How Apollo Astronauts Didn’t Get Lost Going to the Moon

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Special thanks to wehackthemoon.... for helping make this episode possible. Be sure to check out wehackthemoon.... for more behind-the-scenes looks and unsung heroes of the Apollo program.
This video kinda broke my brain... if you're still a little confused or if you're like me and retain things better when you read about it, check out my companion blog post over on Discover.
And more even older space in my book, BREAKING THE CHAINS OF GRAVITY! You can order your copy on Amazon: bit.ly/astbtcog
My blog archives has lots of awesome olde timey space, too (and I'm looking for a new home for it, too!): www.popsci.com/...
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[@FandersonUfo]

Always nice to have something new Amy. Understand you're busy. We'll take what we can get out here. Thanks for another great video.

[@danaterlecky787]

My father was an electronic draftsman. He died in prematurely in '63 while working on what I think was part or the IMU for the LEM. The company he worked for was a sub contract in that kind of thing. I was only 11 at the time and his death was contributed to long time in the pacific in ww2 so i only gather what he told me then. He also told me that they worked on the XB70. Thanks of the post

[@jillkon6763]

sorry for your loss......i am sure your dad did some neat stuff !

[@davidkanera7445]

So glad you're back. You always pick the most interesting, oh I never thought about THAT topics. And you have such depth of background and you dumb it down so well!

[@davidkanera7445]

@M Detlef I wasn't even born yet.

[@TheVillainOfTheYear]

Most of the Apollo astronauts studied that star navigation at the Morehead Planetarium in Chapel Hill, North Carolina, on the UNC campus. That’s definitely a special place.

[@anthonycook6213]

Specific training for Apollo missions was conducted mostly at Griffith Observatory in Loa Angeles, from September 1966 to mid 1970.

[@jeffvader811]

When Issac Newton came up with his cannonball thought experiment 400 years ago, he probably had no idea that one day that idea would be used to send people to the moon. Incredible.

[@sharplessguy]

Thanks Amy... this is the second time I watched this. It's good to see you posting more vintage space content.

[@Heart2HeartBooks]

This is no different than how I Navigate from my local pub to my home on an early Saturday morn.

[@2AForever-wi8yj]

Guess I'm lucky my car knows the way

[@alexwright6038]

you cover twice the distance?

[@lizardbyte]

Are you suggesting Neil Armstrong flew drunk? How dare you sir! Oh I knew Neil and he never drink past the van Ryan belt!

[@whyyeseyec]

However, the contents contained within the pub can have a detrimental effect on your return trajectory depending on the amount of said contents consumed and their affect on the users internal guidance platform.

[@Swervin309]

I always enjoy your content. Very informative and made simple to understand. They way your eyes light up, when narrating, is indicative of your passion of the material.

[@franksafranek7405]

I like the new graphics. Awesome presentation as always.

[@rogerdalesk]

All of Nasa's photos or images taken in the last 50 years are computer graphics they have been manipulated by Nasa to hide whats is really on the moon and Mars!

[@globalmagicnation8464]

RayDT No he’s pretty much correct. Simple Google search will prove that to you. If you still believe NASA is not full of BS in 2019, what won’t you believe? Just go look at Nas his own website, it’s all CGI. Do you actually believe NASA lost the telemetry data and that’s why we cannot go back to the moon? Let me guess you’re still waiting on the commercial flights into space that get promised every five years?

[@kinsmansteve]

@@drtidrow Rubbish, indeed!

[@globalmagicnation8464]

RayDT Traveling in space is only a figment of your imagination. You are the fool not me. Plenty of evidence proving we didn’t go. You will never see Low earth orbit, you will never go beyond low earth orbit in your lifetime. All you will ever do is sit here and imagine it in your head and look at CGI photos and think it’s amazing. You will not even question why we haven’t been there in 50 years. You won’t question why NASA says we lost the telemetry data and can’t go back. Yet you’ll call me foolish for not believing we went 50 years ago in a lunar craft made out of foil. You probably believe you came from a monkey as well. Whatever, I will let you get back to your regular scheduled program.

[@johnwynd5561]

GlobalMagicNation - I love reading the paranoid rants of you space travel deniers. The good news for you is that God watches out for drunks and fools.

[@patrickmowry1650]

Thanks for having time to post again, you and Scott Manley keep me educated and entertained.

[@whistletutor]

Great content - been a subscriber for a while but I don't think I've ever taken the time to say how much I love these vids! Cheers from an 8-time Space Camp grad (not bragging or anything... :)

[@mccloysong]

Your research is always impressive.

