People think Apollo didn't have enough fuel to get to the moon?
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- čas přidán 19. 12. 2023
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#globe #science #flatearth #apollo - Věda a technologie
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Probably the best Segway's to ads on CZcams, always enjoy trying to predict when it's about to happen 😆
Any plans for the 100k subscribers? Looks like you are pretty close.
Cheers. czcams.com/video/H41QJEpXI0o/video.htmlsi=nCin0SP1w-H5kC8P
Very interesting thank you, learning a lot. I loved your video on the iss raw photos. Keep up the good work
The fact that NASA has zero telemetry data for any of the moon missions should be all the evidence or lack there of that you need to know that the moon missions never happened
Everything you are describing is theoretical 😢
Steps to become a Moon landing denier:
1. Have a skeptical mindset. This is a good thing.
2. Ask lots of questions. This is a good thing.
3. When your questions are answered a million times, hold your hands over your ears and yell "nuh uh".
The process is just like flat earthers -
1. Come to you conclusion (in this case fake moon landings)
2. Ignore everything that contradicts you conclusion and claim it's fake.
That's it.
Y'all forgot the following step:
"This is actually very simple to understand and not rocket science, everyone must be lying, or being lied to"
It’s healthy to ask questions and try to verify. It’s not healthy to dismiss the explanations because they don’t adhere to a pre-conceived idea.
That's conspiracy 101 basically.
What these people have is not a skeptical mindset. They have an overpowering irrational fear of legitimate information and sources.
Fuel management is such a hard thing to do properly, even in a sim like KSP. It truly is rocket science. Major props to those Apollo scientists that got it right and allowed the missions to succeed.
Indeed. Sometimes counter-intuitive, like how you aim your engine 'away' from your desired docking target to get into a lower orbit, with a shorter period to 'catch up' to the target. And how sometimes you wait until at perigee or apogee before firing, to use the least amount of fuel to change your orbit.
With slide-rules.
@kstricl
Understanding the mathematics of CHANGE is all that is needed.
Calculus!
Newton and Liebnitz are the real heroes and geniuses.
@@chrismaverick9828 No, they had access to big mainframe computers to do the number crunching.
Yeah I saw an ad for KSP2 and decided to play with KSP and try and 'beat' it before moving to the new one (which according to the forums and discussions online, I may wait a little while until all the bugs are worked out). But it's an amazing and fun game and his points are very relevant to that game! It's super addicting and my poor Kerbels :-(
Spaceflight isn't flying as much as it's falling with style.
Nice 🙂
with lots of hot particles being thrown out the back at several times the speed of sound
@@yeethan1094 : That's only for some few minutes while falling last sometimes years.
@@ThomasKunderayes, I am aware.
would it be better to say: punctuated by brief periods of throwing hot particles out the back at hypersonic velocities?
@@yeethan1094 : I would agree more 🙂
As a physicist familiar with orbital mechanics this explanation is both accurate and easy to understand. Good job!
As a guy who play Kerbal Space Program, I agree
@@thedogmagician1050 As a guy who plays Orbiter, I concur.
Well, it would be much clearer if it used standard measurement units. I gave up after watching less than a half of it. It isn’t probably addressed to an international audience.
@@giorgiobarchiesi5003 it just takes minimal conversion, this should be no problem for anyone willing to spend five minutes looking up the different units of measurement and comparing them.
@@jochenstacker7448 Yes, that’s totally true, but here’s my point of view: I’m doing the effort to listen to the video in a language that is not my mother language, and this is ok with me because for some reason English has become the standard language for international communication. I think it would be fair and polite if the other half of the effort, that is using international measurement units, would be done by the author. Possibly in conjunction with the imperial/american units. I’m an engineer, my job is doing computations. At least during my relax time I’d prefer not to. 😉
Making rocket science understandable isn't easy. Great job Dave!
What?! Isn’t it “Rocket Surgery”?! 🙄 And brain science …. 🤔
Ya make it easy , he can’t even explain the staged four foot jump. Grow up will you
Making up crap is easy, Dave is certainly good at making it appear as though It's real, too. It's not, of course, but great job, Dave. You're the Boss.
@@Tonyprice703 wow,...surprised that didn't get censored....to true .
The car on the hill example is a perfect, clear analogy which makes things so easy to understand. I have little hope for flat earthers, as they will stick their fingers in their ears and deliberately avoid the truth, but your videos are excellent for anyone who’s willing to learn.
I agree, the hill should be rounded with a gradually decreasing climb angle instead of a point at the top but it is a good analogy.
I have read several sci-fi authors that describe the Earth and Moon system like being at the top and bottom of a hill. Like having mines on the Moon that can easily send ore payloads back to Earth, because all it takes it a little push to get them over that small gravitational hill, before they fall the rest of the way down the mountain on their own. But getting supplies from Earth to the Moon is really expensive, because you have to shove it all the way up that giant gravitational mountain before it finally falls that last little bit on its own.
33% All true, in fact I tried to only hear every 3rd word and that made it easy to conceptualize the flat earth mind set. Marvelous!
i think we need an a word for flat beliewers ... like flat government beliewers :P or flat government faithers or flat politics or flat nasa believers etc. who thing that world is made of flat integers... but the problem is politics governments and goods bads eils has floating points as definitions and they are not constants :D
Dave lost all the flat earthers 20 seconds in. But I agree that the car on the hill was brilliant.
And for Apollo 11, the person that wrote the book (literally) on orbital mechanics was onboard.
And he wrote it before ever knowing he’d go up there one day.
Thats the reason he’s DR. Buzz Aldrin.
To be fair, his thesis was on orbital rendezvous between two manned craft. All of the orbital mechanics required to get the upper stages on route for TLI were proposed around 10 years before Dr. Rendezvous (Buzz Aldrin) had been conceived. That being said, the theories from his thesis were used for the docking of the landing module and CSM on-route to the moon, when the lander docks to the top of the CSM. And again when the ascent stage of the lander docks with the CSM.
