Mars Science Laboratory/Curiosity

[Johno]

I have been showing my students

of the MSL rover, Curiosity, as it is hoped to operate.

Love it. But here\'s the question:

Is it overcomplicated?

[Guest Flixxbeatz]

not that complicated.

needs more kerbal in it.

[Arrowstar]

It\'s complicated, but only because getting a rover the size of a MINI Cooper down to the Martian surface is hard. The airbags approach that was used for MER is no longer possible with the weight of MSL, thus leaving rocket propulsion as one of the few available means to safely land.

JPL engineers are the best in the world at what they do: it\'ll work.

[Johno]

It\'s complicated, but only because getting a rover the size of a MINI Cooper down to the Martian surface is hard. The airbags approach that was used for MER is no longer possible with the weight of MSL, thus leaving rocket propulsion as one of the few available means to safely land.

JPL engineers are the best in the world at what they do: it\'ll work.

I agree with all of this except the simple confidence that it\'ll work - Yes, they\'re good, but is it possible?

[Ferrit]

It should work but Mars does seem to be a bit of a hard target; more than its fair share of probes and rovers have gone splat for various reasons. So I\'m confident that it will work but not going to be too surprised if, unfortunately, something goes wrong.

[Technical Ben]

Knowing Mars, she will throw up a storm like no other, and we won\'t even know if it landed till the dust clears.

[SteevyT]

Knowing Mars, she will throw up a storm like no other, and we won\'t even know if it landed till the dust clears.

He, Mars was a male god.

[Guest Flixxbeatz]

...so It\'s entirely a 'make-it-or-break-it' mission?

[NovaSilisko]

...so It\'s entirely a 'make-it-or-break-it' mission?

Technically every robotic space mission is like that. There\'s a really small margin for error.

That said, I expect the aeroshell/parachute combo to land right on top of the rover, trapping it forever.

[rdfox]

Technically every robotic space mission is like that. There\'s a really small margin for error.

That said, I expect the aeroshell/parachute combo to land right on top of the rover, trapping it forever.

Well, the engineers could accept that. After all, it\'s a failure mode that hasn\'t happened yet. They\'d be annoyed as hell, but at least it\'s a NEW failure mode! (Engineering mantra: 'Never the same failure twice.')

For that matter, isn\'t every *manned* space mission pretty much make-it-or-break-it? The margins for error are horrendously small, and even with people at both ends of the loop, you\'ve gotta be pretty damned accurate AND pretty damned lucky to have even 'successful failure' missions where you get the crew back with failed objectives. (Knowing the percentages... it\'s amazing to me that NASA flew 51 manned missions before losing a crew in flight, then flew another 81 manned missions before the next crew-loss accident. As was once pointed out, the Saturn-Apollo system, for example, was so complex that, even though it had 99.9% reliability for all parts, the odds are that there would be 1000 parts that would fail on any given flight... and the Shuttle system was a hell of a lot more complex than that! Yet, of the 11 Apollo missions, and the 11,000 part failures that probability would predict, only ONE of them resulted in a mission failure, and even that one was only a partial failure in that we got the crew back alive...)

[Hypocee]

Yet, of the 11 Apollo missions, and the 11,000 part failures that probability would predict, only ONE of them resulted in a mission failure, and even that one was only a partial failure in that we got the crew back alive...)

Apollo 1.

[Plymouth]

Well, you know that in KSP, unlike The Orbiter, you can fly to the mun without clean planning, just improvising, and still you can land and return sucessfully. I think it\'s gonna be the same thing with mars(or how will it be called) in KSP. You just have to get a nice orbit, and land, with a little bit of luck and skills.

So, in orbiter you had to count every second to land perfectly, unlike the KSP, when you can save the crew just in 1 km before crashing into the ground.

[Johno]

Apollo 1.

Doesn\'t count, they didn\'t launch it.