[@paulwells5364]

50 years today since the eagle landed on the moon. So awesome.

[@lizardbyte]

The moving hills and valleys of space! Oh the perfection of it all!!!!

[@richardstedronsky5170]

Any chance you could do a bit about the Agena Target Vehicle? I'm a big fan of the Gemini program and always wanted to learn more about the Agena vehicle, the issues it had, etc. Thx!

[@rocket60saturn7]

Outstanding summary of the navigational logistics. I knew 4 of the astronauts that landed on the Moon. Your analysis is spot on. It just so disappoints me that some of the present generation thinks we never went there. Believe it or not, your grand parents were pretty damned smart. That is why you have the tech you have today. We paved the way.

[@varuzhshakbazyan5732]

They were great liers, filmmakers, photographers, propagandists and thieves. A bunch of Nazi's that ran NASA would never lie to the American public oh no. They swindled 40 billion dollars of tax payers money and for what? What do we have to show for it besides their movies and photos.

[@joevignolor4u949]

@@varuzhshakbazyan5732 Here you are again making more claims without any hard evidence to back them up.

[@varuzhshakbazyan5732]

@@joevignolor4u949 Apollo 17 magazine 134/B. Photos AS17-134-20383, 20384 and 20385. It's right there on flicker. The flag clearly has moisture on it, those photos were not taken in a vacuum. Water cannot exist on the moon in any form besides ice. Also, the flag is nothing special, it's not made of aluminum or Mylar or titanium. It's just a plain old cloth flag just like the one hanging everywhere in America. I would love to hear any explanation for how there can be moisture on the flag on the moon. If they faked those photos then the question is why? All they had to take a baseball up there and throw it. Or have one of them jump straight up like 6 feet off the ground. Did they do that ? No. Because they were always on the Earth.

[@whyyeseyec]

@@varuzhshakbazyan5732 - Did those great liers, filmmakers, photographers, propagandists and thieves also purposely kill 7 astronauts each during the Challenger explosion in 1986 and the reentry of Columbia in 2003? Was that for our personal enjoyment?

[@Par-Crom]

The content of this video is so good even the bots don't dislike it.

[@TomwithaDream]

So glad you're back! I enjoy your content quite a bit. Short and informative and just in depth enough without requiring me to get pen and paper to follow along.

[@Petertronic]

I'd love to see you build the new Lego lunar lander. Your Saturn V build was such fun :)

[@AmyShiraTeitel]

I just got it in the mail! The build will probably happen the week after next.

[@Petertronic]

Yay!! I have started building it, and it's awesome. Good luck! 🐱🚀

[@DRUmBEaTTS]

Yay I was going to ask that too! Can’t wait to watch you build it! 🙂

[@JM-lc3ki]

The Vintage Space I love the subtle KSP theme in the background lol

[@charliesmorykin38]

Listening to your station and how things worked is awesome just want to say thank you for doing what you are doing

[@TheJimtanker]

Love the KSP ambiance in the background.

[@vancegodin4149]

Just commenting to keep creating blips on your telemetry... u r awesome!

[@TheStuport]

Love your researched and thoughtful topics especially as next month as we all know is The 50th Anniversary of the First Moon Landing WITH astronauts! Your delivery of facts and information allow even a knucklehead like myself to absorb what I'm viewing and hearing. You absolutely Deliver The Goods and we here on Earth are The Lucky Ones.....Cheers From Ohio known as Neil Armstrong Country

[@firewaterforgeofarizona4304]

I love your videos. As far as I know, there's no one else on KZbin doing this. As someone who's always had questions about the Apollo program, I really appreciate your videos.

[@robbabcock_]

The watercolor-looking graphics are sweet! Great video, Amy!

[@DagarCoH]

I agree. Where are they from and can one access these?

[@icychill105]

cool to learn more after having seen the apollo exhibit at the museum of flight in seattle, WA. amazed at the size of the capsule and engines from the saturn V rocket

[@murph914]

My dad worked for Draper in Cambridge. Thanks for filling in all the missing pieces i have been wondering about all these years Amy.

[@davidcaddell3770]

Thank you Miss Amy. I have thought about this from time to time, but never seriously. This was very helpful. Sure was interesting.

[@philmiller681]

Interesting. I was reading day 2 of the Apollo 11 journal online today. Much of it was about Michael Collins taking sextant readings on stars.

[@joshuaallen4181]

To use a different sports analogy, I have always thought of traveling to the moon as being like a quarterback throwing to a receiver on a deep route. The quarterback does not throw to where the receiver is but to a point where the receiver will be at the moment when the ball gets there.

