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Mars Failures: Bad luck or Bad Programs?
HobbySpacer writes "One European mission is on its way to Mars and two US landers will soon launch. They face tough odds for success. Of 34 Mars missions since the start of the space age, 20 have failed. This article looks at why Mars is so hard. It reports, for example, that a former manager on the Mars Pathfinder project believes that "Software is the number one problem". He says that since the mid-70s "software hasnâ(TM)t gone anywhere. There isnâ(TM)t a project that gets their software done."" Or maybe it has to do with being an incredible distance, on an inhumane climate. Either or.
You know, 1/10th of something rather than 1/4. Damn engineers can't figure out the conversion between metric and standard!
Fundamentalism stops a thinking mind.
Before complaining at the lack of manned missions to mars any time soon.
SPAM
I think it's hard to get to Mars because it's far away and it it's in SPACE! It doesn't take a rocket scientist to figure that out! Well on second though....
I'm fairly certian it's sabatoge on the part of the Martians.
Erik
YOU ARE SAYING IMPUDENCE TO ME! THAT IS IMPUDENCE!
because software is one of the only things that could and should be theoretically perfect
maths (especially that based on 1 or 0 is either right or wrong it seems to be only when humans get involved that things go wrong and mistakes happen
I really hope this explains why there isn't a manned mission. =)
My life in the land of the rising sun.
That explains why it's so hard? :-)
If you keep throwing chairs, one day you'll break windows....
I am with NASA on this one (almost always a good idea to stick with NASA). From when I remember of fubar'd mars missions, its been screw ups by the programers.
Just as in the NFL when a receiver drops an easy pass and someone yells that he gets paid to catch passes like that, programers get PAID not to fuck things up.
The ultimate network admin tool needs HELP!
The motivation for achieving Mars is much less than the moon. The reason for this is because there was extreme speculation that the Moon was made of green cheese. Mars is already assumed to have red dust on it. For a society that gorges itself on Big Macs and Cheese Fries this is hardly a worthwhile goal. And as a programmer myself I understand the need to work on projects that will benefit the community as a whole, not on one that will invade a dirt planet.
___ Shout Central - Crushes your nuts!
...is "garbage in, garbage out" right? One of the mottos anyway.
If you underestimate the resources you need to do software right, of course you'll have problems -- either getting it done on time, or getting the quality to the level it needs to be (or both).
That problem is hardly unique to the space programs. And of course, it would be a little tricky trying to upload a software patch to a hunk of solar-powered metal a few million miles away.
I wonder how much NASA et al. really tap the resources they should be tapping -- I mean, there ARE areas of industry where mission-critical or life-critical software has been developed and deployed for some time now. Maybe it's just a question of getting the right kind of experience in-house...
Xentax
You shouldn't verb words.
... on the last two trips to Mars that failed. Communication and incompetence on Earth were the problem. Exactly how do scientists screw up and get the unit system wrong?
âoeThe limiting factor in Mars sample return is mass,â he said. âoeDirect return [of samples] from Mars right now exceeds the cost envelope and performance envelope of the available launch vehicles and upper stages.â
The first samples returned should have mystical properties ascribed to them and then sold on EBay. This should generate enough revenue to substantially increase the size of the "cost envelope"...
cheers
(I got engaged last night) =)
Make it simple. The original software used (like in the moonshots) was Very simple control loops... no OS, no overhead.. just a simple program doing a VERY simple job over and over. Read stick, fire retros as appropriate.
Also, solid state, however big and bulky, isn't susceptible to the radiation that many mega-tiny chips are... by writing (and testing) the software in the simplest manner, and building a VERY specific piece of hardware out of solid state components.. and lots of unit testing... you're more likely to get there.
For the same reason the 486 was the only space-rated intel processor for quite a long time (not sure if thats still true).
I'd rather go on "slower" simpler hardware that does a very specific job... and you can repair with a soldering iron.
meh
What we need is a bit of competition between nations. Let's face it, without Kennedy wanting to 'beat the Russians' to the moon, there would have been no Apollo programme. Nowadays we throw unmanned stuff around and expect it to perform flawlessly with (comparatively) little monetary backing and none of the incentives of older space programmes.
However just throwing money at the problem isn't going to solve it, I'd suggest throwing away the rulebook and starting over for unmanned systems, better craft, less of the multimillion dollar single units and more cheaper devices that can carry out multiple landings at once.