As for manned missions being make-or-break: one thing we tend to forget is that LEO space is pretty much the most hazardous environment humans have ever been in (the Moon was nastier, but only because of the tyranny of distance - presence of gravity made it a little easier to handle than LEO). I have a friend who works for NASA. He\'s now a flight director, but at the time I had this conversation with him, he was a controller responsible for EVAs. I asked him if the crew had ever had a 'bad hair day' and screwed everything up. He chuckled and said 'No, and it\'s a good thing - a \'bad hair day\' in an EVA would leave someone dead!'

Yes, space is dangerous. We forget because of the experience in handling it, but it\'s still deadly.

[Guest Flixxbeatz]

Technically every robotic space mission is like that. There\'s a really small margin for error.

From that standpoint, one can conclude that a single (or even a small) mistake can screw the whole thing up.

[rdfox]

From that standpoint, one can conclude that a single (or even a small) mistake can screw the whole thing up.

Remember the Mars Climate Orbiter of 1998?

Lockheed-Martin wrote the control software to operate in terms of Newton-seconds for RCS thruster performance. The NASA ground crew entered the data in pound-seconds instead.

As a result, instead of aerobraking at the intended 160 kilometers, it tried to aerobrake at 57 kilometers and disintegrated.

A single, small error. (The ground crew misread or failed to read the specifications for the data input.) Result: a $300 million unmanned probe mission down the drain as a bunch of glowing chunks of debris raining down on Mars, for exactly ZERO data returned.

http://en.wikipedia.org/wiki/Mars_Climate_Orbiter

[Guest Flixxbeatz]

Remember the Mars Climate Orbiter of 1998?

Lockheed-Martin wrote the control software to operate in terms of Newton-seconds for RCS thruster performance. The NASA ground crew entered the data in pound-seconds instead.

As a result, instead of aerobraking at the intended 160 kilometers, it tried to aerobrake at 57 kilometers and disintegrated.

A single, small error. (The ground crew misread or failed to read the specifications for the data input.) Result: a $300 million unmanned probe mission down the drain as a bunch of glowing chunks of debris raining down on Mars, for exactly ZERO data returned.

http://en.wikipedia.org/wiki/Mars_Climate_Orbiter

Yup. No room for error... definitely.

[rdfox]

Well, there\'s always a margin for error. MCO was supposed to aerobrake at 'between 150 and 170 kilometers' perapsis, and the engineers said that it could survive down to about 80 kilometers. But 57 was way the hell beyond its limits, and unsurprisingly, it died a horrible death.

It\'s not that there\'s NO margin for error... it\'s just that they\'re horrendously narrow (for example, a true free-return trajectory from Earth to the Moon and back is a corridor only 0.1 m/s wide, at TLI--literally equivalent to splitting a human hair, lengthwise, with a thrown razor blade at a distance of one mile) and the environment is extremely hostile if you exceed those margins.

If there was NO margin for error, we\'d never have left the atmosphere. (Remember those thousand part failures that were to be expected on any given Apollo mission?)

[Spacecats!]

Yup. No room for error... definitely.

My first ship to the mun had one if its 3 boosters explode, and I still made it and back. Noap, failure doesn\'t matter in some situations. :3

[AD-Edge]

Its definitely ambitious, and I also worry about how much more complex this one is in terms of both the landing and operating on the surface, but it seems necessary.

It could land fine of course, and then have some kind of other issue or damage from the landing.

If you want to have a look moreso at the statistical side of it, NASA has had a lot of success in the past couple of years with Mars related missions. I found this the other day which illustrates every Mars mission and its resulting success/failure:

It will definitely be and exciting and nervous time come next August.....

*Edit*

I was also going to note that in the case of a failure, it wouldnt be as expensive or time consuming to build another MSL rover, since the design for it is already down, theyd just have to modify/fix whatever issue arose, and then rebuild a new one. I dont know if this would actually happen, it would be devastating for this mission to fail, but I would hope theyd try again asap.

Either way, Curiosity is so important atm it really needs to succeed.

[Gojira]

sexy

[mincespy]

not that complicated.

needs more kerbal in it.

It needs to have a SRB on the back to go faster!