[@nathanwahl9224]

Good analogy. All while navigating through variable defensive player positions (gravity anomalies.)

[@epiendless1128]

"The engineers and scientists who built the onboard navigation system brought centuries of studying the sky to bear on the problem." Exactly. Our forebears weren't stupid. And neither were _their_ forebears on who's shoulders they stood. Even during WWII we had mechanical computers that could fire a shell from a moving ship and hit a target over the horizon, or fire a shell at where a bomber _would_ be once the shell reached that altitude. It's impressive, but at the same time entirely comprehensible.

[@malcolmbacchus421]

Epi Endless Electro-mechanical fire support tables were around in World War 1 pioneered by the Royal Navy.

[@mikimisko6753]

over horizont,.you mean over curve of the earth, really?

[@raviscott4853]

There is even OHR that can detect F117 and B2 stealth aircraft

[@scottmerritt9877]

Malcolm Bacchus Yes indeed. They deserve a lot of credit for “continuous aim” and for sharing it with the U.S.

[@MrJackHackney]

I’m typing this from my portable Navigation system. It’s got a gyroscope, accelerometer, GPS, guidance computer and more. I was able to Navigate to your video using it! I believe the Apollo project was a catalyst for speeding up the development of what I have in my hand!

[@varuzhshakbazyan5732]

Nonsense

[@Trapster99]

Outstanding! You took a very complex issue and made it understandable, and told the story completely. Well done!

[@pwolfman1227]

Go watch Hidden Figures. Lol. Couldnt have done it without Colored Folk. Lol.

[@dukecraig2402]

@@pwolfman1227 Hidden Figures was a bunch of malarkey, it's true Katherine Johnson and those other ladies were indispensable but the whole thing about them suffering racism at the hands of NASA employees is pure bunk, read anything written by Johnson herself and you'll see that she was made to feel very much at home and appreciated by her coworkers at NASA and that she considered them family, but the racist movie maker couldn't resist but to lie because as with all liberals and their mentality "If that's not what happened it should be", just like "Hands up don't shoot", when it turned out that's not what happened that day the liberal media kept reporting it that way because of course "If that's not what happened it should be", I didn't get to see it in the theater but being a life long fan of the space program because I had an uncle who worked at the Cape I bought the movie as soon as it was in Walmart, after watching it at home and seeing how the NASA personnel were portrayed I immediately threw it away.

[@jasonvivada911]

I love your videos. From a fellow space enthusiast Always wanted to be an astronaut so I really Enjoy your videos it has a lot have a lot of great information keep up the great work

[@ToTo-ox8mg]

Dear Vintage Space, thanks again for an awesome video! May I ask will there be a special (live) video(s) celebrating the 50th anniversary of Apollo 11 moon landing? If so, looking forward to it!

[@mikebronicki6978]

Live and on location please.

[@williammclemore5815]

Very good treatment on how the Apollo astronauts navigated to and from the moon. A bit above this old mind seeing as how I have never used a sextant. Still very informative and enjoyable for someone who lived during those glorious days.

[@miriamn9657]

Well...not quite. The CMC didn't have the capability to calculate the burns that 'brought the mission forward'. It just had a 'return to earth' program that could calculate an abort burn. Almost all burns during a mission were calculated on the ground by the RTCC (real time computer complex) in Houston. The CMC's only job was to control those burns. The whole other stuff came into play when contact with Houston was lost and even then the CMC wasn't mandatory to get home: Houston regularly provided the astronauts with PADs (preliminary advisory data) which gave them all the information they needed to do an abort burn by themselves, in last line of defense with not just more then a stopwatch, the COAS and two stars. In the end, the CMC was a backup to a backup and backuped again by the 'stopwatch method'.

[@ChristopherUSSmith]

Indeed. And there were all the "P00 and accept" uplinks of updated REFSMMAT and state vectors from the trench, too.

[@jdfletcher21]

So happy you are back!

[@harrykoppers209]

Minor thing- dead reckoning is a contraction of deduced reckoning, thus answering a question you never asked.

[@0623kaboom]

what would be a nice companion video to this one is to write a basic program that would take the various inputs and give a position answer to smack the sceptics upside the head that the program had to be too large to fit on any computer of that time

[@mnealbarrett]

Love all Vintage Space videos. BTW, disadvantage of using a wall as backdrop instead of your living room: no Pete photo bombs. :)

[@highlypolishedturd7947]

Good point. I'm not really a cat person, but it's hard to go wrong with almost any small, furry animal.