For once, it might be worth imagining a Beowolf cluster of those things - because with many cheaper devices, the mission would most likely have a modicum of success.
It's interesting that he blames the problems of software on external pressures such as management hassling of coders but there is no mention of project delivery methodology. I would be interested to know what methods they uses. Are they using continuous intergration techniques, unit testing, agile methodolgies, XP? These things in my experience are crucial to low bug software. Also who are they employing to write their software? Rocket scientists or coders. In my experience domain expertise counts for very little when it comes to writting rock solid code.
----
Of course, the stupid metric conversion problem only accounted for one of the failures, but it's indicitive of a larger problem. There's obviously a shortcoming in quality control and verification if such an obvious mistake could be overlooked. What less obvious problems are we missing all together? Most of the failures occured during the orbital entry phase, during which time they shut off the transmitter, and therefore don't have up to the second data on the reason for the failure. Sure, they likely wouldn't have much of an opportunity to save the mission, but they would have a good chance at figuring out what the problem actually was so it could be fixed the next time around. Instead, we're left to guess. Cost concerns are always mentioned as the reason, but how much have we "saved" really? An extra million $$ to keep the transmitter on would probably have paid for itself a long time ago.
-Restil
Play with my webcams and lights here
It looks as if the testing and debugging starts at the begining and works through the mission. I suppose this will eventially work, but it seems to be an expensive way to do it.
1st page
Why is Mars so hard?
by Jeff Foust
Monday, June 2, 2003
This June will see the beginning of the most ambitious exploration of the Red Planet in a quarter-century. If all goes well, three launch vehiclesâ"one Soyuz and two Deltaâ"will lift off this month, placing four spacecraft on trajectories that will bring them to Mars by this December and January. Those spacecraft include the first European Mars orbiter, Mars Express; Beagle 2, the British lander built with a mix of public and private funding; and NASAâ(TM)s twin Mars Exploration Rovers, perhaps the most advanced Mars spacecraft even built. They will be joined at Mars by Nozomi, a Japanese-built Mars mission launched in 1998 and forced to take the long road to Mars because of thruster problems.
This should be an exciting time for those interested in Mars exploration, and for scientists and activists alike, it is. If these missions are successful, they should offer new insights about what happened to the planetâ(TM)s water and the potential for past or even present life there: some of the most important questions in planetary science and astrobiology today.
The catch is, if these missions are successful. The history of robotic exploration of Mars, stretching back more than four decades, is littered with failed missions and dashed hopes. Some of these failures can be chalked up to the growing pains of early planetary exploration, when a wide variety of spacecraft of all types failed. Others, particularly the 1999 failures of NASAâ(TM)s Mars Climate Orbiter (MCO) and Mars Polar Lander (MPL), are more indicative of management, programmatic, and other problems, rather than purely technical issues. Understanding these problems, and acting to correct them, are critical if current and future missions are to succeed in studying the Red Planet.
The star-crossed history of Martian exploration
Mars has been one of the most popular destinations for missions beyond the Earth. Since 1960 the United States and the former Soviet Union have launched 34 missions to Mars: 15 by the US and 19 by Russia and the former USSR. NASAâ(TM)s success rate is not too bad: nine of those 15 missions, including the Mars Global Surveyor and 2001 Mars Odyssey missions still in progress, can be considered successes. Russiaâ(TM)s luck has not been nearly as good: 14 of its 19 missions failed, and only oneâ"Zond 3â"can be considered a complete success; the remaining four are, at best, partial successes. Overall 20 of the 34 American and Russian Mars missions, or 59 percent, failed.
Four of the seven NASA Mars missions since Vikingâ"Mars Observer, MCO, MPL, and Deep Space 2â"have failed.
Digging into those statistics in greater detail shows some interestingâ"and troublingâ"trends. Many of the failed missions, particularly those launched in the 1960s, were lost because of launch vehicle failures, not because of any fault with the spacecraft itself. Many Russian spacecraft, from the earliest âoeMarsnikâ missions of 1960 to Mars 96, either failed to leave a parking orbit around the Earth or never made it into Earth orbit into the first place. However, in the last 30 years only one mission out of 16 attemptedâ"Mars 96â"was lost due to a launch vehicle malfunction. This can be most likely attributed to the maturity of launch vehicle development, including the use today of vehicles whose designs date back literally decades.
