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As with all "current events in space", Scott Manley has an excellent video on this. https://youtu.be/cmQfWuFbLNg https://youtu.be/cmQfWuFbLNg

augusto-moura 6y ago
> Blowing a raspberry in the surface of the asteroid Classic Manley
- lolbot 6y ago
  From TFV: "In order to be able to perform the landing they needed to update their software to give it optical navigation abilities ..." Imagine being part of the team that had to do that, fast, chop-chop, or else their billion dollar space mission would fail miserably. "Oh, you only need us to implement vision. Ok, no biggie."
  - londons_explore 6y ago
    I assume it was more a case of "We have an algorithm that successfully lands the craft 80% of the time, but we would like it to be 99% of the time, so get to working on it..."
    - peterwoerner 6y ago
      Usually its 99.7% percent of the time: three standard deviations.
moron4hire 6y ago
"So they actually performed a software upgrade of on the spacecraft to give it optical navigation capabilities..." God dammit. And here I have trouble getting software updates into a server I have full control over on Earth.
- shadowgovt 6y ago
  Sadly, most of us don't have the luxury of working in environment where (a) it's mandated that we set up a 1-for-1 test rig with the production infrastructure and (b) management will accept the answer "I need to test for all possible contingencies because failure is not an option." (Most of us are writing code in an environment where failure is totally an option, as long as it's fast and restoration is quick ;) ).
  - moron4hire 6y ago
    Another part of the difficulty with updating servers is that updates are rather opaque. My own software on any given server is maybe 0.1% of all the software running on it (if even that). The other 99.9% is someone else's code: the operating system, the software runtime, the libraries, etc. So one doesn't really have a lot of insight into what is about to happen to the server without running a duplicate setup, which as you point out is pretty difficult to get right. I'm sure NASA has much more visibility into all the software that is running on their spacecraft.
    - manquer 6y ago
      While the abstractions is lesser for a spacecraft, I don't think any one is hand compiling or writing machine code directly. There will always be some abstraction layers.
  - bumby 6y ago
    While the requirement is there, often it falls through the cracks. A recent example is the wrong mapping of the Starliner thrusters. This wasn’t found until the simulator changed due to brownouts after it was already in orbit. Just by luck, the new simulator was of sufficient fidelity to catch the mapping error. Had 1) they not missed the correct orbit due to a different issue and 2) not had to switch simulators it could have potentially collided with the space station. So yes, the requirements are there but often not followed but luck was on our side
- BurningFrog 6y ago
  Then again NASA has a $22B budget.
Thorentis 6y ago
At 2:15 he discusses how NASA was completely wrong about the surface of the asteroid based on their initial thermal inertia analysis. While I don't pretend to be an expert, it's stuff like this that really makes me doubt how much we really know about distant parts of the universe. This asteroid is so much closer to Earth than many galaxies and other objects scientists claim to know something about. Of course, science is all about being wrong, refining the model, trying again etc. but my default reaction to any claim made about age/size/composition/distance, is immediate skepticism for this reason.
- zrkrlc 6y ago
  Well, we're entering the golden age of space exploration right now, so let's see how that gap closes by the next decade or so.

augusto-moura 6y ago

> Blowing a raspberry in the surface of the asteroid Classic Manley

lolbot 6y ago
From TFV: "In order to be able to perform the landing they needed to update their software to give it optical navigation abilities ..." Imagine being part of the team that had to do that, fast, chop-chop, or else their billion dollar space mission would fail miserably. "Oh, you only need us to implement vision. Ok, no biggie."
- londons_explore 6y ago
  I assume it was more a case of "We have an algorithm that successfully lands the craft 80% of the time, but we would like it to be 99% of the time, so get to working on it..."
  - peterwoerner 6y ago
    Usually its 99.7% percent of the time: three standard deviations.

moron4hire 6y ago

"So they actually performed a software upgrade of on the spacecraft to give it optical navigation capabilities..." God dammit. And here I have trouble getting software updates into a server I have full control over on Earth.

shadowgovt 6y ago
Sadly, most of us don't have the luxury of working in environment where (a) it's mandated that we set up a 1-for-1 test rig with the production infrastructure and (b) management will accept the answer "I need to test for all possible contingencies because failure is not an option." (Most of us are writing code in an environment where failure is totally an option, as long as it's fast and restoration is quick ;) ).
- moron4hire 6y ago
  Another part of the difficulty with updating servers is that updates are rather opaque. My own software on any given server is maybe 0.1% of all the software running on it (if even that). The other 99.9% is someone else's code: the operating system, the software runtime, the libraries, etc. So one doesn't really have a lot of insight into what is about to happen to the server without running a duplicate setup, which as you point out is pretty difficult to get right. I'm sure NASA has much more visibility into all the software that is running on their spacecraft.
  - manquer 6y ago
    While the abstractions is lesser for a spacecraft, I don't think any one is hand compiling or writing machine code directly. There will always be some abstraction layers.
- bumby 6y ago
  While the requirement is there, often it falls through the cracks. A recent example is the wrong mapping of the Starliner thrusters. This wasn’t found until the simulator changed due to brownouts after it was already in orbit. Just by luck, the new simulator was of sufficient fidelity to catch the mapping error. Had 1) they not missed the correct orbit due to a different issue and 2) not had to switch simulators it could have potentially collided with the space station. So yes, the requirements are there but often not followed but luck was on our side
BurningFrog 6y ago
Then again NASA has a $22B budget.

Thorentis 6y ago

At 2:15 he discusses how NASA was completely wrong about the surface of the asteroid based on their initial thermal inertia analysis. While I don't pretend to be an expert, it's stuff like this that really makes me doubt how much we really know about distant parts of the universe. This asteroid is so much closer to Earth than many galaxies and other objects scientists claim to know something about. Of course, science is all about being wrong, refining the model, trying again etc. but my default reaction to any claim made about age/size/composition/distance, is immediate skepticism for this reason.

zrkrlc 6y ago
Well, we're entering the golden age of space exploration right now, so let's see how that gap closes by the next decade or so.