourite shot of an engine firing was a slowmo shot of space shuttle engine test where the outer rim of the rocket bell had icicles on it from the super cold fuel flowing through it to cool it down, and right next to those icicles was the engine firing full throttle with a bunch of clear blue exhaust. The duality of super cold right next to almost surface of the sun hot, was super cool, and really shows just how much insane engineering goes into making these things that allows them to achieve that.

[@imconsequetau5275]

@@Michaelonyoutub That was a throttle-down test to a minimal thrust setting. At full thrust, no icicles.

[@francescogiuseppearagona1109]

I see a couple of errors here: -1 sometimes hydrigen is referred to as H, while it is H2, as correctly reported sometimes. Some equations are also wrong, such as the one at 9:11 4H2O → 4H2 + 2O2, then 4H2 + CO2 → 2H2O + CH4, but these are kinda minor imprecision. -2 coking in the engines is not much caused by long chain hydrocarbons, rather by alkenes and aromatic hydrocarbons, which are naturally present in kerosene. RP-1 is a highly refined kerosene that eliminates much of the olefins and aromatics, but as of my understanding it's impossible to get rid of 100% of them. -3 The black soot you see at the exhaust of Saturn 5's F-1 engine is not caused by poorly burned fuel, but from fully unburned fuel that was used as nozzle coolant. This fuel was unburned, because it was just for cooling, so a large formation of soot is expected. -4 You wouldn't want to convert captured CO2 back into methane because in order to do this you would need at least the same amount of energy that was obtained by burning the hydrocarbon that generated it, rendering the whole process useless. Of course, you can store it and revert it back to hydrocarbon when you have overproduction of renewables, but this is still not really recommended. The best we can do with captured CO2, as for now, is just to bury it underground and leave it there forever, using something like zeolytes or MOFs to stabilize it. Think of these as sort of a CO2 sponges. Anyways, very interesting video.

[@2hedz77]

Yeah I am surprised more people didn't catch this...I was counting my moles and they didn’t add up! Thanks for also the very detailed add'l info 👌Of course making CO2 into fuel is not a great idea in and of itself, but unfortunately there's not market for CCS currently. No one will pay for something you can't use...even if it will save civilization 🙄. So to create (kickstart) the market, rocket use is a much better idea than allowing oil companies to use it as a crutch.

[@2hedz77]

@12:17 did you find an error in the final eqn for the 'Hydrogen Transport' final eqn too? Requiring 2 moles O2 for every 1 of CH4), I get: 5CO2 + 4H2 -> 4CO + 2H2O +CH4 + 2O2 compared to video: 3CO2 + 6H2 -> CH4 + 2CO + 4H2O . Both eqns are balanced...but since the product oxygen (needed for subsequent combustion) is omitted in the products I think the molar coefficients in the video are in error. Is this correct?

[@mariusjansen5345]

well than someone have to tell Elon that. ... lol. so u just use solar to convert. The whole point of "reusable" is to "generate" fuel on mars and fly back. In other words u have to find something that u can burn in a rocket motor, its no matter what u have to do for that. As long as it works.

[@stevennicholas5472]

@@mariusjansen5345 This first Mars mission is a one-way trip; they aren't coming back. What would be the point of bringing them back? They are going there to establish a beach-head and to survive for as long as they can, ensuring the next wave has a head-start. I'd love to see the psychological tests that were done on the people that were selected.

[@stevennicholas5472]

H2 as in H2O is actually two hydrogen atoms linked with 1 oxygen atom, so hydrogen is H.

[@InservioLetum]

Humble as always, informative as ever, and honestly fantastically structured, paced, and cut. Brilliant's got nothing on you my friend. Don't sell yourself short.

[@ronjon7942]

I’ve a better feel for specific impulse after watching this. Viewing total impulse as the area under the total thrust curve really helped. Maybe after watching this a few times will help solidify specific impulse for me. At any rate, I found this video to be the best description of the metric to date. If anyone has links to links that you found helpful, I’d appreciate it. Suppose I could (gasp) search KZbin or DDG….

[@mauzen_]

These videos are always so well done. The quote at the beginning really draws your attention and sets the stage. Really just marvelous work.

[@donaldduck830]

I just love von Braun. Greatest man (together with Korolyov) of the 20th century. I would rather lose Gandhi than them.

[@saumyacow4435]

ISRU oxygen on Mars is relatively easy because we can extract it chemically from CO2. ISRU methane is a lot, lot harder. Its not the chemical engineering, but rather its the industrial scale mining. And with ecosystem of assembly, refuelling, maintenance and repair robots that would be needed to mine the dirt, from which to extract the water. And the MW class power supply and distribution system. Fortunately, in a realistic Mars exploration mission, the quantity of methane needed is small - single digit tonnes of methane per ascent. So it makes more sense to import methane to Mars and only produce the oxygen locally. After all, the oxygen component is 78 percent of the propellant.

[@lubricustheslippery5028]

The whole Mars thing is just to create hype is not meant to be realistic or fool anyone but to rich investors that can't come up with something else to through the money at.

[@saumyacow4435]

@@lubricustheslippery5028 I'm more inclined to believe that Elon is genuinely delusional, regarding Mars at least. Btw, I love that handle :)

[@bigcauc7530]

@@saumyacow4435 why would you consider him delusional about Mars? Just curious

[@avroarchitect1793]

@@bigcauc7530 don't bother asking them. You are looking at the modern equivalent to the news paper that published a story about how man would not fly in 1000 years. Only to have the Wright bros do it within the next month.