[@pauligrossinoz]

... I remember Pete in the background humping a cushion in earlier episodes ... that was funny! 😂

[@ChristopherUSSmith]

The WWW is for cats. 😺

[@ChristopherUSSmith]

@rusty nuts No doubt. ;)

[@Pygar2]

@@ChristopherUSSmith Wrong, sorry... kzbin.info/www/bejne/goWtp5d9mMdqfNU

[@briandenzer]

Just found your excellent presentations. Thank you. A little friendly advice: Slow down; don't race through the information; use pauses to give listeners an opportunity to process; do some personal voice training on how to use your diaphragm to control a column of air through your vocal chords so you don't achieve vocal fry and sound like you're tired or nervous.

[@ChristopherUSSmith]

Sorry to complicate it further Amy, but the AGC was technically the *backup* system. *ALL the trajectory computations were done by the engineers in the "trench", the front row in the MOCR.* See the _Moon Machines_ episode on the "Navigation Computer" to learn why.

[@ChristopherUSSmith]

All the "P00 and accept" requests of the crew by the CAPCOM uploaded updated REFSMMAT and state vectors into the computer, based on trench calculations.

[@APublius32]

Thank you for your videos. They are amazing, insightful, as well as informational. I especially enjoyed watching this video.

[@ConradSpoke]

Spaceflight knowledge is groovy!

[@gorillanobaka9772]

glad you're back.

[@RayRay-zt7bj]

I like the navigation system used in the Apollo 13 return flight to Earth. Keep the Earth in view through the window!

[@ChristopherUSSmith]

Lovell developed that on Apollo 8. Good thing he still remembered it 16 months later. :)

[@dougryan9973]

Amy.....when the Apollo missions were in the parking orbit right after launch, it was necessary to maintain correct roll, pitch and yaw attitudes prior to trans-lunar injection. Did the S4B have thrusters to help with this or was it handled by the trusters on the CSM? Did the astronauts do this manually with the attitude controller in the Command Module?

[@ChristopherUSSmith]

The S-IVB was for propulsion only. The CSM's RCS (thrusters) handled pitch, roll and yaw, as well as the transposition and docking with the LM when extracting it from the S-IVB.

[@tomsbeststuff2134]

Great new content! You can't talk about Apollo navigation without Jim Lovell!

[@eddieo4900]

Ms Teitel, you’re a lady and scholar to present us such eye opening details of Apollo. We must never forget that navigating to and landing men on the moon was a feat of grand proportions that took a monumental effort never to be equaled. Great history!! Please keep sharing!!

[@georgenemecek5653]

Too bad they erased the telemetry. Video tapes are so expensive!

[@67comet]

SOOOO happy to see you doing videos on Vintage Space again .. I know you probably had burnout so you are graciously gorgiven :) .. thank you again, interesting videos always ..

[@error.418]

She doesn't need anyone's forgiveness... No video producer on KZbin does.

[@perrythomas6971]

Nice to have you back!

[@Sarruji]

Is that KSP I hear in the background lol? Great video.

[@sundhaug92]

Not directly, KSP got their music from the same guy (who gives away his music for free)

[@Sarruji]

@@sundhaug92 Nice :)

[@apotheosis27]

Haha I noticed the same thing

[@Gitarzan66]

Its great to see a new video. I love your channel.

[@heater1blackbird130]

When the spacecraft was docked, the point of the command module was attached to the lem. Wasn't that where the parachutes were stored on the command module ??

[@ChristopherUSSmith]

The parachutes were not in that part of the CM. They were off to one side, in a compartment well below and further out from the "probe and drogue" top hatch where the LM docked. Look at any of the CM reentries and even the re-creation filmed in Apollo 13.

[@Whitpusmc]

Yay another VS video. Amy you are my favorite KZbinr.

[@samuelcoco4128]

Nice to see you back. Love the Apollo missions when I was a kid. Saw the Moon landing...

[@dukecraig2402]

Me to, earliest memory that I can place a date on, July 20th 1969, I was 4, my uncle worked at the Cape for Boeing and we just lost him a couple of years ago, just last week I got some of his personal belongings from relatives in Florida, a jewelry box full of medallions and rings from the Apollo missions and Shuttle missions including Magellan, he was also on the team that examined the recovered satellite from the Challenger disaster (Boeing had a defense department satellite on it), in the 70's when things were slow at the Cape he worked as a golf pro at a resort in Florida and there's a bunch of PGA stuff in it to like tie clasps and cuff links, being from a dreary old coal mining town in Pennsylvania he was like a rock star to me when I was a kid in the 70's, it was like having Dean Martin for an uncle.

