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The Forgotten Huygens Experiment
jdray writes "An experiment onboard the Huygens probe didn't run as planned because someone forgot to turn it on. The team lead for the experiment has put eighteen years of his life into the project, just to watch it not happen after a seven year ride to its destination on Titan."
not true, the probe didn't have enough battery power and memory to be able to send all data it collected over one channel.
It would have run out of memory in the descent and if it had had more memory it wouldn't have had enough time to send it all because the probe ran out of power after about 45 min. on the ground. The descent itself took 2 hours so there is no way it could have send all that data over one channel.
You are confusing bad luck with incomptence. it would be bad luck if the system failed when told to activate. It's incomptence if they left the activation codes out of the system. This is a case of the latter, not the former.
Many of us downloaded and listened to the audio of the probe falling through Titan's atmosphere... could it be possible that processing the audio with known things such as downward velocity of the probe and assuming what it was flying through was methane (or whatever hypothesized atmospheric makeup), etc could yield similar wind speed estimates?
They would have to have very very good thermal insulation.
... the fluid involved is methane, a simple organic compound that can exist as a liquid or gas at Titan's sub-170C temperatures ..
From what I have heard, this is one of the reasons the probe had such a short lifespan, batteries don't last long at these kind of temperatures.
I suspect that this would make even a rover type robot quite a difficult challenge.
Let's practice:
Me: "'Duh' and 'doh' are not the same thing, duh!"
You: "Doh!"
You know, if I were this guy, I would have been calling them once every five minutes saying, "Hey, did you remember to get my experiment going?" If it's really that important, why let someone else screw it up for you? It's your baby, your responsibility.
"Give a man fire, and he'll be warm for a day; set a man on fire, and he'll be warm for the rest of his life
This is what the slashdot post says...
But I got this out of your linked article...
And I also found this article online. Here's an excerpt...The reports are confusing and I can't tell what happened. Was there a measurement device onboard the Huygens probe gathering data and transmitting it (like the Slashdot story suggests), or was the data supposed to come from the measurement of the signal from the Huygens probe in relation to the Cassini orbiter?
If it was the former, is the data not as good because the Earth radio telescopes didn't pick up the entire signal, because there was signal degradation, or because they have to piece all the data together from all the different radio telescopes? If it was the latter, is the data not as precise because of the proximity from the transmitter to the receiver?
Either way, the Slashdot post is wrong. If it was a measurement device solely on the Huygens probe, it was turned on- it was the relay onboard the Cassini orbiter that wasn't turned on. If the data was meant to be gathered from the proximity of the transmitter to the receiver, then the experiment wasn't onboard the Huygens probe but was actually meant to be a collaboration between the probe and the orbiter.
While I agree with the majority of your post, I think some of the expectations you place on ordinary software are a bit unrealistic. That is, in part, why daily use software is written differently than critical-systems software.
It's always a balance between the probability of a given failure, the concequences of a given failure, and the cost of adapting to that error. Different types of projects have different ways of looking at this balance.
What are the chances of a HDD being removed (or totally failing) while Photoshop is being used? Let's say... 1 in 10 million. What is the concequence? Worst case, 8 hours of work. What is the cost of anticipating such a failure, and dealing with it gracefully? Significant (You'd have a better idea of the man-hours involved than I would).
Now, compare that with how it handles a corrupt data file. What are the chances that a file you open isn't properly formatted? Uncommon, but it does happen... 1 in 1000, give or take an order. What is the concequence? Person can't do their job. What are the costs involved for dealing with a bad file? Significant, but not huge. Apparently it was worth it, because PhotoShop can read some non-standard formats, and fails gracefully with all others.
In the case if critical embedded systems, things are quite different. The chances of something going wrong are still fairly small... 1 in 100,000 say. But the concequence is the loss of life, which is very, very important. It becomes easy to justify the extra expense of writing systems that can handle these situations.
Adding fault tolerance for events that occur outside the software can dramatically increase the scope of requirements, and thus increase development time and cost. In most day to day situations, you have to balance your cost and your feature set. In day to day software, the return on investment for this kind of development has a near zero return on investment, and would be a bad business/project management decision.
~D
This sig has been enciphered with a one-time pad. It could say almost anything.
Believe me, you have been trolled.