[@avroarchitect1793]

Sounds like they are gonna need an SMR to power this. Good thing that is on the horizon too. The engineering challenges are there but with enough effort its possible.

[@cjschoenmann2258]

This is one of my favorite videos. I just did a science fair on this concept. Thank you for the video

[@kitkerames9446]

Great video! I like everything your channel puts out. But as an engineer myself, I just want to make a correction about impulse. It doesn’t represent total energy released. In this case it represents total momentum gained by the rocket due to the fuel.

[@ronjon7942]

Can you explain that further, please?

[@kitkerames9446]

Sure @@ronjon7942 . Impulse is indeed the area under a force vs time curve like the one in the video. This is also equal to change in momentum over the time the force is being applied. To see why, you'd need to integrate force and the answer would be equal to the final momentum minus the initial momentum (I'll put the math at the end of my post). So fundamentally, the impulse represents the total increase in momentum due to an applied force. That increase in momentum is related to the energy gained, but it's not a direct relationship so we can't say the area under the curve represents the energy gained. You can calculate the area under the curve by taking the integral of the force function f(t) with respect to t over some initial time to a final time: ∫f(t)dt. Newton’s second law defines force as, f(t)=ma=m(dv/dt) where m, a, and v are mass, acceleration, and velocity respectively (dv/dt is the derivative of velocity which is equal to acceleration). So the integral becomes, ∫(dmv/dt)dt=∆(mv). This result is equal to change in momentum since momentum is defined as P=mv. On the other hand, energy gained by the rocket, due to the fuel alone, is equal to the rocket's change in kinetic energy (a measure of energy associated with an object’s speed). Change in kinetic energy is ∆(0.5mv^2) which you can see is similar to momentum, but the relationship is quadratic so it will not be directly related to impulse. Instead, increasing the area under the curve will quadratically increase the amount of energy the fuel provides to the rocket. I know that’s a lot so feel free to ask any follow-ups.

[@C-M-E]

Something to digest for those that doubt the practical merit of investing time and resources into this strategy may find of benefit: dozens and more new technologies are stumbled upon through projects like this, where new methods have to be developed to tackle problems that can have additional and more widespread benefit than the primary topic of study ever envisioned. I myself often run into this, where I started on one specific target, and through the development to get the primary idea off the ground, end up developing 5 or 6 new application ideas along the way which likely have more practical and widespread use then that initial project ever could encompass by itself; occasionally you stumble onto something so magnificent that switching to one of those accidental discoveries is worth abandoning or postponing the first project because of said possibilities!

[@Iron-Bridge]

Yes. Pretty similar to the ancient alchemists and transmutation chemists of the past. Wouldn't have a periodic table and other development otherwise.

[@TariroNgorosha]

00:19 that ignition onrush of gasses that get sucked back in by the negative pressure zone/vacuum created by the rapid exhaust leaving the chamber always tickles me. Gas goes up and reverses, so simple yet wonderful.

[@frayedsanity]

Very cool stuff. Nice to know how they're trying to work towards improving the atmosphere.

[@jaybanchero]

I encourage everyone to think through the "climate change consensus" that has attributed the "problem" to CO2. Several counterpoints to consider: 1. Vostock ice cores show unquestionably that past atmospheric CO2 concentrations were more than an order of magnitude greater than today (long before SUVs). 2. The atomic weight of CO2 is 44 yet the average atomic weight of the atmosphere is a smidge below 29, therefore, CO2 only exists in trace amounts in the upper atmosphere (put there primarily by volcanism). CO2 is mainly confined to the lowermost strata of the atmosphere which doesn't create any kind of "feedback loop" or what could in any way be characterized as a "greenhouse effect" (admittedly, CO2 does indeed absorb infra-red radiation which is a good thing... We'd likely freeze, otherwise). 3. The optimum atmospheric CO2 concentration to support photosynthesis is more than 4x what it is currently - if anything we should be ADDING MORE CO2 to the atmosphere instead of stupidly doing everything possible to remove it. Current atmospheric CO2 concentration is much closer to the starvation level for plants than it is to the past maximum (not even close). 4. Professor Ian Clark, et. al., have conclusively proven that atmospheric CO2 levels actually follow Earth temperature instead of the other way around - as suggested by the "consensus". In other words, that big glowy thing in the sky is primarily what determines the temperature on Earth just like it always has. The fact is that atmospheric CO2 levels adapt to temperature (with an approximate 800 year delay). It can be argued that the only things "driven" by CO2 are bubbly beverages and plant growth. It can also be argued that the "demonization" of CO2 is more about power and control than it is about solving any kind of real problem. We desperately need to re-open the debate across all venues - only this time with all points of view given a seat at the table instead of the agenda driven echo- chamber we've had since the beginning of this so-called debate (from all sides).

[@lukestewart6155]

Thank you so much for actually admitting that carbon is not a waste product but another resource we haven’t used yet

[@Khether0001]

The amount of research to create this video is amazing! Reminding that it is not only googling the subject, he (and his team?) had thousands of hours studying a lot to even understand and relay the subject properly. Excellent video. Congratulations!

[@MonkeyJedi99]

Ignition! is a good read on the topic of rocket fuels.

[@lii1Il]

Love your explaination of the chemistry in the process!!! Thank you!

[@RealEngineering]

Credit goes to Barney there. New team member that we are hoping can launch a third channel

[@lii1Il]

@@RealEngineering Excellent job! Thanks again and koodos to Barney!