[@davidstigall9328]

how can you tell speed in space when it is a vacuum?

[@w6wdh]

Integrate the acceleration and add the integral to the starting speed. In 3 dimensions, of course. Also have ground based radars measure spacecraft location, distance, and velocity.

[@ChristopherUSSmith]

That's the whole point of inertial guidance. If you keep track of your starting point and how much you move in every direction, you know where you are and how fast you're going... so long as you don't go into gimbal lock. :)

[@malcolmbacchus421]

And in addition to inertial guidance (there were redundant sets of accelerometers), and, if necessary, repeated start sighting, so long as you are in communication with Earth, you have the Doppler effect on the tracking radar and on the unified S band communications. In fact, the Doppler calculations - albeit complex enough that they could only be done by the RTCC and not the AGC - were so accurate they became the primary way of dealing with the determination. As said by others replying here, the AGC/sextant approach really became the backup not the primary method of calculating velocity and distance. The sextant and the inertial guidance system was really much more needed for ensuring the attitude of the spacecraft was correct for a burn: after all, it's pretty important when you light the engine to ensure you are pointing the right way.

[@agschwend]

Love your necklace. I saw them many years ago in Bogotá in the gold museum. The story behind them is so fascinating. Would be worth a video. I love your videos, you make them so well.

[@renejaxson8560]

Its refreshing to listen to a young women, who does not speak with "vocal fry" or "uptalk" .

[@ct6502c]

She actually does have vocal fry, but no upspeak, thank goodness. That whiney upspeak that all the Millennials have is what is really annoying.

[@WEM2016]

This is a thing humans did. No internet, no smartphones, barely anything in the way of precedence, so aside from refinement this was basically a shot in the dark, but look where it got us! So cool!

[@RideAcrossTheRiver]

Not a whit of what you said is true. Global networking, audio-visual radiotelephone, and upload-download all in play here.

[@Aviator27J]

Pilots learn some ded reckoning in initial flight training too. Don't forget us pilots! ;) I also learned it in some format while in wilderness survival training in middle and high school so I could navigate on the ground. Also, nice article in Astronomy magazine!

[@anthonytesta3716]

Hey Jay, dead reckoning in space. I need to know more. On earth easy, but in space? If you make a mistake see ya so long ..How can they do it?

[@mikimisko6753]

Nope, copilots didnt have same learning as pilot,.

[@anthonytesta3716]

Dead reckoning in space. Maybe short distances nope

[@jasonunwin5422]

1. I LOVE my Dyna Soar shirt. I get a lot of looks wearing it. ;-) 2. I guess you could call the computer on Apollo, "The Little Computer That Could". :-)

[@miguelencanarias]

Incidentally, Amy, how did NASA know where was the capsule to splashdown? The tiniest variation in trajectory at reentry would translate into significant distances, right? Was the splashdown position stablished at the start of the mission or during it? The calculations seem mindnumbing to me. EDIT: By the way, in case the wording of my question wasn't clear: I am NOT one of those imbeciles in tinfoil hats, peddling conspiracy theories about the Moon landings and whatnot. I'm honestly asking because I am in awe at the level of accuracy, planning and calculation involved.

[@robertvirginiabeach]

The command module could be steered to a limited extent by rolling it during reentry. Astronaut heads towards the horizon would curve the ground track to the side. Astronaut heads towards space vs the Earth could affect distance down range. The roll orientation could be changed as required during the reentry. Despite this there were still brief time windows for maneuvers like the engine burn for leaving lunar orbit. Any delay might make it necessary for the crew to wait for the next lunar orbit and the recovery force to rush to a different location while the spacecraft was in route.

[@malcolmbacchus421]

Mission control had a very good idea of where the spacecraft was and its velocity from radar and radio Doppler. This allowed MCC to uplink a final state vector some 4 hours before landing. The guidance computer then did the work although the astronauts could take over using the Entry Monitor System if necessary (or even other methods if that failed). In practice the computer did it all, every time. The broad landing point was determined by where and when you arrived back and the final midcourse correction took care of that. Whilst a final course correction refined the landing point before the SM was jettisoned, the command module was itself, to some extent steerable as it had lift and its own reaction control jets. In fact, for Apollo 11 MCC added some 300miles to their original splashdown point in order to avoid bad weather. Again, all done by the little Apollo Guidance Computer.

