The triumph and near-tragedy of the first Moon landing(arstechnica.com)
arstechnica.com
The triumph and near-tragedy of the first Moon landing
https://arstechnica.com/science/2017/12/apollo-triumph/
31 comments
If you want a great experience and have 15 minutes to spare, http://www.firstmenonthemoon.com/ has synced up the key radio channels, the video, and the transcripts of the radio traffic (with explainers for acronyms) in real time. I tense up every time as they hit the various go/no go calls.
I had the 15 minutes to spare. :)
The go calls as well as some other chatter feature prominently in the song Go! by Public Service Broadcasting: https://www.youtube.com/watch?v=BHIo6qwJarI (The Louis La Roche remix is also great.) The whole album is spaceflight-sample-themed.
The go calls as well as some other chatter feature prominently in the song Go! by Public Service Broadcasting: https://www.youtube.com/watch?v=BHIo6qwJarI (The Louis La Roche remix is also great.) The whole album is spaceflight-sample-themed.
That was pretty cool! Thanks!
Thanks for this!
Fun facts not mentioned in the article:
* The lunar module was off course because the astronauts failed to completely vent the tunnel between Eagle and Columbia and the resulting puff of air altered their trajectory.
* Apollo 10 was short-fueled to keep the crew from mutineering and attempting to land.
* Apollo 11 ended the crew's careers as astronauts: they were national and international heroes, and no sensible bureaucrat was willing to risk them.
* The lunar module was off course because the astronauts failed to completely vent the tunnel between Eagle and Columbia and the resulting puff of air altered their trajectory.
* Apollo 10 was short-fueled to keep the crew from mutineering and attempting to land.
* Apollo 11 ended the crew's careers as astronauts: they were national and international heroes, and no sensible bureaucrat was willing to risk them.
If you are interested in more details of the guidance and control system of the Apollo missions, I highly recommend the book Digital Apollo by David A Mindell.
Someone a while back on hackernews recommended the above book and it was absolutely fascinating and it's written remarkably well, very engaging. I am now a professional GNC engineer :) The book also delves into the gradual evolution of fly by wire flight controls starting with the X-15.
Someone a while back on hackernews recommended the above book and it was absolutely fascinating and it's written remarkably well, very engaging. I am now a professional GNC engineer :) The book also delves into the gradual evolution of fly by wire flight controls starting with the X-15.
This book helped explain a lot to me. I used to think that going to the moon was magic, but a lot of the stuff, like the lander module and the AGC, are straightforward implementations of the next steps from building guided missles, which the team had previously worked on.
That said the fact that they had a priority-based multitasking operating system running well enough to handle data overload conditions while maintaining real-time control of a spacecraft landing on the moon, is still damn impressive.
That said the fact that they had a priority-based multitasking operating system running well enough to handle data overload conditions while maintaining real-time control of a spacecraft landing on the moon, is still damn impressive.
An excellent book, which coincidentally I was reading last night.
I'd also recommend How Apollo Flew to the Moon by W. David Woods. Don't be put off by the slightly cheesy-looking cover - it contains a lot of fascinating technical information.
I'd also recommend How Apollo Flew to the Moon by W. David Woods. Don't be put off by the slightly cheesy-looking cover - it contains a lot of fascinating technical information.
So, so lucky we didn't kill anybody except the first three guys on the pad. There were so many opportunities to suffocate, poison, burn, freeze, strand, atomize, crush, or drown a crew. Their bravery, and the work of the engineers to get them home safe, is more stunning now than ever.
The cockpit transcripts are really worth a read. When I first read them they were interesting, but then I realized they were open loop. Aldrin is reporting instrument values he would want to know if he were piloting the ship -- but he's not looking out the window!. Meanwhile Armstrong is looking down out the window steering, assuming that Aldrin is telling him what he needs and so is asking little.
Those guys really practiced and really knew each other well. What a team!