[@stebwald7971]

@@RealEngineering Shout out to Barney! Sounds like you are a Champion among Champions! Keep showing the light!!!

[@amosbackstrom5366]

Barney didn't balance the most important equation

[@lii1Il]

@@amosbackstrom5366 and what was that?

[@cjmatulka8321]

My favorite interest in the space industry is in the launching and recovery process. Things are still primitive and the years of practical experience is beginning to pay off, still have a lot of room for evolution in both realms. Carry on.

[@bobgreene2892]

As usual, graphics are excellent, and keep pace with the narrative.

[@Maplish298]

@RealEngineering I'm starting my mechanical engineering program in fall and I must say, you've truly been my biggest inspiration, thank you

[@huwzebediahthomas9193]

Start doing your math now, ready. Get down the library! Pure and Applied. But forget Statistics, that is easy, can do that the night before. 👍😎

[@jaykparikh37]

This is the first video that’s ever explained specific impulse in a way I understand, thanks 🙏

[@johntheux9238]

Wait until you hear about the Oberth effect...

[@FastSloth87]

I guess you don't follow Scott Manley or Everyday Astronaut then.

[@VecheslavNovikov]

It's exhaust velocity multiplied by a constant. The faster you throw propellant out the back, the faster you can go on the same amount of propellant.

[@johntheux9238]

@@VecheslavNovikov That's only true for a rocket engine thought, for a jet engine the slower you throw the air the more efficient you are because you are pushing an external mass and the slower you throw it the more mass you are pushing against.

[@johntheux9238]

@@VecheslavNovikov Specific impulse is a unit of momentum per kg of fuel so if the exhaust mass and the fuel mass are the same like in a rocket engine it's just an unit of speed. But instead of using newtons they used kilogram force. So you have to multiply it by 9.81 to convert kgF to N and get a speed in m/s

[@AmateurArson]

I checked out a book at my university’s library which discusses different rocket fuels. Love this kind of stuff!

[@FrenziedMew]

Man i love your voice and everything in your vids!! super interesting, even though I know practically nothing about engineering or chemistry :D

[@joemcgonagle370]

Amazing work! I always throughly enjoy watching these videos. You do an excellent job discussing technical information in a manner that keeps engineers like us entertained while also explaining what it means to people who are less familiar with the subject matter. Keep it up!

[@infinitumneo840]

Mars would make a great base for mining asteroids in the asteroid belt and in Jupiter's L-3 and L-4 positions. There's possibly more hydrocarbons and water on these astroids as well.

[@maheshrathod5593]

@ARC Commander CT-420 how special would those metals or alloys be?.Could u give an e.g?

[@russhamilton3800]

Right...mine for what? Smdh

[@angrymokyuu9475]

Why, though? The extra complexity of lining up orbits for a "gas station", so to speak, could delay a mission for years and would add significantly to delta-V requirements as you suddenly have to stop around a third body and work its launch windows into the equations. Plus, we're likely a century or more before such things become economically viable as the moon and other near-earth objects will be able to provide resources to sate growing terran demand much quicker and at a much lower cost.

[@mikehankins4513]

Did yall not see the movie evolution? Leave them meteors where they are.

[@cerdajorge1991]

i've learned so much from your videos, like it's awesome. thank you!

[@AvrilFlower-Fortune]

"Thermodynamic equilibrium is a war of attrition that the universe will always win." - @5:49 Not just an engineering mind, Brian - quite a poet, too! Love it.

[@witchdoctor6502]

This was a great video, nicely summarizing the general idea. Also I highly recommened the book Ignition! even if you don't understand chemistry it is still a fun read that explains a lot about propellants and how we settled on fuels that are used most.

[@JESUSCHRIST-ONLYWAYTOHEAVEN]

GOD'S STANDARD FOR HEAVEN IS PERFECTION AND ONLY JESUS (THE SON OF GOD/GOD IN THE FLESH) LIVED THAT PERFECT LIFE! HE LAID DOWN HIS LIFE & TOOK THE WRATH OF THE FATHER ON THE CROSS FOR YOUR SINS! GOD IS JUST SO HE MUST PUNISH SIN & HE IS HOLY SO NO SIN CAN ENTER HIS KINGDOM OF HEAVEN. IF YOU ARE IN CHRIST ON JUDGEMENT DAY GOD WILL SEE YOU AS HIS PERFECT SON (SINLESS SINCE YOUR SINS ARE COVERED BY JESUS' OFFERING). YOU CAN ALSO CHOOSE TO REJECT JESUS' GIFT/SACRIFICE & PAY FOR YOUR OWN SIN WITH DEATH (HELL) BUT THAT SEEMS PRETTY FOOLISH! GOD SEES & HEARS EVERYTHING YOU HAVE SAID & DONE. YOU WONT WIN AN ARGUMENT WITH HIM & YOU CANT DEFEND ANY OF YOUR SINS TO HIM. YOU'RE NOT A GOOD PERSON, I'M NOT A GOOD PERSON... ONLY GOD IS GOOD! WE'RE ALL GUILTY WITHOUT ACCEPTING JESUS' SACRIFICE FOR OUR SINS! MUHAMMAD DIDN'T DIE FOR YOUR SINS, BUDDHA DIDN'T DIE FOR YOUR SINS, NO PASTOR/NO PRIEST/NO SAINT/NO ANCESTOR DIED FOR YOUR SINS, MARY DIDN'T, THE POPE DIDN'T EITHER, NO IDOLS OR FALSE gods DIED FOR YOUR SINS, NO MUSICIAN OR CELEBRITY DIED FOR YOUR SINS, NO INFLUENCER OR KZbin STAR DIED FOR YOUR SINS, NO SCIENTIST OR POLITICIAN DIED FOR YOUR SINS, NO ATHLETE OR ACTOR DIED FOR YOUR SINS! STOP IDOLIZING & WORSHIPING THESE PEOPLE! JESUS CHRIST ALONE DIED FOR YOUR SINS & WAS RESURRECTED FROM THE GRAVE! HE IS ALIVE & COMING BACK VERY VERY SOON WITH JUDGEMENT (THESE ARE END TIMES)! PREPARE YOURSELVES, TURN FROM SIN & RUN TO JESUS! HE KNOWS YOUR PAIN & TROUBLES, HE WANTS TO HEAL & RESTORE YOU! TALK TO HIM LIKE A BEST FRIEND! ASK HIM TO REVEAL HIMSELF TO YOU & HELP YOU TO BELIEVE IF YOU DOUBT! DON'T WAIT TO CRY OUT! NO ONE IS PROMISED TOMORROW! HE LONGS FOR YOU TO INVITE HIM IN, HE LOVES YOU MORE THAN ANY PERSON EVER COULD, HE CREATED YOU! Jesus answered, “I am the way and the truth and the life. No one comes to the Father except through me."-John 14:6 "But whosoever shall deny me before men, him will I also deny before my Father which is in heaven."-Matthew 10:33 “For the wages of sin is death (hell), but the gift of God is eternal life in Christ Jesus our Lord”-Romans 6:23