We have Hermann Oberth to thank for much of the early study into orbital mechanics for space craft. But Kepler proposed many of the foundational theories on 2-body orbital mechanics hundreds of years prior. Shit, Newton was already aware of the N-body problem by the middle of the 17th century. Much of this hasn't been a mystery for us for centuries. Which is part of why it's so laughable that people still fall for these conspiracies.
Yup. Aldrin wrote his PhD thesis on orbital rendezvous at MIT on this very subject and got to use it on Gemini 12.
I will never stop being fascinated by people calling themselves names like "TheTruthandnothingelse", who insert themselves into discussions about orbital mechanics, while basically failing to understand that for a rock that you throw up in the air (or a "vacum"), you dont need fuel for it slow down and eventually return to the ground. This isnt even one of the many counter-intuitive parts of orbital mechanics, but is very much in-line with the experiences every child (should) make.
Really... Never kicked a ball as high as you could, as a kid? What was its speed at the highest point, every single time? And what would its speed be as it hit the ground again (roughly)? This is so freaking basic...
it's pretty much a guarantee that if someone feels the need to put "truth" in their name, they are pathological liars
That is a very good simple example and visualization that can be used to explain this to a child/flerfer. Thank you.
@@victorfinberg8595 There are plenty of grifters that know they are grifting but see it as an easy scam.
You can fix ignorance, but you can't fix stupid. Stupid is not allowing science, logic and reason be a part of your thinking processes. It's an insult to Western Civilization that these clueless clowns are allowed to vote.
@@victorfinberg8595 It's all basically about an inferiority complex.
This is one of the best explainers about orbits and orbital speed I’ve ever seen. The animations are cool and simple to understand and you are so good in breaking down complex topics for all of us to understand (except flerfers,they don’t want to understand). Very well done 👍
far from it. this is dumbing it down for flerfs and moonlanding deniers, though neglecting and underestimating their capacity to avoid all thinking entirely. There are much more thorough explanatory videos out there, chanels that don't directly deal in flerf-debunking (in a way, even debunking flerfs gives them certain importance, which is unnecessary and validates them indirectly..)
@@e.h.5849 you can even study it in universities,get your masters degree and phds,then you have a much more thorough understanding than watching videos out there.
@@e.h.5849 I completely disagree. This was a very good depiction of how it works for the layman.
@@paulslund1 Thank you, I completely agree with you.
Pay no attention to the 🤡. You are absolutely correct. I've watched science shows for decades and this IS the best and most intuitive visual representations of the dynamics involved. Ya know, for those of us NOT studying to become an astrophysicist 😆
There's a passage in Michael Collins' book in which, as Capcom for Apollo 8 in mission control, he notes the exact second that the spacecraft crossed over from Earth's gravitational influence to that of the moon's, and that this was the first moment in human history that people crossed the threshold into the gravity of another celestial body.
Outstanding book!
I think that's in Andrew Chaikin's book too. It's a profound thought.
Baaaahaaahaaa what a joke. Collins is a lying criminal, he knows that. The moon men fraudsters, all 3 of them should be jailed.
@@Black-CircleYou’re either misguided or funny…but you are not both.
@@Black-Circle they're never going there, its been postponed for 30 years now. Every president from Carter onward said it'll be done in the next 5 years including the Don, but the Van Allen belts will still be there in a million years and NASA know this. They're even admitting this openly now, by saying they can't recreate the technology. Now you have to remember,ber that nowhere in history, never, has technology ever gone backwards. Never. Only with Apollo.
However, the discussion is over with AI calling the Chinese rover photos genuine but Apollo's not. Check that, moon men are finished.
America's most advanced neural AI has called it.
3:43 For those wondering why it's called apoapsis rather than the more familiar term of apogee, the '-gee' part refers exclusively to a spacecraft's relationship to planet Earth.
Other astronomical bodies have their own exclusively specific terms (-lune for the Moon, -helion for the Sun, -jove for Jupiter, etc).
But what about a spaceship going to an unexplored star system with no named planets? Well, the term -apsis is simply the generic name to be used.
Space crafts do not exist and planet earth does not exist because earth is flat still and motionless Einstein proved it not once but twice and earth is covered by a dome
In thise case it is perfectly valid to call the point the CM is headed for after its TLI burn the Apogee, even if the later influence of the moon alters the crafts course and it dose not pass through that exact point. It's arguable that even the point at the back side of the moon where the Insertion burn occours as the Apogee as well because it's the maximum distance from Earth that is reached. One switches to Apolune and Perelune only once in orbit of the moon, so after the insertion burn their would be a highest and lowest altitude of the lunar orbit defining thouse points.
@@kennethferland5579 space starts at 62 miles high so says NASA which is the only thing NASA has ever been truthful about astronauts get their astronaut wings at 50 milles high knowing they will never go above 62 miles high nothing has ever been to space because rockets can not produce thrust in a vacuum so the rocket just falls back down at the 62 mile mark
@@kennethferland5579 nothing has ever been to space which starts at 62 miles high so says NASA much less the back side or front side of the moon rockets can not produce thrust in a vacuum real simple real easy to understand and face the truth rockets fall back down at the 62 mile mark
Yeah idk why the whole "apo-x" family of words still exist, periapsis and apoapsis are just much cleaner.
I've always loved the fact that flerfs fail to understand even basic concepts of physics, yet they think they can debunk the sum total of human knowledge.
yes, it just amazes me as well.
These are the same people that think the combined militaries of the world conspire to guard the "Great Ice Wall", which on their map, is so incredibly massive that it dwarfs all the enclosed land masses. It would take the combined effort of every single human on Earth to guard that massive area - and then there would be no one left to keep the secret from.
