Yep, Just seen comment attributed to the CEO that in the moments before touchdown the vehicle had a higher rate of decent than planned and also a small horizontal rate (it should have had none)…

Ever tried to land downhill ? the first time landing in mountain strips can be entertaining. I prefer to land uphill in any wind .
At least they cannot blame the landing on a crosswind .

Forgive my simplistic question, but as the lander was designed to be unmanned and remote and allowing for various negative possibilities/scenarios that might occur, why was this scenario not considered and a planned strategy implemented ? Even now side mounted booster jets might have had a rescue possibility, though it would need some pretty good synchronisation to avoid toppling over in the opposing directions. As I understand things, the lander will have almost no relevant functional ability in regards to it's mission as things (don't) stand..

One big negative was the mission lidar was (so far claimed) launched with the manual ground safety override in place so it could not function at all. I don't know if this merely blocked the laser beam from escaping or left it so it could not be powered. It was to prevent eye damage to technicians during checkout procedures. There was an experiment on board that also had a lidar system which they wrote a hack to communicate between the landing software and the experiment. A small amount of money on the chance the experiment lidar wasn't aimed in quite the same way and the landing software patch didn't make up the difference.

Surprising was the defect was noted only because someone apparently was curious to see what the readings were 2 hours before the mission lidar was needed. That made for a really short patch window.

There have been proposals to put up a navigation satellite constellation around the moon like the GPS or Galileo systems. This would have greatly aided the detection and cancellation of the sideways movement during landing. It might not require more than 4 or 5 satellites to do so as the landing could be specifically timed for when the nav satellites were visible. I think there is also a need for one ground station to calibrate the orbital information.

'Learning to fly R/C Helicopters back in the 70's having the machine topple over on landing was extremely common for all resulting in the end of your day's flying.
A very simple solution was to tie/tape two sticks about 1m long in a cross to the underside of the landing skids. With this you could still impact the ground with about 45 degrees of bank and a sideways drift and the thing just settled itself back on skids.
I am very surprised that there appears to have been little consideration for Odysseus not touching down perfectly? Simple solutions were available?

The possibility of a sideways component existing during landing, and the probability of rocks being around on the surface must surely have been considered.

So how to mitigate it? If accelerometers on the craft, integrated to provide sideways movement feedback would not suffice, then how about dropping a laser reflector to the surface from the craft before it landed to provide a static reference point on the surface for the craft to lock onto ?

Maybe this is what the LIDAR system was supposed to do, but do I understand that it was switched off or disabled to protect technicians during testing ?

Surely NASA uses checklists to ensure everything has been prepared and made fully operational before the craft is loaded onto the rocket and launched ?

"top-notch engineering" is being trumpeted, but I would dispute that.

How much did this mission all cost, only for the craft to fall over on landing ? It just beggars belief.
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Yes, indeed. The investors begin to react (as I would too): https://finance.yahoo.com/news/intui...105138570.html

The US stock market isn't open yet so that's 'out of hours' trading, which isn't always representative of what happens when it does open.

There are (conservatively) thousands of failure modes for a complex automated space mission. Addressing each of them with 'simple' mechanical solutions would add up to a very large increase in weight. As a starting point, the launch platform is set by the budget for the mission and the delta v requirement is fixed. This sets the maximum weight and dimensions of the spacecraft. Once you add in the basic mechanical components and the science components (which would have been set in the tender) your opportunities to add redundancy through additional mechanical components (rather than improved control software) becomes very limited indeed. I'm sure that a great deal of thought was given to this type of failure at the design stage but it is much easier to see the solution when you know what went wrong and don't have to work to the design constraints. The design challenges of building this type of spacecraft to a commercial budget are immense; it is still a very impressive accomplishment.

Landing with a horizontal component was not considered because due to the moon's low gravity and the spacecraft's inertia, almost any sideways component would result in a topple. As has been said the major fault is that a preflight checklist item has been missed. The LIDAR could not be switched on. They found out early because they wanted to use it to measure and correct their insertion orbit. They created a hack to use one of the independent payloads own built in LIDAR, however with any hack it's never as good as the original and there was some lag between reading, action and feedback. To be honest I'm amazed they got it down in one piece after that.
As for NASA, this is an independent, commercial operation, from launch (SpaceX) to touchdown. NASA did provide some funding but it's mostly private money. NASA was not responsible for this mission at all. In addition if you compare the cost of the first Surveyor mission to land on the moon, that cost in today's money about $5B, this cost a tiny fraction of that.
So, no, I don't think it does begger belief.
A private company has landed on the moon at a fraction of previous costs, lessons will be learned and progress made.
Rocket surgery is hard.