[@ReddCinema]

Your consistency and quality of content never disappoints! ❤

[@shahan484]

Eww bot 🤮🤮🤮🤮🤮 200 views on videos🤮🤮🤮

[@YeahImMan116]

@Alysra [Toxic Squad] go away

[@believeinjesus6972]

Repent to Jesus Christ “Let us then approach God’s throne of grace with confidence, so that we may receive mercy and find grace to help us in our time of need.” ‭‭Hebrews‬ ‭4:16‬ ‭NIV‬‬

[@divinedragon17]

@@believeinjesus6972 why casting spell here

[@kylieware9320]

😄

[@jamesheinz6325]

Great upload, thank you for the time and research.

[@sheninfrancis3822]

That transition from the Topic to the Sponsor (Brilliant) was impeccable!

[@erickfalcon1972]

I usually don't comment on KZbin but great video. Please make more videos that go into technical depth like this one.

[@truvc]

I would love to learn about rotating-detonation engines! And what kinds of possibilities they will unlock for aerospace.

[@ansleylobo8917]

I second this

[@TheGreatSeraphim]

If we had some kind of pre-launch slingshot like a railgun of sorts we could minimize the fuel load considerably as a massive amount of fuel is spent in the first few seconds just to get it moving. Getting it moving faster sooner means they can also make the bell more efficient by gearing it towards higher altitudes further reducing fuel load. Not to mention the additional fuel dedicated to lift that startup fuel.

[@ronjon7942]

Good point, it would be interesting to see a plot of change in mass or weight vs velocity, or vs thrust, or even time. I bet the weight of that startup fuel you mentioned would be staggering.

[@jocassid1]

Currently listening to the audio book version of "Ignition". Has a lot of very entertaining stories about the development of rocket fuels and oxidizers

[@ScottMurrayBestFamilyCars]

Geezuz I love this channel. Inspires me to make sure my kids pay attention to STEM when they reach big school. Great work, as always, Brian and team.

[@srijantiwari8152]

I was looking for something to watch and then I saw the notification of this🤘

[@CosmicShieldMaiden]

Same.

[@davesvoboda2785]

One thing to point out about the various fuels is how temperature compatible are the propellent and LOX. Liquid hydrogen is so cold that it will freeze LOX to a slush if there's a common wall. So even the "common dome" needs to be insulated. That decreases the Isp of hydrolox. For Falcon9, the kerosene is chilled to close to LOX temperature. And liquid methane has a similar temperature to LOX, for simple, light fuel tanks.

[@toxified3937]

Thanks for your ''Inspiration'' i'm pretty sure we need it these days

[@Fenthule]

As soon as I saw the RWGSR+ Sebatier reaction pop up I noticed that excess carbon immediately. Imagine if there was a way we could strip it, and just lay them out like a printer - essentially printing sheets of graphene. Oohhhhhh myyy. Here's your methane for fuel, your oxygen for breathing, some graphene for building materials, water for drinking. I should ask my chemical engineer buddy about this lol

[@mitchstilborn]

The thrust-time graph looks almost exactly the same as a stress-strain diagram for a strongly strain-hardening steel

[@huwzebediahthomas9193]

What percentage of carbon and other bits? There are new elements out there to be made you know? Super light, super strong.

[@mitchstilborn]

@@huwzebediahthomas9193 I wasn’t thinking of one in particular, sorry. Just the general shape of it; steel elastic region, long, upwards strain-hardening region.

[@huwzebediahthomas9193]

@@mitchstilborn Yes I know. Great research is being done to make new elements - amazing what can be made with extreme low and high temperatures, and they are very stable at those temperatures. But fall to electrons and protons at room temperature though. 🙂

[@Acein3055]

Thanks for the well done video. What I liked most about this video is that it wasn't degraded by having to look at someone's face presenting this video.