The transcripts: https://www.hq.nasa.gov/alsj/a11/a11transscript_cm.htm
Also: I was a little kid and really excited by the moon landing, but couldn't appreciate how complicated it was. Later, as a teen, I figured it was pretty much pressing a button. But in my mid 30s I read these transcripts (and had an engineering education) and then saw a photo of Armstrong re-entering the command module after ascending from the moon. He was 37 at the time, about my age when I saw the photo. And the grin on his face... I'll never forget that.
Those guys really practiced and really knew each other well. What a team!
The transcripts: https://www.hq.nasa.gov/alsj/a11/a11transscript_cm.htm
Also: I was a little kid and really excited by the moon landing, but couldn't appreciate how complicated it was. Later, as a teen, I figured it was pretty much pressing a button. But in my mid 30s I read these transcripts (and had an engineering education) and then saw a photo of Armstrong re-entering the command module after ascending from the moon. He was 37 at the time, about my age when I saw the photo. And the grin on his face... I'll never forget that.
Oh, also, Russ Olsen does a wonderful talk about the moon landing and the engineering involved:
https://youtu.be/4Sso4HtvJsw
https://youtu.be/4Sso4HtvJsw
> Normally, in this time period, that is, from P64 onward, we'd be evaluating the landing site and starting LPD activity. However, the concern here was not with the landing area we were going into, but rather whether we could continue at all. Consequently, our attention was directed toward clearing the program alarms, keeping the machine flying, and assuring ourselves that control was adequate to continue without requiring an abort. Most of our attention was directed inside the cockpit during this time period and in my view this would account for our inability to study the landing site and final landing location during final descent[14].
> Nevertheless, Armstrong had time to notice that the LPD indicated "we were landing just short of a large rocky crater with very large rocks covering a high percentage of the surface"[15]....
This guy is pretty good!
> Nevertheless, Armstrong had time to notice that the LPD indicated "we were landing just short of a large rocky crater with very large rocks covering a high percentage of the surface"[15]....
This guy is pretty good!
First Man: The Life of Neil A. Armstrong by James R. Hansen is worth reading in its entirety if one is at all interested in this stuff. (Although it looks like they're making it into a movie for 2018.) It is a history written by an engineer who knew how to ask the right questions, which helps.
Always love seeing this, and recently watched a good film about the human computers who helped getting humans on the moon: Hidden Figures https://en.wikipedia.org/wiki/Hidden_Figures
More details on program alarms and other problems (eg. overcompensated throttle control, not fixed until Apollo 14): https://www.doneyles.com/LM/Tales.html
It's been 45 years since anyone has been more than 300 miles away from Earth. totally pathetic.
Well, there wasn't much to do up there.
Apart from the asteroids packed with precious metals or water/zero-g vacuum manufacturing /virtually limitless solar energy and near earth rendezvous from interstellar objects?
Reminds me of the speech that Nixon would've given had the Apollo 11 astronauts been stranded on the Moon:
"Fate has ordained that the men who went to the moon to explore in peace will stay on the moon to rest in peace.
These brave men, Neil Armstrong and Edwin Aldrin, know that there is no hope for their recovery. But they also know that there is hope for mankind in their sacrifice.
These two men are laying down their lives in mankind's most noble goal: the search for truth and understanding.
They will be mourned by their families and friends; they will be mourned by the nation; they will be mourned by the people of the world; they will be mourned by a Mother Earth that dared send two of her sons into the unknown.
In their exploration, they stirred the people of the world to feel as one; in their sacrifice, they bind more tightly the brotherhood of man.
In ancient days, men looked at the stars and saw their heroes in the constellations. In modern times, we do much the same, but our heroes are epic men of flesh and blood.
Others will follow, and surely find their way home. Man's search will not be denied. But these men were the first, and they will remain the foremost in our hearts.
For every human being who looks up at the moon in the nights to come will know that there is some corner of another world that is forever mankind."
http://www.lettersofnote.com/2010/11/in-event-of-moon-disast...
