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Comment by zymhan | Hacker News Reader

It really puts into perspective what good job NASA does at what many call a "boring" mission.

NASA's Mars Polar Impacter, er, Lander, also shut off it's descent engine too early, believing it was on the ground, and slammed into Mars. This stuff is hard. The Wikipedia entry gives the details:

https://en.wikipedia.org/wiki/Mars_Polar_Lander#Landing_atte...

They don't have altimeter's/range finders?

I wonder what causes the confusion.

They do have radar altimeters, but radar altimeters face occasional issues. So they usually also bake in various failsafe measures. Sadly the failsafe measures tend to be the thing which dooms spacecraft, usually in odd ways unpredictable until an actual spacecraft is hurtling towards the ground.

That is too bad. I wonder if a laser in the front would be useless as the heat build up as it enters the atmosphere would make the "bounce-back" hard to receive.

I think a space program that has lost a Mars-bound spacecraft because different engineering teams could not decide on if they are to use metric or imperial units of measurement has nothing to gloat about.

It's not gloating, it's just pointing out that ESA has failed repeatedly where NASA has had repeated success. No need to take it personally.

It seems like ExoMars spent years shopping around between the US and Russia for launch, and major budget problems, which caused it to be redesigned more than once. I guess NASA doesn't usually have problems like that? https://en.wikipedia.org/wiki/ExoMars#History

Considering NASA has a budget thats 3-4x that of ESA, I'd be a little less quick to judge if I were you.

> Considering NASA has a budget thats 3-4x that of ESA, I'd be a little less quick to judge if I were you.

I don't think GP was judging ESA. I think they were merely pointing out how impressive NASA's success rate has been lately.

Truth, its especially commendable that most of their projects keep soldiering on well past EOL.

Not to take away from that but I suspect that there are a lot of good reasons to underpromise and overdeliver. I also wonder to what degree budgeting has something to do with it. Budget for a shorter lifetime given that you can usually end up extending missions if the equipment is still operational.

Not to take away from the great work of NASA engineers but EOL is kind of a misleading term when it comes to space science missions. At lot of mission end times are based off of funding and the lowest level science goals of the mission. While those are being completed they gather a case for continuing the mission and usually get it. Of course the main cost is getting the stuff there in the first place so why not add a relatively small amount to make it last?

No, but given the short lifespan of these things due to radiation, literally other-wordly conditions, and the fact that you can never repair it, the fact that a rover on Mars can last a decade is a technical marvel.

You also have to pre-program the entire flight and find out half an hour later if your parachutes and retro-rockets deployed, or you made a relatively small crater.

Fair enough. How about the UK's Open University that was marginally more successful with Beagle 2 for £66 million.

It went riding on another orbiter, Mars Express, but at least reached the surface intact.

They're spending 1.4B on the two ExoMars missions (and that's not counting the Proton rockets, which Russia's contributing).

NASA's budget is larger, but they're doing more missions (and spending a lot on SLS and James Webb). I suspect blaming the ExoMars crash on budget is inaccurate.

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