[@abhiram118]

lovely explaining keep it up

[@kstricl]

110% on closing the carbon cycle. Storage of energy by means of liquid production will be essential long term. Cheap hydrogen production is something the oil industry can actually help with; in situ hydrogen production (leaving the carbon trapped down hole) is something that can be done, ideally powered by renewables, and pipelines could be retrofitted to allow transport. We just need the will to do it.

[@JamesGriffinT]

Finding "the will" is the hardest part of the equation, it requires good governance, building concensus, effective politicians and buy-in from both investors and the public. If it was so easy then we could have already insulated our homes, reduced our meat consumption, bought smaller cars to drive on cyclist friendly roads. We have most of the answers already, the faith in future, uncertain and often specious technological solutions can only hold us back from taking mundane but necessary steps now. I know this attitude is less exciting, less aspirational and makes for less interesting KZbin videos (though "Technology Connections" might beg to differ), but it does provide a practical way forward.

[@MUSTASCH1O]

It is not just a matter of having the will to build the infrastructure. The technologies for cost effective hydrogen production, though improving, are still at the demonstration stage at best. Effort must continue on the R&D front, and government can support that. This is perhaps one area where our will must be focused right now. Gen IV nuclear reactors will also be so safe that I see no distinction between them and renewables. We should have no preference between the two; they will both have their contributions to give.

[@theultimatereductionist7592]

@@JamesGriffinT Nothing stopping 99% of people going vegan today. We millions of vegans have been vegan for centuries. People for the Ethical Treatment of Animals (PETA) has prevented the needless breeding and murder of a billion animals by getting millions to go vegan.

[@tomkelly8827]

Hydrogen is too large and reactive to be a fuel. In order to transport and use it, it needs to be bonded to something like a carbon atom. Otherwise the metals and plastics used as pipelines and storage containers would leak right away. It is not a matter of will, it is a matter of chemistry. It makes no sense chemically or from an energy efficiency standpoint. Hydrogen is too large and volatile on its own

[@xponen]

​@@tomkelly8827 regardless of the problem, Hydrogen is the main ingredient for producing Methane.

[@jakob2045]

Please look into the reaction equations again. 9:00, 11:00 Between 4H2 and 2O2 belongs a plus and the plus sign in front of line two is not necessary (same for 11:45). The 2 in CO2 in the third line needs to be subscript. There are missing many subscript 2’s as well. 12:30 It’s supposed to be 3CO2. I studied chemistry so im automatic in such things. :D Besides that i liked the video quite a lot.

[@jakob2045]

I dont get what you wanted to say with the reaction equation under “Hydrogen Transport” at 11:45… its the same like on the left side only with less electrolysis. Im confused

[@skchan2]

You are right, and the equation is not balance. 11:45 typo on both side 2nd equation, should be 4H2 instead of 4H. (Left side 4H, right side total 8H)

[@jamie0]

You make several referencs to the sooty exhaust of the Saturn V F1 engines. I wonder if the appearance that you're referring to is more about the raw fuel that was injected at the head of the nozel to create a "cool" eveporative barrier between the intensely hot exhaust and the inner walls of the novel. That fuel would not burn completely. They actually went to great lengths to make sure that the RP1 fuel and liguid oxygen mixture burned efficiently and consistently. Without that you get violent feed back pressure/thrust changes called pogo'ing that would damage the rocket structure.

[@davidhagemann7037]

this video earned you a sub; absolutely useful info, thanks!

[@BusterBuizel]

Wait... So Highfleet’s worldbuilding actually makes sense using liquid compressed methane to power massive airships? And the fact that the Co2 that is expelled by thrusters into the atmosphere can be recondensed and refined back into liquid methane? HOLY CRAP THATS NEAT

[@AncapistanVan]

pls explain?

[@abelknecht4943]

CO2 can always be brought back to methane, but thermodynamics say that you need to put at least the same amount of energy back into the reaction. engineering says you need more energy. This process is only viable if the energy is from renewable (non CO2 emitting) sources and the original process must emit CO2, such as cement production.

[@BusterBuizel]

@@abelknecht4943 seeing as how Highfleets world features a nuclear reactor the size of a city and hundreds of thousand+ ton airships outputting enough rocket thrust to instantly insulate a small planetoid with greenhouse emissions I still think it’s pretty neat on the worldbuilding how this all fits together

[@kirans6976]

Now you are talking. I like to watch this kind of engineering talks rather than some kind of weapon engineering

[@1zebbe3]

@Jan Krixtian especially when being used??? How can you even say that in this time of war?

[@1zebbe3]

@Jan Krixtian how about not talking about it like you enjoy it for starters. I am not saying you shouldn‘t defend yourself if necessary.

[@dozer5069]

Some really good editing here.. nice.

[@437thx1138]

nice vid. enjoyed the chemistry too

[@mikefischbein3230]

"... and if there's one thing I know about, it's corruption of a god given ability to do stuff with rockets." - Wernher von Braun

[@deeas6518]

"He aimed for the stars, but sometimes hit London"

[@genghisthegreat2034]

Werner, remember Peënemunde

[@slyseal2091]

Me and the boys on our way to starve 4 billion people because Fritz Haber made some stink bombs

[@pioneer_1148]

The variety of kerosene used in US rockets is called RP-1 (the russiana have something called T-1 that is similar) It's far more refined than regular kerosene with lower sulphur, less alkenes and a tighter distillation range to give a higher quality fuel with more predictable behaviour.