"Fate has ordained that the men who went to the moon to explore in peace will stay on the moon to rest in peace.
These brave men, Neil Armstrong and Edwin Aldrin, know that there is no hope for their recovery. But they also know that there is hope for mankind in their sacrifice.
These two men are laying down their lives in mankind's most noble goal: the search for truth and understanding.
They will be mourned by their families and friends; they will be mourned by the nation; they will be mourned by the people of the world; they will be mourned by a Mother Earth that dared send two of her sons into the unknown.
In their exploration, they stirred the people of the world to feel as one; in their sacrifice, they bind more tightly the brotherhood of man.
In ancient days, men looked at the stars and saw their heroes in the constellations. In modern times, we do much the same, but our heroes are epic men of flesh and blood.
Others will follow, and surely find their way home. Man's search will not be denied. But these men were the first, and they will remain the foremost in our hearts.
For every human being who looks up at the moon in the nights to come will know that there is some corner of another world that is forever mankind."
http://www.lettersofnote.com/2010/11/in-event-of-moon-disast...
And then there's Michael Collins's take:
> "My secret terror for the last six months has been leaving them on the Moon and returning to Earth alone; now I am within minutes of finding out the truth of the matter," he wrote. "If they fail to rise from the surface, or crash back into it, I am not going to commit suicide; I am coming home, forthwith, but I will be a marked man for life and I know it."
https://www.theguardian.com/science/2009/jul/19/michael-coll...
> "My secret terror for the last six months has been leaving them on the Moon and returning to Earth alone; now I am within minutes of finding out the truth of the matter," he wrote. "If they fail to rise from the surface, or crash back into it, I am not going to commit suicide; I am coming home, forthwith, but I will be a marked man for life and I know it."
https://www.theguardian.com/science/2009/jul/19/michael-coll...
Michael Collins' "Carrying the Fire" is by far the best of the astronaut memoirs (IMHO). Really well written!
Interesting; I'd seen that speech before, but hadn't spotted the deliberate echo of Rupert Brooke in the last line [1].
[1] https://en.wikipedia.org/wiki/The_Soldier_(poem)
[1] https://en.wikipedia.org/wiki/The_Soldier_(poem)
One of my questions was what the contingency plan for the astronauts actually was. From what I could find, it's only that they would stay in comms with NASA until the air ran too low, when they would end comms—shortly before suffocation. Then NASA would broadcast a burial rite by a select clergyman.
Is this the extent of it? Does anybody know if they were to suffocate, or if they had another option? Surely suffocating on the moon would be similarly terrifying to drowning isolated in the ocean. Sure the potential was known, and the reasons noble, but still...
Is this the extent of it? Does anybody know if they were to suffocate, or if they had another option? Surely suffocating on the moon would be similarly terrifying to drowning isolated in the ocean. Sure the potential was known, and the reasons noble, but still...
Dying of oxygen deprivation is actually one of the most peaceful ways to go. You just get drowsy, then pass out. The physical feeling of suffocation is caused by CO2 buildup in the blood, not lack of oxygen. So as long as their CO2 scrubbers worked, they could have just turned off the oxygen valve and drift off to sleep.
Thanks for the clarification. I was thinking of it as closer to holding one's breath/atmosphere leaving. I hadn't thought of it simply being an increase in C02 concentration.
It's not an increase in CO2 concentration. It's a decrease in O2 concentration. Humans can't actually sense low O2 levels, but instead only high CO2 levels.
I have always loved this letter.
I first learned of that speech from this xkcd https://xkcd.com/1484/
The fourth one always reminds me of Explorers We, written by Philip K. Dick in 1959:
https://d3gxp3iknbs7bs.cloudfront.net/attachments/42055afc4c...
https://d3gxp3iknbs7bs.cloudfront.net/attachments/42055afc4c...
To this day the stories of the moon landings are the greatest adventures in the galaxy.
To think that they hadn't had the tech to fake it...
To think that they hadn't had the tech to fake it...