This guy is an ass. I've never heard anybody in Canada (where I've lived all my life) say that we are "Real Americans" because we live on a continent called "North America". Nor do any Canadians particualarly care that the "United States of America" uses the word America in the name of their country.
It doesn't surprise me that this guy is from Quebec. It's a province full of weirdos, whiners and fascists.
Additionally, it's well known that the people in Quebec speak some kind of pig-french (a little harsh perhaps) that nobody else can understand.
I'm not a nerd. Nerds are smart.
However, I don't know if I really want software companies making desktop software fault tolerant to things such as the hard drive being removed.
Agreed, however I think we're talking primarily about mission critical systems in this case...situations where lives can be lost, or big bucks wasted. Not switching on the system, is pure incompetence...heads should roll (or maybe I need to RTFA).
As a defense contractor, our customers usually have high expectations (and rightfully so), though it may vary depending upon the application. Our bugs reports are prioritized, and some customers demand that we have no Pri-1 or 2 (out of 5) bugs at delivery, which requires alot of testing, time, and budget. The area where I see us getting burned most often is when management wins a contract based upon promises to deliver something way to quickly (but we couldn't have won the contract otherwise)...very common in the industry. It's a constant struggle between engineering and management...we know we need to win the contracts, but we also want to do the job right.
Just another day in Paradise
Mishaps like these are what make me grind my teeth when thinking about NASA and the space program. I've always been a staunch supporter of the space program, but failures like these make me question their value. How could however many dozen PhD's who spent 18 years FORGET to turn on an experiment like this? You'd think there'd be an if (module.enabled) {} check somewhere in the code that would throw a master alarm in the else {} clause.
This is why Burt Rutan et al. will continue to succeed: failure is not an option! If you forget to enable a system that cost millions of dollars, you're out of business.
Not that the mission is a total loss. But I'm still baffled by how NASA can make these mistakes. They're the type of mistakes that give some credibility to the conspiracy theorists, arguing that NASA didn't really lose the Mars Observer, the Polar Lander, or the Mars Climate Orbiter. Rather, NASA found evidence of extraterrestrial life and is covering it up. We probably won't know until the second space race heats up, with China, India and perhaps Brazil, but also Rutan, Branson, Bezos, et al. gunning for the moon and Mars. Onward!
Actually the french from Quebec could be refered as Royal French from the King's Court.
When France colonized North-America several folks from across France spoke french but a different dialect. (ex: southern france, northern france etc..etc)
In order for these colonizers to speak to each other the King decreed that the French spoken in the Royal Court will be used to communicate in New France so that everyone could understand each other.
France abandonned the colonies in North America to the english or sold land to the USA. (louisianne)
We all know the rest. Off with their heads in France.
The Bourgeoisie (spelling?) rose to the top of the food chain in France and of course established different laws. The French from France is Bourgeois. (Common french)
Meanwhile in Canada little has changed the french is derived from the Royal Court.
Which one is the correct french? They are both different and rich in expressions.
As people saying that the people in Quebec use more english words than in france, that is pure bullshit.
quick example:
Someone from France will say "Bon week-end"
Weekend is an english term.
It is used commonly in France.
Most Quebecers will say "Bonne fin de semaine".
As you can see, the French from France are getting lazy thru the years just like some terms in the French Canadian language. The advantage in Quebec is that people there can write laws that promote the correct use of the language and also on immigration so that they do not lose "la langue francaise".
on this note,
Passez une belle fin de semaine!
P.S. Sorry from grammar and spelling.
It's his experiment... etc Take more responsibility for it ! Make sure what needs to be done gets done ! Reminds me of two things: Ariene 5 rocket which blew up because Ariane 4 software was installed instead of 5. Buildings which get build be construction workers. A good architect will visit the site everyday to make sure everything gets done right and mistakes get corrected before it gets worse etc ;)
I've heard at least three claims to be the "best" French:
Quebec, because they use the fewest anglicismes (thanks in part to the Office quebecois de la langue francaise), though their French maintains features that are archaic in France.
Liege, where les Liegeois universally claim they speak the best French.
The Loire Valley, where la Touraine is supposedly the best dialect of the bunch.
Moi? J'sais pas...(Me? Dunno...)
...laura