Originally Posted by
Uplinker
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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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.