The problem with Mars exploration now appears to be with spacecraft themselves. Four of the seven NASA Mars missions flown since the twin Viking missionsâ"Mars Observer, MCO, MPL, and Deep Space 2â"have failed, all due to spacecraft problems of one manner or another. (MCO is a borderline case, since there was no technical problem with the spacecraft itself, but rather with how ground controllers operated it.) The only other NASA Mars missions to fail, Mariner 3 in 1964 and Mariner 8 in 1971, were each lost due to launch veh
Well, there are a lot of reasons thing go wrong. Landing a spacecraft on a different planet is inherently difficult, and when you read about how MER-1 and MER-2 will land, it's amazing that they can work at all.
The flip side is that. After Mars Ovserver spectatularly failed in 1993 ("Martians"), NASA started to go with faster, cheaper, better. The idea was, instead of a single $1 billion mission every 5 years with with 90% chance of success, why not 2 $200 million missions every two years, with an 80% chance of success. Everyone loves this idea when it works (Pathfinder), but when a cheap spacecraft fails, the public doesn't care if it cost $10 million or $10 billion, all we know is that NASA is wasting money.
So, the answer is, NASA has hit some bad luck. But the idea of faster, cheaper, better is ultimately a cost-effective one, so if we can solve these software problems (I mean, can't someone independently design a landing simulator?), and NASA can get 80-90%, we'll be getting a lot more science for the dollar. But NASA-haters will always have some missions to point to as a "waste" of money, and try to cut funding as it's mismanaged; other space junkies will insst that anything under 100% is unacceptble, and costs should double to move from 80% to 100%. I don't which attitude is more damaging.
NASA has a "good" track record since Observer, unfortunately, the highest profile missions have generally failed. If MER-1, and MER-2 are both succesful, and SIRTF flies this summer, then everyone should get off of NASA unmanned program's back for a while.
Seriously. Space is tough, as the US has experienced with both Challenger and Columbia, and those should only reach orbit. Going even further away in space is tougher. So much can go wrong, and so little can be done to correct it. Certainly a few blunders like the feet-to-meter bug is huge, but they try. I'm not so sure any private corporation that had been asked to do the same would fare any better. They are pushing limits, where you fail and (hopefully) learn from your mistakes.
Which is why we should continue to try. Giving up, saying "space travel is just too costly and risky" is a big cop-out. If we could send people to a different stellar object (the moon) in 1969 with the equivalent of a pocket calculator but not now, what does that say of our technology? Or sociology? Sure you could take the narrow-minded approach and say "and what does that bring us? The ability to jump from rock to rock in our solar system?" If so, you might as well ask why people decided to go to the poles (just ice) or whatever. You're still missing the point.
Kjella
Live today, because you never know what tomorrow brings
In my years at NASA Goddard I saw a dysfunctional management operate in ignorance of reality.
There was much praise of the employee who "went the extra mile", "put in long hours" and "served the customer" (that applied to contractor employees). There was also very little thought paid to the consequences of those practices.
What's the first thing to go when you're tired? It's not your body -- it's your mind. That's right -- if you're staying at work until you're feeling tired, you're making mistakes that need to be corrected later. The tireder you are, the more mistakes. The tireder you are, the less you can actually do.
I witnessed people who wore their exhaustion as a badge of honor. And, when they got into management, insist that others emulate their bad example. The result that I saw was people who should have been kept out of management becoming increasingly dominant. This was accentuated by the "faster, better, cheaper" ideology promulgated by former NASA administrator Goldin. This ideology was used to get rid of more experienced (and thus costly) people who were aware of the consequences of trying to squeeze more work out of fewer people.
It could take a long time for NASA to recover from this culture. The failure of projects in the past few years, the crash of Columbia could be turning points -- or they could be used by incompetents to justify even more dysfunctional behavior.
"Beer is proof God loves us and wants us to be happy." -- B. Franklin
Perhaps one of the reasons that the software isn't getting done on time is that much of the system is written from the ground up. Perhaps it would be better to design a common, open source spacecraft platform. So many of the basic tasks that spacecraft software must perform are essentially identical. The main differences for critical spacecraft systems would be the hardware. If a general purpose OS and spacecraft toolkit were designed, then the main things that would have to written from scratch for different missions would be drivers for the hardware and various configuration settings.