[@rocketsocks]

Mars actually has ice everywhere, not just at the poles. Almost everywhere has a sub-surface permafrost layer. Down to mid latitudes this is pretty shallow, just a meter under the surface, at lower latitudes it's probably deeper and somewhat more sparse. Some regions include sub-surface glaciers of high water ice concentration, as shallow as a meter below ground, and these exist even at mid latitudes in many locations. Seeking a location to site a Martian colony one would want to look for easy access to sub-surface glaciers.

[@morkovija]

Top quality content, once again here lads. Thank you

[@matteofuriabonanomi1807]

good video sir, really interesting. just one clarification from a pedant chemist: at 9:04 you say that 4 moles of hydrogen are used, but if you look closely you can see that that hydrogen has no "2" at his pedice, hence I suggest you to correct it because if you leave it like this it seem like you're using radical hydrogen. also I don't understand why you didn't add the plus sign (+) in between oxygen and hydrogen generated trough electrolysis in the same set of equations; finally the CO2 at the bottom equation should have the 2 at pedice since it indicates the fact that the carbon is linked to two oxygens. as a general rule for chemistry equations: numbers in front of formulas are normal and those indicates the number of molecules obtained, and numbers in the formulas of in front of formulas indicate how many atoms are included in that molecule hence are write smaller ( pedice). if you need a clarification contact me freely. have a goo day.

[@SpaceStick]

Hey this is what I’m learning about in my chemistry class. Just thought it was cool

[@SirThreepio]

Very nice presentation. Could you make a follow-up video with ways to process Mars rock into H2, O2 and metals? Excuse my lack of chemistry - but is there a way to do something with CO?

[@aninditabasak7694]

Nothing to do with carbon monoxide or CO

[@unobombers]

8:10 looks like a good atmosphere for steel welding :D

[@Advoc8te4Truth]

The fact that Man successfully flew to the Moon, landed and then flew back is just mind bogglingly incredible when you look back and analyse the technogy available. I mean seriously a modern Smart Phone has more compute performance than the IBM Mainframes available at the time.

[@mareksykora779]

Actually those guys in Apollo spaceship were trained the way that they could return back even when the computers stop working. They learned navigation with sextant and stars to specify their actual position and orientation. They could calculate the right moment of the engines just with paper and pencil and meassure its running interval just by stopwatch. All manual stearing. Just read "The story of the Apollo sextant".

[@Advoc8te4Truth]

@@mareksykora779 Nowadays if you said can you use a Sextant people would think it was a sex toy.

[@mareksykora779]

@@Advoc8te4Truth Yes, people are turning to be more and more animal nowadays. Their interest is just food, sex and relax.

[@davidelang]

one advantage of methane that you missed is that for every other fuel combination you need to insulate between the lox and the fuel or one will freeze the other. Methane doesn't need this. It's also worth noting that SpaceX isn't the only company working on methane rockets, there are several others doing so.

[@topsecret1837]

The thing about methane is even compared to other paraffins like Propane, Butane and higher up, methane has to be just below LOX’s boiling point but just above the fuel’s melting point. Whereas with Ethane and Propane they boil much higher than methane but freeze at lower temperatures. Butane freezes at considerably warmer temperatures as you’d expect but Propane, being denser than methane yet more common than Ethane while being immensely more storable, would make a practical Rocket fuel.

[@topsecret1837]

So in short: Methane, hands down is the best performing fuel when large scale multiplanetary missions are the goal, with hydrogen being the best performing overall for more distant missions requiring more efficiency. Propane, however is a close third, being highly practical for getting vehicles to orbit from planetary bodies of gravity higher than the moon due to better density than hydrogen or methane, but with in-between specific impulse to kerosene and methane and considerably more difficult to manufacture sustainably.

[@davidelang]

@@topsecret1837 Is propane more energy dense for it's mass? I know I've seen videos about one company (IIRC in the UK) working to build a propane powered rocket, but I thought the video talked about propane having less energy than methane

[@davidelang]

@@topsecret1837 actually, hydrogen isn't the best for deep space missions, for those you want an ion drive. Once you get to orbit you no longer need the high thrust that chemical propellants give you, and what matters more is specific impulse (modified to take into account the tank mass, not just the reaction mass) Hydrolox is pretty good, but still only about half of what an ion drive can produce (not accounting for power supply and tank mass) and nuclear thermal engines can be even higher (same caviot applying)

[@imconsequetau5275]

@@davidelang In a sense, the video does mention how little insulation is needed at the shared LOX/methane bulkhead. For Hydrogen they didn't share the bulkhead.

[@patrickwrightson2072]

Thank you for continuing to cover SpaceX and their amazing progress. It’s very appreciated.

[@2nd3rd1st]

Successful carbon capture technology doesn't only hinge on reduced cost but more importantly on the high energy requirements. CCS is very power intensive and using fossil fuel power would naturally ruin CCS efficiency, whereas building out renewable power to meet our energy needs would quickly make CCS redundant. In both cases CCS as a bridge technology is only useful to the industries that promote it but not for actual climate change mitigation.

[@clarencehopkins7832]

Excellent stuff bro

[@PetesGuide]

Best damned explanation of specific impulse I’ve ever heard. I’d like to underscore how high a compliment that is: I was lucky enough to spend more time hanging out with a physicist/rocket scientist (and great communicator) than my own dad-one who had Werner on speed dial and had design oversight over all the Apollo electronics. Keep up the awesome work!