@@TokyoXtremey'know, I don't even get why they believe that the government is hiding something from them. If the earth was flat there would no reason to hide it. Y'know, it's really just that they have boring lives and they want to do believe they're doing goo
@@TokyoXtreme Geez ,man, you got me going: "Really? Ice Wall? haven't heard that" then Google into that insanity; yet compelling from a fictional / fantasy POV. The maps look fun. Maybe flat earthers do it just because it is more interesting (and less confusing than trying to understand the real world). Like people becoming fans and obsessed with say, Middle Earth, or Westeros, or D&D realms. I know, it isn't that harmless.
@@funkyjbass7762 It's the same ice wall that prevents all the ocean water from spilling out and falling off into space (or the heavenly waters, whatever). Others claim that the ice wall separates our realm from the other realms like Agartha, much in the way of classic LOTR. It does sound kind of cool in a fantasy universe, and that's why I have a soft spot for "hollow Earth", where those same lands can conceivably exist.
So many of these questions boil down to "I don't understand it, therefore it's impossible."
When did people quit having any humility when it comes to knowledge and edcation?
Donald Trump made being stupid a good thing.
Actually ALL of these questions are from ignorance of the science and how thing actually work.
@@swinde That's probably fair.
The Dunning-Kruger Effect is the cause in most cases.
The question actually boils down to how did humans so casually do this several times 50 years ago and still can't replicate it today even with all the technological advances.
I know the moon landing is real, I understand it. However people have a legitimate skepticism, you shouldn't ridicule them for that.
Let me ask you this. Do you personally understand the science and math behind the moon landing? If so did you before watching this video? If not then you're basically doing exactly what your comment suggested others are doing.
This is one of the best explanation of escape velocity and orbits of man made objects. While studying this topic for my undergrad I tried to explain to my friends this using the method you just did. You started out with the canon ignoring air resistance, gravity, friction, angular momentum, ect. Adding one in a time like a chef adds items to a soup. This is why all undergrad physics exam questions start with "ignoring friction/air resistance and gravity" and by the final you are calculating it all longing for the days of "ignore gravity".
as an 18 yr old college student, 40 yrs ago, my geology teacher claimed in the classroom that we did not go to the moon based on escape velocity. He says a rocket could not gain the momentum and thrust at take off from earth to push thru the gravitational pull. I asked him if he had seen the movie, 'Capricorn One'. "One of my students wrote the plot" he said facetiously....... 🤭
In college, I took three semesters of physics. In one of those classes, we had to do rough calculations of the physics involved in getting spacecraft from the Earth to the Moon. When you know how to make the calculations, it isn’t difficult to come up with the basic numbers. 35+ years later, I can’t do that kind of maths, but I could back then. It was a complicated thought-experiment, basically. This explanation here does a better job of explaining that thought-experiment than any professor ever did when I was in college!
I had similar physics class, but they were normally nice,and you had a constant mass, so you didn't have to worry about changing mass from fuel burn, and how that changes and complicates the calculations. NASA scientists did have to worry about that, and my TI-55 in 1982, probably had more computing power than the mainframes at NASA in 1968.
Hahahaha, a bit like NASA.
@@deanhall6045 you're so funny aren't you. To laugh at.
@@asneakychicken322 at least if I'm going to be funny I can back my points with facts. You're just a fckng troll. See ya.
@@georgeharris6851not to mention how many of their calculations were done with slide rules and brain power.
I learned to navigate jet cargo aircraft with a sextant (stuck through a port in the roof, time, a circular slide rule (Jensen CR3), a drafting compass, a gyro compass, and a sharp pencil (a sharp pencil line was 3 miles wide and a dull one over 5 miles wide on the charts we used).
Today, most people have no idea how to use those tools. But when their phones go dead, they won’t be able to find their way to the next town let alone across an ocean or to the moon.
This video reminds me of the old saying: "Orbital mechanics is the art of falling toward something and missing"
"the secret to flight is to throw yourself at the ground as hard as you can and miss."
the best description of freefall I've found.
Hitch Hikers' vibe there.... Didn't Dent Arthur Dent try flying once?
The moon landing deniers’ approach: throw whatever you can at the wall and hope something sticks.
i wonder what happens the day when nothing sticks.
They've been trying it for 50 years and haven't gotten anything to stick yet.
And pretend you didn't throw anything when it doesn't stick.
@@jootan91 That's the fun part, then you get to lie about what did/didn't stick and never have to prove your findings with facts or evidence.
I mean... Sh!t sticks... So that counts?
I remember I was 8 yrs old on my birthday, July 16 1969 when Apollo 11 lifted off. I watched it on a sunny morning on a little 13 inch black and white TV. I think that's all that was on the 4 channels we had, ABC CBS NBC and PBS. Walter Cronkite RIP.
I was lucky, my parents took me to watch Apollo XI launch in person. Loudest day of my life (9).
So excited watching that glorious Saturn V rocket lift skyward!
That image is forever burned into my mind!
I still have the commemorative coin depicting that event.
Nice! Even as a child, back in the 1960, I found that orbiting the earth, and that it was not really weightless, but "freefall" that also made perfect sense. The concept of traveling in a vacuum made perfect sense. No air, no resistance and why they travelled in zero g - no acceleration. The pull of gravity and the concept of aiming for where the moon would be and the getting into lunar orbit - and "burning" when necessary - all made perfect sense. I watched the Apollo 11 and Apollo 13 as they happened, and still have audio tapes of the radio communications. People do seem to be getting dumber.
Being in freefall and being weightless are the same effect. It's that old Einstein thought experiment of a man falling from the tallest building on Earth and a man floating freely in the farthest reaches of space experience the same amount of gravity.