I'm not sure how suitable RT Linux would be from a technical/performance standpoint, but having a highly portable open source OS would give a flexibility and availablility that would make adoption much easier.
Theoretically, all programs have latent bugs, unless they are too simple to do much.
I've seen the code for some MAJOR blue chip companies and I really do wonder how these people stay in business with the rubbish that they put out. For example some of code drops from our clients don't even compile! The reason for all the crap is that it's very easy to cut corners without it being very obvious immediately. Typically, the first thing that gets stopped when things ar getting tight (either time or money) is documentation, quickly followed by testing. Next it's individual features, removed from the requirements 1 by 1.
Since software engineering is still a 'black art' as far as most traditional engineers and project managers are concerned, there isn't the real intuition/understanding of when things are starting to look bad. Without looking at code AND knowing something about it, you won't stand a chance 'intuiting' whether or not things are going well.
Writing software is an expensive business in both time and money. It's also a very young business without the same 'discipline of implementation' as other areas. Until the process matures and people realise that doing it on the cheap gives you cheap software, things aren't going to change and Mars probes are going to continue to produce craters.
Yes, programmers have erred. To err is human, to allow errors to propagate into mission failures is a failure of systems engineering, and I think that is where the real blame lies. A lot of the problem is thatspacecraft systems engineers often have a very amateurish grasp of software, if any at all.
For example, on Mars Climate orbiter, a junior programmer failed to properly understand the requirements. However, systems failed to:
Helium balloons want to be free.
Space Exploration isn't easy.
Look at the Space Shuttle. The space shuttle has never had a catastrophic computer failure-- but every line of code on that truck has survived review by a group of programmers. They've examined it, line by line, multiple times, in order to ensure that it's exactly right, because the cost of failure is 7 astronauts and a multimillion dollar orbiter.
The new Mars programs, however, are part of the streamlined "do it on the cheap" NASA. NASA put the Mars Rover down using mostly off-the-shelf and open-source software and a small amount of home-brew stuff. No matter how good open source software gets, it still hasn't undergone the level of review that the Space Shuttle code has seen. No matter how popular an off-the-shelf package is, it's not cost-effective for the manufacturer to give it that sort of treatment. NASA can't afford to do that level of code review because that costs them the ability to do some other program.
NASA is simply trying to do more with less in the unmanned launches, and the cost of that is we need to expect some failures. These failures are unfortunately very visible...
-JDF
Then after 3 months you are then shot into a planet and stopped by a parachute and then some air bags. The entire time literally thrown into the surface.
And all this with the safety and security, of the lowest bidder.
I dunno, you tell ME why these missions have a high failure rate. Could it be there is no humans on board therefore not as much care is taken to insure the safe delievery of these machines? Could it be the fact that they are designed not to go to mars, but to go to mars as cheaply as possible. Could it be that no one really has a whole lot of information so a lot about mars is (pun intended) hit or miss?
Ignore the "p2p is theft" trolls, they're just uninformed
Part of it was the fact they had absolute geniouses working on the problem. Think of it, they designed a system in the late 1970's, tested it on the ground, and had it successfully fly for 20 years without a major "oopsie". Or rather, if a major "Oopsie" happened, they had ways around, over, or through it. They spent YEARS developing the flight software for the Shuttle.
Software CAN be done right. It just has to be a priority.
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
I have to really disagree with this. NASA is used to dealing with alien climates and terrain and astronomical distances. NASA is also used to dealing with problems. They have some of the best problem solvers out there, and when something goes wrong, then tend to pinpoint why. When NASA says A, B, and C are the causes of failure, I believe them. When NASA cannot figure out why something went wrong, I worry.
What I'm trying to say is, distance and inhuman conditions shouldn't have that much of an affect on how well a probe works. We built Voyagers I and II, didn't we? They worked even better than expected. And they encountered climates and conditions which make Mars look easy.
NASA has dealt with so many varying circumstances and climates over the years, and been so blunt about their mistakes, I find it hard to believe that they would blame the failures of an entire class of missions on something "easy." And yes, blaiming failures on software is an easy way out, how many times have you heard someone say "Oh! It must be the software!" when something doesn't go as expected?
Now, I know this guy doesn't speak for NASA as a whole, but as a NASA trained administrator, and the head of some very large projects, I'm willing to take his opinions at face value. If he says it looks like software has really been a cause of failure, who am I to laugh at his expertise and belittle his explanations? I might not like his explanation, but I buy it.