[@thedungeondelver]

@@robertvirginiabeach Interesting fact, the CM was actually designed as a lifting body! It could gain (and lose) altitude just in the manner you describe during reentry.

[@gabrielesimionato1210]

I've read in the official Press Booklet from NASA that a vessel returning from the Moon will splash more or less in the opposite side of the world from the point it enters atmosphere. Which, as everybody knows, is at exactly 70,000 km, right when the music stops.

[@malcolmbacchus421]

Gabriele Simionato Basically if you fire an engine retrograde, you will lower the perigee of the orbit exactly 180 degrees from where you fire it. The deorbit burn involves creating an elliptical orbit where the perigee hits the earth (that's landing), so the landing is 180 degrees from the burn. The actual landing point isn't exactly that on earth because of the atmosphere (in fact the atmosphere can make the capsule miss hitting the ground entirely, if the entry angle is wrong, by skimming off it). But very specifically, the design of the Apollo capsule, as we discussed, gave it the ability to steer slightly once in the atmosphere. Hence the statement you read.

[@ilRosewood]

I’d love to know more about what adjustments had to be made to this process for Apollo 13.

[@gokulmanohar5677]

I thought you aim at moon and the shuttle will get there. Never knew it was that complicated. Thanks..

[@ChristopherSmith-bh4sz]

Shuttle? No shuttle went to the moon only low earth orbit.

[@YQTFun]

Just read the book Carying the Fire by Mike Collins last week 😁 big part on navigation.

[@BaguetteGamingOfficial]

I just finished it 1 month ago , amazing book

[@MrGilRoland]

How Apollo astronauts didn’t get lost: Astronaut 1: “So where do we go?” Astronaut 2: *pointing the Moon* “There”.

[@BaguetteGamingOfficial]

*slow clap*

[@MrGilRoland]

*slower clap*

[@marionpettersson3774]

This answer one question I have had for a long, long time! Thank you a lot!

[@ramblerandy2397]

Great matter of fact video presentation. I'm assuming that inertial platform was all-analogue. And what a beautiful piece of engineering it was. Probably reduced to thumbnail size today.

[@0623kaboom]

yes ... it was .. there was once a video online talking specifically about the main gyro for navigation ... and how much it weighed ... something like an old portable sewing machine ... ok lugable sewing machine

[@RCAvhstape]

Modern gyro systems are solid state, I believe. Much smaller and lighter. But you gotta love the elegance of the Apollo Saturn system. Like a Swiss watch. A gigantic, 360 foot, 7.5 million pound thrust, 11 km/s Swiss watch, that shakes the earth like an atom bomb when it takes off and hurtles to the moon and back while never losing its style.

[@dukecraig2402]

Don't forget, it was an Inertia Navigation System in Korean Air 007 that wandered off course on September 1st 1983 leading to a Soviet fighter shooting it down, goes back to the saying we all used to use years ago, "They can put a man on the Moon but they can't ________" (fill in the blank).

[@malcolmbacchus421]

The IMU was analogue. The gimbal angles were converted into pulses by the Data Coupling Units and the pulses were the input to the guidance computer.

[@ramblerandy2397]

@@malcolmbacchus421 Fantastic. With microengineering , analogue still has plenty of uses.

[@rishabhvats6896]

She is the live example of beauty with brains !

[@w6wdh]

Great video, as always. One interesting point in the launch came at T minus 15 seconds. You can hear “Guidance is internal” on the voice track. The astronauts pointed their sextant at a fixed marker on the launch pad. At T minus 15 seconds, the guidance computer set the starting spacecraft location, orientation, and velocity, using the sextant. From then on, the accelerometers and gyros were used to extrapolate the current spacecraft location, orientation, and velocity relative to that starting point. I’ve always wondered about the math, though. The earth is rotating and orbiting the sun, so what coordinate system do you use? It seems to me you want to use an inertial reference frame, which makes sense in space. But then you have to keep track of the earth’s rotation and its orbital position, along with the position and velocity of the moon. And of course the earth and moon are circling together around their common center of mass. It’s complicated.

[@malcolmbacchus421]

Bill Holland Not quite. The call refers to the Guidance Reference Release (actually at T-17s give or take a bit). The AGC has little to do with this and the astronauts don't have anything to do. Up to that point the inertial guidance unit in the Saturn (not the CSM) is being torqued to keep it in line with the earth's rotation by the IU having taken its reference from the ground marker you mention. Effectively up to this point the guidance was being held to a rigid reference point. At Guidance Reference Release, the adjustment of the gimbals in the IGU is stopped and the gimbals allow to run freely maintaining their constant inertial orientation from that point (hence the word 'release'. This should have been done at the point of launch, but was done early to stop the jarring of the engine start up throwing the settings off alignment and was felt to be less risky that the small alignment error caused by stopping the updating 17s early. This was all automatic. The astronauts didn't have to do anything.