I’m so jealous you got to see that. I’ll agree that my generation (millennial) aren’t always the greatest and there are a few to msny conspiracy nutjobs
You should post the audio to CZcams. That would be very cool.
I'm in agreement about the audiotapes! Get those babies digitized and posted on youtube! :D
I think it's less people getting dumber, and more people having been surrounded by accurate information back then. In the 1960s, you couldn't walk two steps without encountering an expert talking about the moon landings. Now, you need to actively search for one. Also, the information was being reported live in easy to read chronological order. Now, when you look it up, you need to order and structure the information yourself.
I wish more people played Kerbal Space Program.
Even as an engineer, I learned so much about rocketry and orbital dynamics from that while having tons of fun.
fr, since i was a kid i always understood the concept of an orbit (object b revolves around object a) but i didnt really understand what it was and how it worked until i played ksp
I’ve been building some really impressive stuff in KSP lately and it’s making me want to go back to college, change career paths, and go into aerospace engineering
@@ryanjones4106 same, to be honest. I originally wanted to study aerospace engineering, but ended up going into electrical engineering in college to have a wider range of career options.
Watching all the current space companies lately is making me want to get that AE degree and apply at SpaceX.
Yes indeed I wish I knew about KSP when it was first released, only discovered it about 2 years ago. It's great and not easy at all, really forces you to learn what you are doing to get anywhere. Waiting for the sequel to mature more in early access.
KSP with the N-body physics mod really makes you appreciate the difficulty of IRL spaceflight
Everything I know about rocket science, I learned from a little green Kerbel. :D
❤
I understand the lunar landing because I’ve failed hundreds of Mun landings
Mün or bust!
@@yesserucame here to say this exact phrase haha
@@ryanespinoza7297 LOL tell me about it. I don't think i ever stuck the landing either, i did manage orbit and return though.
Great explanation. A small correction: 5:53 The moon's mass is 1/81 that of Earth and so its gravitational pull is 1/81 that of Earth (not 1/6) when measured at equal distances from the centres of both bodies. The moon's SURFACE gravity is 1/6 that of Earth - the difference being because the moon is smaller and so its surface is closer to its centre.
And the red and blue arrows representing the gravitational forces wouldn’t be equal halfway between the two bodies but that’s just nitpicking.
You’re wrong.
Gravity of the Moon relative to the Earth = (radius of the Earth / radius of the Moon)^2 × mass of the Moon / mass of the Earth
(6371/1737)^2×(7,3×10^22)/(5,97×10^24)=0,164=1/6
@@Godzilla_28 You just made his point again, it's 1/6th at the SURFACE of the moon. In your formula you use the radii of both objects. But his point was the overall strength of the moons gravity is 1/81 the strength of the earths. Sure they would be fighting 1/6th the gravity of earth when taking off from the moon, but this would drastically drop off as they maintain a steady climb.
Just wanted to say thanks for doing the math! Neither of you are wrong, but explaining the same point.
@@thearchivalist6749 Yes, that's right. I misunderstood, so let's get this straight. When comparing the relative strength of gravitational fields, the Moon only reaches a significant gravitational force at a distance of 1/81 the distance that the Earth's gravity reaches. But if we focus on the relative strength of gravity, the Moon has about 1/6 the strength of gravity compared to the Earth, especially at the surface.
@@Godzilla_28 Only at the surface, due to r.
I liked the graphic that showed the hill from the earth to the moon. That's really useful.
The thing that I am always most impressed with is not the fact that they could get there and back, but when they came back, they could pick a spot to land and hit it within a couple of miles, at worst. That takes some real calculating.
Yeah and they did the calculations with slide rules and pen and paper.
@@isaacbruner65what’s so surprising about slide rules, log books and paper? People got by without calculators for a long time. Even when I was at school we got books with log tables, constants and the like and weren’t allowed calculators for some exams.
Even at university we were usually given examples and tutorial questions that could be answered without a calculator although even trying to follow some mathematicians writing on the board I usually ended up with a page or two of extra steps because I couldn’t keep up in my head all the time.
The preliminary calculations were done by computers on the ground: BIG ones. As the spacecraft were tracked, the computers on the ground calculated updates and sent them up to the astronauts. The onboard computers were only used to convert the final delta-v numbers to engine burns. And incidentally, both the orbital insertion burn and the trans-earth injection burn had to be done when the astronauts were out of communication with earth!
@@allanrichardson1468 The slide rules were used for quick checks and small corrections ...
The Gemini & Apollo capsules did not just fall out of the sky (I'm not sure about the Mercury capsules). By a clever bit of engineering, they were designed with the centre of gravity offset from the aerodynamic centre, which meant that it would naturally fall at an angle to its ballistic path; which causes lift in one direction. By rotating the capsule about the centre of gravity the direction of the lift was changed giving a limited ability to change the flight path either side to side or long or short.
This also meant that from the point of view of the crew, not only did you have the high Gs’ of atmospheric deceleration forcing back into your seat (& your nappies) but at times you might be flying on your side, or even upside down!
As a KSP player, I approve of this explanation
A KSP player probably tried this and didn’t have enough fuel to make it there
multiple times... till it worked...😂
Jeb finds a way
Late to the party, but yeah, watching this just makes me way too fire up KSP again 👍
What did people think was in that 363 foot tall rocket? Do they not realize when you throw a ball straight up it starts slowing down as soon as it leaves your hand?
Yea, they got the rocket to 24000 MPH using the upper stage of the Saturn 5. The Saturn 5 rocket was a Saturn IV-B rocket sitting on top of yet another rocket.
The vast majority of the fuel needed to reach the moon is used up in just getting into low Earth orbit. You still need quite a bit of fuel for the TLI, but it's still just a fraction of the fuel used to get into orbit.
You slow down most of the way to the moon, then you only need to slow down a little bit to enter a lunar orbit.