[@VecheslavNovikov]

Wouldn't it be simpler to say that specific impulse is basically exhaust velocity? (divided by g for reasons). Basically, the faster you yeet burnt fuel out the back of the thing, the faster the thing can go on the same amount of fuel.

[@jeromethiel4323]

Amazing! Nice to see a science channel show WHY we should spend money on science. People complained about the Apollo program, not realizing how many scientific and engineering advancements we use every day today were the direct result of that expenditure of money. You almost always get more back from the spending on science, than from any other thing.

[@zimriel]

It was mostly black people at the time who complained. "Whitey On The Moon". Taxpayers didn't complain.

[@mostlynew]

Best explanation of Methane as the rocket fuel of choice

[@willythemailboy2]

I wonder if other very small hydrocarbons have been investigated - ethane or ethene for example. Even acetylene/acetone mix. They'd fall between methane and kerosene in terms of storage and stoichiometry. Or perhaps anhydrous ammonia.

[@Dochdochdoch01]

Brilliant is not for engineers. It's for upcoming engineers. I tried it with your recommendations. I could easily solve many courses without any issue.

[@machinaexcarne]

"Brilliant" cannot educate. They can make you feel like you've gone crazy. You can get you answers right, but they will tell you they're not, only for them to come back WEEKS later, only to offer a measly corporate apology for all the possible damage they could've done. And all thet happened in the demo before you even pay them. I doubt they're doing it any better on their paid program.

[@saumyacow4435]

At 14:14 it speaks of using the Sabatier process in creating storable energy. I don't get this. If you're starting point is hydrogen (presumably via electrolysis) you lose more energy creating liquid methane than creating liquid hydrogen. Liquid methane might find a use in things like ships (due to easier storage), but for grid scale energy storage, where you've got room for the insulation, liquid hydrogen probably wins.

[@pocarski]

Insulation is not the way. For every liquid, its boiling point increases with external pressure. If stored in a strong enough vessel, a liquified gas can keep itself liquid through its own vapor pressure. For example, lighter fluid is actually a gas under normal conditions, but the body of a lighter is strong enough to contain the vapor pressure and keep the fuel liquid. The lower the boiling point, the more pressure is needed to keep the liquid from boiling at room temperature. Liquid methane has a much higher boiling point than hydrogen, so it's not unfeasible to store it in high pressure tanks with minimal insulation. Besides, its molecules are a lot larger than hydrogen, so methane-tight storage tanks are much easier to make than hydrogen-tight ones; as was mentioned in the video, methane has a lot more energy per volume as a liquid, so it's more space efficient as well. You're right that it is theoretically more energy efficient to store hydrogen directly instead of methane, but practically storing (and let alone transporting) one is way easier than the other.

[@saumyacow4435]

@@pocarski Yeah, but to keep liquid hydrogen a liquid, even at liquid nitrogen temperature, requires extreme pressure (not going to look it up right now, but its huge). The point about hydrogen is not transporting it. Rather you liquefy it on site and convert it back to electricity on site. Likewise if you need hydrogen for steel making, you make it on site and use it on site. Methane could have its uses, but ammonia is denser, easier to store and is being promoted as a fuel for things like ships.

[@benholroyd5221]

Is energy efficiency the correct metric though? If you have wind turbines turning and not enough demand to soak that up, the rest would be going to waste. From that pov an inefficient process that results in an easier to store fuel isn't necessarily a bad thing. If you're storing fuel over multi year periods cheapness and ease of storage likely wins over efficiency of something that was going to waste anyway.

[@pocarski]

@@saumyacow4435 I've looked it up, both of us forgot about supercritical fluids. If you get a hot enough gas under high enough pressure, it becomes a fluid that blends together properties of liquid and gas. Both methane and hydrogen are supercritical at room temperature, so this entire argument is moot because both of them get properties so cursed that I couldn't find a single formula that describes them. Hydrogen's critical pressure is 13 atmospheres, while methane's is around 45. I'm not entirely sure what that means for storing them, because I have zero idea about what happens to pressure vs density when a gas is hotter than its critical temperature.

[@saumyacow4435]

@@pocarski Yeah, I looked it up and came to that conclusion. I think hydrogen would be supercritical even at liquid nitrogen temperature and worse, it would be fairly low density. Even so, liquid hydrogen at atmospheric pressure has its uses and I suspect there are ways to recover some of the energy used in liquefying it.

[@paladin0654]

Excellent run down. Recommendation: use the conjunction "and" instead of "but" if you're contrasting two statements rather than adding on.

[@user-cd4bx6uq1y]

Having slept on the space news for the last 3 years, I have no idea how exactly does having larger fuel tank volume negate thrust efficiency and why do we care about it negating whatever it negates

[@lazarus2691]

Larger tanks are heavier because they're made of more material. Pushing more weight means the engines have to work harder, which negates the higher efficiency of the fuel.

[@user-tf7je1tf4q]

I think the chemical equations at 9:00 (& repeated elsewhere in the video) should be 4(H2O) --> 4(H2) + 2(O2) 4(H2) + (CO2) --> 2(H2O) + (CH4) (Using parentheses because I can't do subscripts here, so treat all numbers inside parentheses as subscripts.) Note 2nd equation is shown correctly at 8:55.

[@2hedz77]

@12:17 did you find an error in the final eqn for the 'Hydrogen Transport' final eqn too? Requiring 2 moles O2 for every 1 of CH4), I get: 5CO2 + 4H2 -> 4CO + 2H2O +CH4 + 2O2 compared to video: 3CO2 + 6H2 -> CH4 + 2CO + 4H2O . Both eqns are balanced...but since the product oxygen (needed for subsequent combustion) is omitted in the products I think the molar coefficients in the video are in error. Is this correct?