[@radioactive9861]

@@malcolmbacchus421 Fascinating!

[@narajuna]

Messy stuff, ship turns on itself, highspeed, its a curvy trajectory. Dont they need special optic to see stars? Miracle the first #8 got a bullseye :)

[@jacksonmacd]

I had always assumed that the sextant readings were only on stars. Interesting to learn that earthbound targets were also necessary.

[@chrischan5168]

So they flew into space and let the moon come to them... Genius!

[@chrischan5168]

@@JohnSmith-eo5sp Jesus.

[@SJSUPhilosopher-c1d]

Super!

[@cateclism316]

As a kid watching the Apollo program, I had no idea how complex this was!

[@nathanlewis42]

Could you do a video on the deep space EVAs in the later Apollo missions?

[@varuzhshakbazyan5732]

Those were filmed in a studio along with the moon walks. Spacewalks are so dangerous the rarely ever do them even on the ISS. You're gonna depressurize the ship 100,000 miles from the Earth? To retrieve tapes? It's crazy.

[@lowifrles9813]

Varuzh Shakbazyan quiet you G’damn communist.

[@joevignolor4u949]

@@varuzhshakbazyan5732 What's crazy about it? To study the moon they had placed high resolution cameras back there in the service module and before reentry the film had to be retrieved somehow. The astronauts simply put on their spacesuits, depressurized the cabin and one of them went outside to get the film. I've seen the video taken of these spacewalks and both the astronaut and his tether are obviously floating around weightless . What proof do you have that it was faked in a studio?

[@nathanlewis42]

Varuzh Shakbazyan don’t be an idiot. There’s a ton of evidence that they went to the moon including some presented on this channel. If there had been any doubt that the Apollo missions went to the moon the Soviets would have jumped all over it.

[@varuzhshakbazyan5732]

@@joevignolor4u949 The Eva footage could have been shot in low Earth orbit. There is no evidence that anyone has been to the moon. All of NASA's claims are suspect, their videos are fake, with the astronauts not doing anything in low gravity. Did any of them jump more than 1 foot off the ground? Did they do anything that would prove they were on moon? No. Here is all the evidence you need, go to flicker and pull up these : Apollo 17 magazine 134/B. Photos AS17-134-20383, 20384 and 20385. It's right there on flicker. The flag clearly has moisture on it, those photos were not taken in a vacuum. Water cannot exist on the moon in any form besides ice. Also, the flag is nothing special, it's not made of aluminum or Mylar or titanium. It's just a plain old cloth flag just like the one hanging everywhere in America. I would love to hear any explanation for how there can be moisture on the flag on the moon. If they faked those photos then the question is why? All they had to take a baseball up there and throw it. Or have one of them jump straight up like 6 feet off the ground. Did they do that ? No. Because they were always on the Earth.

[@j.t.thomas9242]

I wish I had you as a professor when I took space dynamics in college...you explain this insanely complicated topic so much better.

[@UTubeGlennAR]

>^. .^< Nice to have you/Vintage Space back. Hope PC is well.

[@brentdrafts2290]

Had a collection of Time and Life encyclopedias as a kid in the early seventies; one was about space and NASA. Very fascinating.

[@mizzyroro]

What's the plan for July 16, 1969? I plan to celebrate by performing the entire mission in realtime in Orbiter.

[@error.418]

Ah, was gonna say, 1969 is a long time ago, can't make plans for the past. But you mean the 50th anniversary, very cool. That sounds like a great plan.

[@brianhiles8164]

Your _putting_ analogy would have been perfect if you had also instituted the vagaries of topology to serve as metaphor for gravity [holes]. It is not to be forgotten that the ball (and tee) is moving too. And errant winds to be the subtle but constant solar wind?

[@zapfanzapfan]

We want Pete, we want Pete! :-) Otherwise, awesome as always! Maybe build the Lego lunar lander for the 50th anniversary?

[@easleyrider]

DAMMIT THIS CHANNEL IS SO GOOD!!!! You kick ass Amy!

[@dsc4178]

So basically like throwing a pass to a receiver on a post route on a windy day, but with more violence.