To return from the lunar surface you only need a small fraction of the fuel needed to reach Earth Orbit, then to leave lunar orbit you slow down to return to Earth.
Are you familiar with the Artemis project Artemis needs to refuel in low earth orbit? Is estimated 15 starships needed to launch up fuel so the can get to the moon. Modern rocketry is saying they need to refuel to get there. They're using a different fuel.
Seems odd. If they have they play book why are they not using it.
I don't know if we went to the moon. But I don't think we're going back anytime soon.
@brizzlefarmizzle no, artemis dosnt need to refule, starship does but not the SLS. All this takes is a quick Google search.
By getting into orbit, you are half way to anywhere.
@@brizzlefarmizzlethat's because starship is a flawed concept and is horribly inefficient. We really should have picked another company for the lander.
@@AHHHHHHHH21 15 launches is a bit much to go correct each time and logistically a nightmare
Knowledge is power! And my old man working at NASA from 62-73 helped as well.
They think spaceflight is like cars where you have to constantly run the engine to keep moving.
That good old apollo V8 ..... 🎅
Exactly what Vlad seemed to think on MCToon's livestream the other night.
That's one of the points/misconceptions Bart Sibrel loves to spew in his gish gallop.
Thanks Dave. This is the best description of orbital mechanics I've ever seen. Scott Manley would be impressed.
The deniers deny bc they can't fathom the engineering and teamwork required to make that happen.
hell, they can't even walk and chew gum at the same time
@@victorfinberg8595 not sure alot of these people can actually walk
~5:00 another inaccuracy: the Apollo missions followed a free-return trajectory. That means that they in fact _did_ shoot for apoapsis higher than the moon, because they weren't aiming for the optimal elliptical trajectory, but for a "figure 8" trajectory that would result in a retrograde orbit around the moon (i.e. in opposite direction to the initial Earth orbit) and if the spacecraft's engine failed when approaching the lunar periapsis, the spacecraft would get a retrograde gravity assist off of the Moon, sending it back towards Earth without using any more fuel. Lunar flyby missions that return to Earth using this trajectory don't need _any_ burns beyond the initial translunar injection burn.
If they used the optimal elliptical trajectory, in event of an engine failure the gravity assist off of the moon would yeet the spacecraft out into solar orbit.
Solar orbit?
Well done. Perhaps the most cogent and direct treatment of orbital mechanics I have seen.
As someone who can grasp the underlying principles but is useless when it comes to math, this was very informative.
Dave, this is just brilliant mate, you have actually just about converted my nephew(a long time moon landing denier!!) I thought he was a lost cause but your ability to communicate has made him see the light. Thanks for the content keep it coming please👍🏼👍🏼👊🏼
That's amazing to hear 😊
Silly boy, he was right all along.
Is he still in school? Then maybe some hope. An adult watching this and needing to be convinced is 100% a lost cause no matter if they change their mind after, it's still a brain that went really really really bad before.
Wow. Someone tells a story and you all believe it because Dave said so ?
You all obviously haven't heard that the most advanced American, unbiased neural AI, which you can call misinformation at your own peril, at the AI world conference 3 weeks ago, called your Apollo photos FAKE.
The photos of the Chinese rover photos sitting side by side with yours, were called by the same AI, genuine.
Your nephew was absolutely correct.
Before you come back with the usual abuse, go and check yourself. It's hard to find in your country though, wonder why.
So your options are to admit he was right and you weren't, or argue with AI. Your call. As it improves, that itself will become very challenging.
One moon nut said that AI only copies what it sees on the net, exactly, all I see is videos about this great lie being true so that's not a point.
The evidence has been there forc50 years of you'd have just used logical thinking instead of emotionally charged patriotism.
Good luck. Enjoy your awakening.
@Seigensi you need schooling right now mate, read the above comment, your Apollo is fake.
Social media, politicians, and the main stream media has so polarized people that even when provided with simple, well thought out descriptions and information... just won't change their minds. They're so willing to listen to trolls or poorly educated individuals that happen to excel at word-smithing or manipulation of information.
However, thank you for your efforts. Very well done.
It's also the decline in education in the last 40 odds years.
This is brilliant. Well done, and thank you for taking the time to produce this!
Dave, thank you so much for your explainers. I so appreciate that (as far as I have ever seen) you do not insult or attack the people who have embraced un-scientific, outdated ideas about the shape of the earth and the nature of space.
I know that mocking flat-earthers is low-hanging fruit and their tendency to spew vitriol makes it tempting, but I really think your videos are doing more good than a video mocking them ever could.
Would be more fun though, below average humans (and other animals) can make themselves feel better by seeing they aren't that stupid and science deniers aren't unaware of how wrong they are, they just like being the center of attention and by annoying people who are 10x smarter than them they get to feel influential and important when they aren't.
I really appreciate the quality of your videos. Many other debunking channels focus too much on mocking wrong beliefs, rather than educating why those beliefs are wrong.
I hope you continue making videos for a long time.
You at least have that right. These so called de- bunkers first start off by saying that we that know they never landed say thing we don't. They have to as they can't argue with the fact that we have already with science facts de-bunked and shown they could never have been on the moon. Now what he has said in this video is what anyone with half a brain Already knows. Mind you there are some idiots that when firing at a moving target just don't know you have to aim in front of it. Lol
This is by far the best explanation of how moon landings are done that I've ever seen.
Having studied orbital dynamics on the way to an an aerospace engineering degree I can understand people’s confusion. Transfer orbits and delta V calculations are not easy to wrap one’s head around.
I also studied some orbital dynamics en route to an aerospace degree and totally agree that it’s a confusing topic for most people.
However, the bare bones basics that people should understand aren’t too bad. You really only need to know that you do math to figure out trajectories and do short burns. Then you mostly coast and let gravity do most of the rest of the work.
