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Good wikipedia list, thanks. So, moon landings where the craft suddenly and unexpectedly lost comms in the seconds or minutes immediately prior to contact with

Good wikipedia list, thanks. So, moon landings where the craft suddenly and unexpectedly lost comms in the seconds or minutes immediately prior to contact with the surface: Government: 1 of 25 (4%) Commercial: 3 of 3 (100%) I'm saying it's odd, weird, and deserves investigating specifically from the angle of why commercial has this happen, but not government. I'm saying this because it is odd. I've not once mentioned conspiracy - though others seem ready to jump to that, probably as a subtle ad hominem instead of engaging with the discussion. Thank you for engaging, it's an interesting topic.

krisoft 3y ago
But is it odd? It is just a very hard problem. You need to spend a lot of resources to get it right and you need to spend them in the right way. Also you need to build up to the capability step by step. You can't drum random engineers together and expect them to build a lunar lander. You need to give them progressively harder and harder challenges, and see if they develop the right chops to handle them. What do you want to investigate? I'm sure the commercial entities did their own investigations about their failures and the factors behind it. They are under no obligation to share anything with me or you.
- detrites 3y ago
  It is indeed odd to me, that the only and all three missions distinct by funding all failed in exactly the same way, at exactly the same point, where those funded from a different source only did 1 in 25 times in that way. Perhaps the randomly-drummed up engineers argument could have some merit for overall mission failure, though it doesn't adequately explain failure on only the same, final mode. Were the same engineers involved? If so, it seems beyond the pale they didn't learn anything? To be clear, it's not that these landers hit the moon and expired, they all stopped transmitting on the final leg. It's a weird failure and even weirder that it wasn't experienced more frequently in govt funded missions. I've no plausible theory why, that's why it's interesting. All reasonable explanations have to be a bit out there, other than the de facto "bad luck", which doesn't wash with me. I'm not interested in investigating (beyond doing sums on wikipedia numbers). But I am interested in it being investigated by someone more qualified.
  - krisoft 3y ago
    > I've no plausible theory why, that's why it's interesting. These are groups on a shoestring budget trying to do something very hard for the first time. They fail at the hardest part of the task. How about that as an explanation? > All reasonable explanations have to be a bit out there, Have you tried hard things before? Failure is the default outcome. > they all stopped transmitting on the final leg That tends to happen when you hit a rock the size of the Moon. As these did. I think you are making a mystery out of this where there is none.
    - detrites 3y ago
      They didn't lose contact on impact, but minutes prior. The hardest part is the landing, not necessarily specifically the communicating with the lander on the way down - which in some sense is trivial depending how it's done. Indeed, it's an assumption they didn't land and instead impacted, until confirmed visually - as the landing is typically an automated process at that point. Continually breezing past the points I've made does nothing to convince me this isn't odd or interesting. I've no horse in the race and will continue to be intrigued until someone can give better explanations, rather than "it's hard dude".
      - krisoft 3y ago
        > Continually breezing past the points I've made does nothing to convince me this isn't odd or interesting. I’m sorry that it feels like that to you. I’m doing my best to adress your points to the best of my abilities. If you feel I am breezing by your point that just means I haven’t understood you yet. > They didn't lose contact on impact, but minutes prior. I see what you are saying, but that is not true. The Hakuto-R Mission 1 reports they have telemetry about the craft free falling. They talk about an altitude measurement system possibly miscalculating. They also talk about the thruster running out of fuel. [1] The Beresheet had an Innertial Measurement Unit fail, then they had communication issues, and they regained communication, but by that time it was too late to save the lander. They also had telemetry up until the impact if I read it right. [2] Which one is the third you are refering to? 1: https://www.reuters.com/technology/space/japans-ispace-prepares-worlds-first-commercial-lunar-landing-2023-04-25/ https://www.reuters.com/technology/space/japans-ispace-prepa... 2: https://en.m.wikipedia.org/wiki/Beresheet https://en.m.wikipedia.org/wiki/Beresheet

krisoft 3y ago

But is it odd? It is just a very hard problem. You need to spend a lot of resources to get it right and you need to spend them in the right way. Also you need to build up to the capability step by step. You can't drum random engineers together and expect them to build a lunar lander. You need to give them progressively harder and harder challenges, and see if they develop the right chops to handle them. What do you want to investigate? I'm sure the commercial entities did their own investigations about their failures and the factors behind it. They are under no obligation to share anything with me or you.

detrites 3y ago
It is indeed odd to me, that the only and all three missions distinct by funding all failed in exactly the same way, at exactly the same point, where those funded from a different source only did 1 in 25 times in that way. Perhaps the randomly-drummed up engineers argument could have some merit for overall mission failure, though it doesn't adequately explain failure on only the same, final mode. Were the same engineers involved? If so, it seems beyond the pale they didn't learn anything? To be clear, it's not that these landers hit the moon and expired, they all stopped transmitting on the final leg. It's a weird failure and even weirder that it wasn't experienced more frequently in govt funded missions. I've no plausible theory why, that's why it's interesting. All reasonable explanations have to be a bit out there, other than the de facto "bad luck", which doesn't wash with me. I'm not interested in investigating (beyond doing sums on wikipedia numbers). But I am interested in it being investigated by someone more qualified.
- krisoft 3y ago
  > I've no plausible theory why, that's why it's interesting. These are groups on a shoestring budget trying to do something very hard for the first time. They fail at the hardest part of the task. How about that as an explanation? > All reasonable explanations have to be a bit out there, Have you tried hard things before? Failure is the default outcome. > they all stopped transmitting on the final leg That tends to happen when you hit a rock the size of the Moon. As these did. I think you are making a mystery out of this where there is none.
  - detrites 3y ago
    They didn't lose contact on impact, but minutes prior. The hardest part is the landing, not necessarily specifically the communicating with the lander on the way down - which in some sense is trivial depending how it's done. Indeed, it's an assumption they didn't land and instead impacted, until confirmed visually - as the landing is typically an automated process at that point. Continually breezing past the points I've made does nothing to convince me this isn't odd or interesting. I've no horse in the race and will continue to be intrigued until someone can give better explanations, rather than "it's hard dude".
    - krisoft 3y ago
      > Continually breezing past the points I've made does nothing to convince me this isn't odd or interesting. I’m sorry that it feels like that to you. I’m doing my best to adress your points to the best of my abilities. If you feel I am breezing by your point that just means I haven’t understood you yet. > They didn't lose contact on impact, but minutes prior. I see what you are saying, but that is not true. The Hakuto-R Mission 1 reports they have telemetry about the craft free falling. They talk about an altitude measurement system possibly miscalculating. They also talk about the thruster running out of fuel. [1] The Beresheet had an Innertial Measurement Unit fail, then they had communication issues, and they regained communication, but by that time it was too late to save the lander. They also had telemetry up until the impact if I read it right. [2] Which one is the third you are refering to? 1: https://www.reuters.com/technology/space/japans-ispace-prepares-worlds-first-commercial-lunar-landing-2023-04-25/ https://www.reuters.com/technology/space/japans-ispace-prepa... 2: https://en.m.wikipedia.org/wiki/Beresheet https://en.m.wikipedia.org/wiki/Beresheet