[@tetsujin_144]

Also the receiver is 380,000 km away and moving 1km/s

[@badguy1481]

Once the "off course" deviation was determined the astronauts oriented the space craft for the "Delta V" engine burn (Delta="change" V=Velocity). The space craft's center of gravity axis was reoriented to the predetermine direction of the burn. The engine was then "turned on" for a specific length of time in order to achieve the change in velocity needed to stay on course.

[@squatch545]

Hey Amy, would you consider doing a Livestream so we could ask you questions?

[@craigwall9536]

c'mon. she researches these videos; expecting her to ad lib in this kind of detail is just unrealistic. She's got a life- she's not a space jukebox.

[@squatch545]

@@craigwall9536 She has already done a livestream building a lego model kit. It's not "unrealistic" to ask for a livestream Q&A. No research involved. Easy.

[@craigwall9536]

@@squatch545 Easy for Legos. NOT easy for Astronavigation.

[@martshal]

You should do a quick explanation of how these same principles were used to aim the Apollo 13 capsule/lander back at earth after it went around the far side of the moon, and why it was necessary to manually "drive" it the way they did.

[@varuzhshakbazyan5732]

She can't because nobody has ever been to the moon.

[@rightlock2826]

I've played enough kerbal to know you wait for mun rise, burn prograde and just kind of eye ball it

[@nathanb011]

Right Lock or, alternatively, maneuver nodes.

[@ioresult]

Install Real Solar System and try that again!

[@kellingc]

i love your posts. You give a lot of good information that is easy to digest

[@horizonbrave1533]

not like putting?? but....in Kerbal, everytime I successfully land on Mun, I do a golf clap...

[@RCAvhstape]

Nice Scott Manley pronunciation. Fly safe.

[@donrimel7500]

A great companion video would be how Apollo 13 did the GNC without the command module functioning for a significant portion of the flight.

[@dosmastrify]

Seconded!

[@ChristopherUSSmith]

All the computations were done by the "trench", the first row in MOCR (Mission Control) and input by the crew.

[@joevignolor4u949]

Coming around the moon and heading back they used the guidance system in the LM, which had the programs stored in it to control both spacecraft together in an emergency. After that the LM's computer was shut down to save power and any burns had to be done manually. Once the CM was powered up again its GNC was used for reentry.

[@ChristopherUSSmith]

@@joevignolor4u949 True. The AGC was called the CMC in the CM and the LMC in the LM.

[@ml.2770]

Traveling through hyperspace ain't like dusting crops, boy! Without precise calculations we could fly right through a star or bounce too close to a supernova and that'd end your trip real quick, wouldn't it?

[@ChristopherUSSmith]

Said the fictional bounty jumper, smuggler and Rebel General Han Solo. ;)

[@larrysouthern5098]

No..LUKE.. I am your father!!! .....now come here boy and give your daddy a big hug!!!..oh and sorry about your hand......

[@kellyweingart3692]

lol

[@g-dogmoney]

Have a question. On Apollo 14, when the CSM docking collar had trouble latching onto the LM's docking target, how did the repeated attempts effect navigation? Great video and keep up the good work.

[@malcolmbacchus421]

Flyby Knight it must have done a bit, because it would have had some effect on the overall velocity but, given the speed both modules were travelling the small relative speed of the CM to the LM would have been tiny. In fact of the four mid course corrections scheduled for the translunar flight, both the first and the third were not needed. If there had been any significant effect of the docking issue you would have expected MCC-1 to have been required, but it wasn't. And MCC-2 was totally nominal (pre launch plan had it at GET 30:36:07 for 11.1 seconds with a delta-v of 74.4 ft/sec - actual was GET 30:36:07 for 10.14 seconds and a delta-v of 71.1 ft/sec.- given if anything the repeated docking attempts might have expected to slow the vehicle, you can the effect must gave been tiny).

[@Kuchenblech_Mafioso]

I was thinking Amy was talking about pudding. Slightly disappointed, but great video still

[@squatch545]

I love Vintage Space !!

[@cmdrterrorfirma4244]

Wow.. I never heard that the reason they went in internal guidance was so that the Soviets couldn't send disrupting signals to throw them off course! It is weird to think that was a reality back then, that they would consider it a real issue and threat! thanks for that great description of how they did it! I knew they used the scopes to measure angles and reset the nav computer but I had no idea how they did it.

[@SimplySpace]

Great video as always Amy!

[@GratiaCountryman]

What’s amazing is that they did this with an onboard computer that had less computing power than today’s smartphones.

[@ct6502c]

@@shiwomino5775 oh STFU, pathetic conspiracy theorist nutjob.

[@galacticus9845]

Another fascinating video from Amy.