The difference between the average person and a conspiracy theorist is that the average person accepts that they don’t fully understand orbital dynamics and trust that experts do. Meanwhile, conspiracy theorists go full Dunning Kruger and using only their ignorance declare it’s not possible.
@@AM-rd9pu it did take the fun out of most sci fi movies. Always have to turn the brain off when they show anything to do with orbital maneuvers. Lol
Speed up to slow down :)
@@chrissmith7669Not to mention “asteroid fields”
@@oberonpanopticon I was just getting confident with hohmann transfers in circular coplanar orbits when they threw eccentricity and non planner orbits into the mix. Mind blown. Lol
Personally, I didn't need any explanation, I think I understand orbital mechanics well enough, but your explanation and graphics were spot on and should convince any open-minded person that going to the moon was not impossible, just difficult and expensive.
Dave, you are a fantastic educator. The way you can convey complex astrodynamics that NASA had to figure out into simple terms is nothing short of fantastic! You really make me pay attention as you speak!
What the hell do the flerfs think was in the Saturn V's fuel tanks? Hopes and dreams?
Unicorn farts and moonbeams.
It was obviously a giant helium balloon
at least some think those fuel tanks are fake and are actually just helium filled balloons lol
Thoughts and prayers
compressed air did you not know that?
So basically the cannonball is falling to Earth, but its speed is so fast that that speed is actually preventing the cannonball to fall to Earth. That is what an orbit is.
Very informative from start to finish, explained thoroughly while not letting it drag on.
I could watch a lot more of these, very nice.
The car analogy makes so much sense and yet and I never once thought about it. You truly are a master of explaining concepts. Bravo Dave!
The elliptical orbit called a Hohmann transfer orbit, used to transfer a spacecraft between two different circular orbits around a central body in the same plane. It is the most economical path in terms of fuel and energy, but not the shortest or fastest. It involves two impulses, one to change the spacecraft’s speed and direction at the first orbit, and another to circularize the orbit at the destination.
The manoeuvre was named after Walter Hohmann, the German scientist who published a description of it in his 1925 book, ‘The Attainability of Celestial Bodies.’
Using the Earth's atmosphere to break offered even more efficiency. The return capsule could shift it's angle to "steer" through the atmosphere in a complicated wave-like maneuver that allowed it to aerobreak without burning up. The nerds that designed this rocket were truly amazing.
I don't have an issue with someone saying "I don't understand how they could do it, so I'm skeptical...", or "I don't know, so I'm not sure if we did or didn't, what's the evidence?" as I learn more about the Lunar Missions all the time. And, you have to admit, even the experts at the time were doing things beyond their knowledge and were learning 'on the go'. That's what made this So amazing and impressive.
But, those who say "This is Fake!", because they don't understand, or can't fathom what it took, that's Not OK. That's a Positive Assertion from Ignorance. "I don't believe" isn't evidence.
Great video, those who are in the "I don't know" and "I don't understand" camp will Love videos like this. And people who are genuinely interested still learn something new from time to time as well...
The manned lunar missions were really dangerous. That's probably also a reason why they don't do it any longer.
@@d_vibe-swe The reason was way more of "Ok you went to the Moon, we said that we won to the soviets and now nobody cares. And look at all the money that could be spent way better, like on a war for example."
What makes it even worse is the information at their fingertips. They could learn about it so they could understand it. There are plenty of videos just like Dave's that explain it in different ways to help people understand. Or, if they want a more hands on approach, there are games that allow you to play "rocket scientist" and try to achieve similar things. Kerbal Space Program is a good one for that, but even 30 years ago there were games like "Lunar Lander" that at least had the basic physics down.
@@d_vibe-swe True, Very dangerous. But, come Artemis 3, people are going back...
:I don't have an issue with someone saying "I don't understand how they could do it, so I'm skeptical...",:
I do. If that someone doesn't know anything about physics, and then claims to be skeptical because of their ignorance, then, yeah, that's a problem.
"I don't understand how they could do it. Maybe I should learn" is a much better response.
Thanks so much for these clear videos I have always been a moon landing buff (I am Canadian and was with my parents visiting relatives in Zurich at 7 years old when we all gathered in the livingroom to watch Armstrong take his historic step) and your videos have simply explained so many details of the flights I never knew or thought of. And, as a somewhat of a professional photographer I absolutely love your videos about lunar photography. Keep up the good work!
I was just trying to explain the Apollo mission to my eight-year-old grandson, and he asked about the fuel and my answer was so lame compared to this simple and correct explanation. My favorite is the analogy of the incline and coasting to the moon in a car
Moon landing deniers should get a discount on KSP😂. Also this is a really good explanation of orbital mechanics. It makes something extremely complex seem almost intuitive.
I love these spaceflight videos! It's my number one favourite topic, and I love hearing your explanations to some folks' misconceptions, even if I personally know most answers (not all though! Hearing the exact numbers for Apollo's speeds and altitudes is really nice!)
Greetings from Argentina!
I agree, and thanks for your perfect punctuation, a welcome relief.
@@kernicterus1233 Heh, well we're in a proper video aren't we? Thanks for noticing.
14:55 There's a reason people talk about "gravity wells" of planets and stars 😉
Great video! I'd just add that if only it was possible, it would be preferable to have a much lower speed when coming back to Earth - less danger of burning up in the atmosphere! But having lower speed would actually require _more fuel,_ because you'd have to use it to decelerate along the way. Just being dropped with no initial speed from an altitude of the lunar orbit is what accelerates objects to such ludicrous speeds - for anything less than that, you have to burn fuel.
the air is basically free fuel!