On a spacecraft, nothing is simple.
How big and heavy would those two sticks have to be to make this work on this spacecraft? How would they fit in the rocket fairing. They would have to be hinged or articulated in some way. A failsafe mechanism designed tested and built to extend them before landing. Then you would have to land in an area that was completely flat over an even wider area, one of those sticks hitting a big boulder during even a vertical descent would tip the craft over.
Rocket surgery is hard.

Agree very much with Recc's final comment:

"The design challenge of building this type of spacecraft to a commercial budget are immense; it is still a very impressive accomplishment."

There's a lot of talk of NASA should have done this or done that but in simple terms NASA contracted out the flying and landing bit to the commercial sector:

CLPS

Some things are simple, even when building spacecraft. Add a hinge at the base of each leg and a simple mechanism, in zero gravity rubber bands would be sufficient, to extend them once on the way to the moon. Worked perfectly well 58 years ago with Surveyor 1 (https://www.honeysucklecreek.net/oth...ay_26_1966.pdf). Even the Chinese patent, and they seem to be the only ones remaining who still master the art of landing things on the Moon successfully, has expired, so could have been used (https://patents.google.com/patent/CN102092484B/en).
But of course, if you want to reinvent the wheel by building a spacecraft with a very high centre of gravity and a narrow landing gear, spaceflight suddenly becomes difficult again.

“But of course, if you want to reinvent the wheel by building a spacecraft with a very high centre of gravity and a narrow landing gear, spaceflight suddenly becomes difficult again.”

As I understand it most of the upper structure on Odysseus was light weight so how high was the CoG and probably more importantly what were the tilt limits?

That said I think an increasing number of eyebrows are going to be raised at the proposals for the Human Landing System (HLS) on Artemis, and maybe also any thoughts that the landing on that system can be completely handed off to automation with no facility for manual reversion.

Does this rubber remain flexible at absolute zero temp? How does it react in direct sunlight? Like I said it all needs testing and it needs to fit in the budget. Any extra mass it adds will either mean more propellant is required or more performance from the engines. Or you ditch some of the science payload, which then means you've lost income from the payload customer, more budget constraints.
There is a very good reason whu Surveyor and Odyseus are different shapes, Surveyor didn't need to collect sunlight from a very high/low polar attitude, Odyseus did/does. A tall design allowed the solar panels to be mounted vertically, orientated in the best position to catch the most sunlight. No extending solar panels with complex unreeling or deployment required. Very simple just stick em on the side of the spacecraft.
All spacecraft are a compromise.
Edit, thanks for the link to the Surveyor mission. I couldn't find any references to rubber bands, only pyrotechnics and aircraft style shock absorbers, no wonder it was so expensive. 😁

Tilt is one thing that will throw your spacecraft on it's side, but much more important is a horizontal residual motion upon touchdown. Lunar gravity, the force that will hold it down, is only 1/6 of what it is on earth, but momentum, or the force (not a force in the true physical sense but for simplicity I will call it that) that will overturn it due to residual motion, remains the same. So one could say that it is six times as easy to overturn a lander on the moon than on earth. But certainly the guys who designed this thing knew about that.

I wrote "rubber" as a simple example, comressed gas (already present on the spacecraft), metal springs or pyrotechnics (which are not really expensive compared to the total cost of such a mission) would have done the job as well. And yes, these thigs add a little mass to the structure, thereby reducing the payload. As it is now, we have the maximum payload but lying horizontally on the moon, and therefore totally useless. Maybe they should have left those 125 stainless steel statues behind and installed a leg-spreading mechanism instead. But who am I to cosult spaceflight startup companies...

As the best part is no part, complex leg components were deemed unsuitable for this craft.
I know nothing about statues. Who paid for them? Was that a way to raise funding?

Here: https://news.artnet.com/art-world/je...ysseus-2440372
It seems they want to capitalise on these statues by selling NFTs.

Spaceflight should broaden the horizon of mankind. Not make rich people richer. But who am I to consult mankind...

Interesting point....now talking of high C of G's and landing gear any thoughts on Space X Starship as the lander for Artemis..............................................

https://www.nasa.gov/reference/human-landing-systems/