[@user-tf7je1tf4q]

@@2hedz77 all equations @12:17(RWGSR + SR) are balanced. But the formulas at bottom keep changing until 12:31, & I do see a problem there. 2 C atoms on left, but 3 C on right 4 oxygen atoms on left, but 6 oxygen on right 12 H atoms on left, 12 H on right, but that will have probably to change when the others are fixed. . Is that what you mean by final equation?

[@2hedz77]

You are right! Yes @12:31 ... total mess. But what I am saying is that @12:17 he did not include oxygen in the products. Therefore even though the equation is balanced it is wrong because one of the products is totally missed! Anyway...what a mess of a video. Not sure what happened.

[@paniniman6524]

Once you get the methane, you can continue to reuse the water made from the methane making process. A one time shipment of water or hydrogen may be viable as it cancels the need to build mining infrastructure on Mars when resources are scarce.

[@rolfbjorn9937]

A multitude of tanker Starship, perhaps purpose built just for this specific preparation mission, could bring not only the equipment necessary, but mainly a literal ship load of water, or if very courageous or stupid, HTP, our good old friend Hydrogen Peroxide H2O2.

[@paniniman6524]

@@rolfbjorn9937 peroxide tends to be extremely heavy for the amount of hydrogen it brings. Water is already extremely overweight. Problem with transporting pure hydrogen is leaks. It takes months for hydrogen to ship, and it's not guaranteed a respectable amount of hydrogen is delivered. But if you plan to also bring oxygen to mars, by all means, go ahead, but oxygen is way easier to extract on mars, and doesn't require too much infrastructure.

[@Wombbatts]

I watched Apollo 11 take off in person. I was seven, I was standing between Bob Hope and Robert Goulet, Bob Hope had his hand on my shoulder. The noise was amazing, like the rip in the crack of thunder, that was continuous. You could feel it in your chest.

[@dogbox2290]

Brilliant☀️🌴 love your work

[@iamjoris]

Great video, as always! I would definitely mention synthesising fuel on Mars in the title. If I had seen that, I would have immediately clicked (instead of having to convince myself to click because I know your videos are good stuff).

[@kitnaylor7267]

1:10 this is a gross oversimplification. A liquid hydrogen first stage was considered, and would have been feasible to build - and would have resulted in the Saturn V weighing only 2/3 what it did. The reason they didn't go with it wasn't tank size, it was that liquid hydrogen produces much lower *thrust* than kerosene, so building a powerful enough first stage engines would have been more challenging.

[@xponen]

can use booster like they did with the Space Shuttle. Solid fuel has the highest thrust ever so they are often used as a strapped-on boosters for lots of rockets.

[@angrymokyuu9475]

​@@xponen I don't think that solid fuel rockets were where they needed to be at the time, plus the US had little experience with the concept at the time the Saturn V was designed(though it's noteworthy that the Soviet N-1 also lacked boosters, despite their experience with them).

[@kitnaylor7267]

@@angrymokyuu9475 The largest ever solid rocket motor was actually fired in 1965 and 1966 (weighing about 850T, compared to the 600T for the shuttle). These were meant to be alternative first stages for the Saturn 1B, but were never flown... or even removed from the test stand after firing, they're still there.

[@enuskolada6618]

Wondered about acetylene and that big old high energy triple bond. Nuh- 1300 kJ·mol−1 vs 891 for methane. c. 50% greater molar energy density, but each molecule nearly twice the weight. Couldn't find enough information on density, but it looks like there might be difficulty in the kJ.kg-1 area. Also, I wonder what the synthesis and storage dramas might be? I did see some mention of it being unstable.

[@caseyjones6425]

Professor Daniel Nocera from MIT developed a catalyst with a botanist from England to break down water to oxygen and hydrogen, easily, efficiently and cheaply, modeled after a microorganism from the ocean, using solar panels for the electrical energy source. He called it personalized energy. A quart of water could power a typical house in the US and the water source doesn't have to be ultra pure, although after the hydrogen is passed through a fuel cell, recombining with oxygen, pure water results along with electricity. A small unit on board a ship to Mars would make it very easy to obtain hydrogen and oxygen.

[@sebastianucero7535]

Is always shocking to hear "Dr. Strangelove"... sorry, Mr. von Braun. The man that opened the skies to mankind

[@jtgd]

“My Fuhrer! I can walk!”

[@saumyacow4435]

"I only send them up. I don't care where they come down. That's not my department, says Wernher Von Braun"....

[@mbgdemon]

@@saumyacow4435 In German, in English, I know how to count down... Und I'm learning Chinese, says Wernher von Braun

[@saumyacow4435]

@@mbgdemon Good.. you know the reference :)

[@nicholasklangos9704]

Great video! Your reason for the importance of NASA and other space research science etc is spot on and a constant justifiable positive argument I have had for decades with those that ask those questions and don’t understand. Most people don’t know all the benefits that have come from those decades of science in their everyday lives, medical science one of the biggest, too many to name. Go space X! And other commercial ventures!!

[@arthurwagar6224]

Thanks for good stuff.

[@johnwang9914]

Note that you can also produce equivalents to kerosene from the CO₂ and water of Mars by producing carbon monoxide and hydrogen gas and then using the Fischer Tropsch synthesis which we already use in our refineries to produce synthetic kerosene.