I agree that it would be preferable to enter the Earth's atmosphere at a lower speed and as you say, that would be difficult to do. Minor nit pick: The point where you could return to Earth starting with no initial speed relative to the earth is not Lunar orbit but is the point just on the Earth side of where Earth and Lunar gravity are the same magnitude. This is much further away from the surface of the moon than the height of Apollo Lunar orbits. An additional engineering problem would come about because doing so would greatly extend the time of the return trip because the initial portion of the trip would be at a very low velocity. This means a lot more crew support time would be required and that mean more mass for oxygen, food, etc...
WELCOME, to SPACETIME!
Before I even properly get into the video, KSP taught me so much about the mechanics at work here. What a great and valuable tool for space education
That was a very clear video and really helped me understand all the nuances of the flight. Thanks.
I have a degree in physics (University of Wales, BSc. Hons) and I thought that was as clear, succinct and comprehensive as possible! Excellent presentation Mr. McKeegan. Thank you. Sadly idiot or brainwashed flerfers will just hand wave it away without any attempt to understand.
I was waiting for him to break out the differential equations and solve them for the amount of fuel needed. 😉🚀
Did you expect flerfs to understand this?
Maybe not, but education is the best way to prevent new flat earthers.
No way, this is for people of average intelligence +
Great video as always, Dave. How you have the patience to answer the nitwits is beyond me.
Another intersting point to consider, when you look at th hard numbers, the Ascent portion of the LM had a MUCH higher thrust/weight ratio on the surface of the moon at 2.08 than the SaturnV stack had on the launch pad in florida at 1.23. The fuel accounted for 50% of the launch weight in the ascent stage, which is less than the 75% of the full stack on earth. And the. The emgine of the Ascent stage has a higher specific impulse (specific impulse is basically the miles per gallon/ km per liter for rockets.) than the F1 engines of the saturn V. Its 1.18 times more efficient. Now consider that the LM didnt have to fly to as high an altitude as the launch from earth, and the fact that it wasnt fight air resistance for the first keg of its trip, and the math makes it very evident that it was a walk in the park for the LM.
Math doesnt care about personal incredulity
There was a reason for that. If an abort occurred near the lunar surface the ascent engine needed to quickly arrest the downward motion of the ascent stage and get it going upward again as fast as possible. Hence the need for the high thrust to weight ratio. Buzz Aldrin commented on upward acceleration during the lunar liftoff by saying, "We went out of there like a scalded dog."
@@joevignolor4u949
Nice. Hadn't quite heard that before lol.
Kerbal Space Program. If you can't wrap your head around rockets, gravity and how they interact with one another - play this game. It's fun and educational. Beware however; a majority of the celestial bodies encountered here are of the spherical variety ...fantastical as that gimmick may seem.
Great video.
Sadly, the people who can't figure out that the Earth is basically spherical or that gravity isn't a hoax probably aren't going to understand or believe a word of it. Therefore, they'll just label you a lying NASA shill and move on with their idiocy.
But, you did great work here!
They only 'think' gravity is a hoax because it is next to impossible to deny the earth is spherical without also also denying gravity.
The amount of engineering that went into the moon landings is absolutely incredible. The more I learn the more impressed I become. The fact that people will deny the hard work and accomplishments of the hundreds, if not thousands, of scientists, mechanics, etc., because they believe in a nonsensical conspiracy borne decades after the events is deeply sad.
Yes. There’s a CZcams site called “One Big Monkey Apollo Stuff” that I highly recommend. He’s compiled so much great information there that’s very in depth. Pretty amazing effort that really does justice to those incredible times.
It seems to be a common issue that while most scientists and engineers have no problem admitting that they know absolutely b*gger all about art and humanities,and will not pass judgement on it, arty types, however well educated, seem to have trouble admitting (or even realizing) that their inability to understand the engineering it doesn't make it fake.
@@thearmouredpenguin7148 I suspect that most arty types, like myself for instance, firmly believe that those who excel in the STEM subjects and then go on to be part of NASA and other Space Agencies around the world are gifts to humanity. Without those kinds of people, I'd be scratching my rough drawings onto cave roofs with a rock otherwise.
Hundreds of thousands. Roughly 500,000 people worked on various parts of the Apollo program. The vast majority outside contractors who never had any contact with NASA. But people think all of those folks were somehow in on it.
As a Kerbal space program player im just giggling about that thought and how they think they just point at the moon and go straight
With enough boosters you can do anything
thank you Dave for explaining this to us. all the little details that have to be considered for a successful spaceflight.
i hope you reach you 100k Subscribers soon - preferably in time for Christmas, or at lest until New Years Eve. that would be nice.
You are simply amazing. I didn't know all of these details and you explained it in such simple terms that made it tangible for a layman like myself. I wish you were a teacher! Haha
Thank you, so glad it has helped
You debunk so clearly and precisely that it's a pleasure to watch your videos, Dave! Thank you for all you do. ❤❤
Best explanation I have heard since, since, wait for it, The actual LIVE coverage taking place DURING the trips to the moon. It was all laid out with full explanations and demonstrations at the time.
I mostly came to this channel for flerf debunking which is super fun and I hadn't heard of these questions about the fuel and speeds of the Apollo before and when they were presented I thought: huh, how DID they do that? And your explanation was excellent and made me learn about stuff that I hadn't even heard or thought about before, love your content
Agree with this. I'm sure a lot of the comments which Dave gets are from flerfs and deniers, but there are probably a load of people who just, like you, hadn't really thought about it and seriously wondered why Apollo didn't need huge fuel tanks all the way to the moon.
Here's waiting for a Scott Manley collab.
Oh Hell Yes!!
Excellent work, clear and concise, as always! Thank you!
Man, you really did a fantastic job explaining this topic. Well done!
very nicely done. well-constructed explanation and graphics, simple, clear. easy to understand.
Thanks Dave. That's the clearest explanation I've seen so far.
I've come to the point where when naysayers say, "It's just common sense," I take it to mean, "I'm too dumb to understand complex multidisciplinary topics, therefore it didn't happen!"
Can you explain why Artemis needs to refuel in low earth orbit. Dumb question. Why are they using a different fuel? All this math makes sense here but he's not accounting for the gravity of sun pulling you away from earth
@@brizzlefarmizzle It doesn't. The test flight from the SLS/Artemis mission performed half an orbit until they were in position, then performed their trans-lunar injection burn and went straight to the moon. No fuel stops. You're thinking of SpaceX's Lunar Starship, which will need to launch the upper stage with minimal fuel just to get it up to orbit because Elon Musk needed to have a bigger -dick- rocket than everyone else to massage his insecure ego.
I never doubted the mission but thank you for your excellent job of helping me better understand how it all worked. Very clever!
Very well explained as always 👍Amazing what you can do with some actual research 😉
He does his own research?! (Enter Flerf audio compilation ).
And Dave's segway to his sponsors are epic!😂
@michaelschaedel1442 for your information, and with hope that it's received well, "Segway" is the incorrect spelling. It's actually spelled "segue".
Perhaps the best video on this subject I've seen. Perfectly clear from start to finish, including the parameters one at the time for better understanding, and using simple but pertinent diagrams and analogies. Extremely good popularization, thanks a lot.
Brilliant video. Nicely explained. I knew this stuff already but still found your video to be really interesting. Well done .
Very nicely done, Dave. And congrats on 100,000 subscribers.
The command module main engine was an AJ-10, one of the oldest rocket engines made by the US. First used on Vanguard, variants of the engine have been used by Delta, Apollo, the Space Shuttles, and the Orion capsule.
A variant of the AJ-10, which used a Different Fuel than the Vanguard Variant, and almost 3 times the Thrust
I have for the first time been truly educated about the science and engineering involved in the Apollo program. Thank you
I was 5 when they first walked on the moon, and my memories are a bit muddled about what I actually understood when - but as a child throughout the Apollo program, I did understand and was fascinated with the whole idea that they were using small amounts of fuel to maneuver into long elliptical paths around the earth, paths that would ultimately intersect with exactly the right point near the moon to us small amounts of fuel to change the path so it was just going around the moon, then doing the same stuff in reverse to get back to Earth. I in no way understood the math - still don't, actually - but the basic idea is simple enough a child can understand it.
This was one of the most interesting and informative visual diagrams of how orbital and rocket mechanics work. I mean, I general understood it, but this just solidified a few things for me. Thanks, Dave!
Thanks for yet another informative and entertaining video.
Fantastic explanation in a very simple to understand format.
I’ve listened to this several times now - such an enjoyable and informative listen. Thank you Dave.
Playing Kerbal Space Program also really helps to understand these concepts :)
Great explanations, nice graphics. Thanks Dave, this is a good one!
For those who want to have a great understanding of spaceflight theres a game called Kerbal Space Progam, if you manage to learn the game hard enough to get to the moon, you will unestand much of the concepts of this video in practice
Finally someone explains it for me so I can understand, great job keep it up
Good one Dave ! I can hear the nuh uhs from here.
The other interesting thing about rocket science is that the more fuel you use, the lighter your craft (+fuel) is, and so the easier it is to gain more speed (and the easier it is to slow down).
I like to use the analogy of having a backpack full of beer when going on a hike. And the more beer you drink, the lighter your pack becomes; and when you're more drunkered you don't care as much about the weight anymore. Maybe not the best analogy, but I do love beer, and I do love analogies, so mixing the two is great.
that is an analogy if I have ever seen one.
@@troybaxter Haha, thanks, I do love a good analogy!
This is why a rocket needs the most thrust right at liftoff. It's almost fully fueled so it needs all that thrust just to lift it off the ground. As it goes up and the propellants are expended the rate of acceleration gradually increases. This is why the astronauts riding the Saturn V went from 1 G at liftoff to about 3 G's when the 1st stage burned out, and that was with the center engine being cut off about 45 seconds earlier than the other four to reduce the rate of acceleration.
My favorite is the old “how do the engines combust if there isn’t oxygen?”. Flerfs always expose themselves doing zero actual research.
I adore when these idiots try and say anything about space travel, since it's one of my favourite areas to research. You hear two words out their mouths and realize they know nothing and have no interest in it
@@Tom--pf8ubRight? A child with a barest hint of interest and curiosity has a literal dearth of information at their fingertips.
Flerfers have a lot of questions, but are uncurious and not interested in learning how and why things actually work.
@@SeanCrosser They just want to be right, desperately, because they're not smart enough to be right about anything else. It's sad, and I hope they can snap out of it someday. At least the truly conned ones; the conmen and grifters can well and truly go fuck themselves.
Let me clarify, actually; they are ALL smart, since they're human, but the problem lies in believing the wrong things and being afraid of changing beliefs, being afraid of being wrong even if learning from mistakes is a very intelligent and admirable thing to do.
Don't forget the ever-popular "rockets can't work in a vacuum".
Great video. A complicated subject made easy to understand.
You could’ve literally never explained this better for people I love that you left no questions or room for theories
"If you cannot explain a complex topic in simple terms, it is because you don't understand it well enough." - attributed to Richard Feynman
Such a great video....brilliantly explained!
This was discussed yesterday on McToon's stream.
Except it's a bit too obvious that Rad Vlad is only in it for the attention. You can fix stupid, but not willful ignorance.
I haven't had a chance to catch up on that stream yet
The explanation as illustrations are well done and easy to understand such a complicated topic such as orbital mechanics. Nice job 👍🏾
I guess deniers think that if they can't understand how something works, no one else can either. How do they rationalise their own iPhones? Not many people truly understand exactly how all of those incredibly complex devices work.
The Matrix. Yep, the Matrix..