---
"Of course, that's just my opinion. I could be wrong." --Dennis Miller
Never test for an error condition you don't know how to handle. -- Steinbach
~Idarubicin
Most PHB's haven't figured it out yet: SOFTWARE IS HARD. It's amazingly complicated. It's also notoriously hard to come up with realistic estimates.
PHB's also haven't figured out that developers aren't interchangeable widgets. If you know C, it doesn't mean you'll be immediately productive in Korn shell scripting, and vice-versa.
PHB's also haven't figured out that experience is key. There are exceptions, but generally speaking, a young hotshot isn't going to be as productive as an experienced professional. Sure, the young hotshot might get v1.0 done first, but it'll be buggy, unreliable, unscalable, hard to maintain, etc.
The "problem with software" is almost entirely a management issue, imho.
-Teckla
We haven't seen software failures taking out manned missions, two shuttles failed from the high stresses of takeoff and re-entry. Just a guess, but the engineering standards are probably much higher for the manned programs, and more people review the code. Also, keep in mind that NASA has been experimenting with the idea of saving money with faster paced development which means some reduction in review and other QA standards, particularly on unmanned planetary missions. It may even be that this method is cost effective in spite of some high profile failures.
But it's gotten much prettier!
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
According to this page only 3 of 26 missions to Venus have been total failures. When you consider that Venus is a much more hostile environment than Mars then you have to conclude that either Mars is just plain unlucky or mission planners are getting something wrong.
-- "Sponges grow in the ocean. I wonder how much deeper the ocean would be if that didn't happen."
However much you may disagree, simple Newtonian dynamics and is all it takes to get a space probe from A to B in the vast majority of cases. It's a well-understood problem domain.
Dragging in stuff like chaotic long-term behavior of n-body systems, while an interesting fact in itself and worthy of study, has very little to do with the engineering problem at hand. Ephemerides for all major bodies in the solar system for the coming hundreds of years are known up to uncanny accuracies (metres) and plotting the trajectory of a probe is simply a matter of numerical integration, to put it bluntly.
Now when someone mixes up metres and feet things go awry. But don't claim stuff like this could have been prevented by hiring more mathematicians. It's simply a case of human error, something that happens in the Real World.
Having a high IQ, my friend, is no excuse for making stupid claims about things you don't know anything about.
I think the primary problem is that the technology to build and design probes changes too quickly, and affects design.
I always thought that there should be a way, to build a probes navigation and propulsion systems in a standardized whay so that avionics software wouldn't need to change that much.
Sort of a standardized platform if you will for doing solar system exploration.
This platform would consist of a number of parts that would not change, and could be reusable in a number of different configurations for building a probe, depending on what its job was.
Cameras, photometers, spectrometers, and power sources could all be packaged in the same why depending on the probes job.
Every probe that nasa launches is always customized and built around cost and included packages.
I am not so sure that is the best way to go about it as you have to reinvent all the software to manage the probe every time you build one.
Probes should be cheap, produced in high volume, (thousands) and interchangeable.
With a standardized approach, failure rates should come down a bit and costs should be reduced.
-Hack
Got Geometrodynamics? Awe, too hard to figure out? Too bad.
Heh, I was a part of a space failure myself. We were using pretty much off-the-shelf equipment, but it passed NASA spec shake and thermal testing. What probably did it in was radiation...in low earth orbit we figured there wouldn't be much risk of radiation problems.
If we were to do it again, we probably would have had some kind of radiation-resistant reset system, because building the whole thing in rad-hard would be very expensive (our budget was $1500 plus donated equipment!) But having a few rad-hard devices to reset the box in case of a crash would probably have been affordable.
About 100 amateur radio operators contacted our payload, and relayed their GPS coordinates to others using amateur packet radio. At the same time, the GPS unit on board the Spartan satellite transmitted its position to listeners on the ground as well. But had it not crashed after about 17 hours, it is possible that several hundred other amateur radio operators would have used it.
Venus, like the woman she is, is a real bitch and a half.
Thick sulfuric acid atmosphere?
Gigantic storms?
Temperatures that will melt aluminium?
Ahh, I need to stop. I'm getting flashbacks of my ex-gf.
and the Viking landed. Dad points out that the budget for the Viking was in the neighborhood of 1 billion dollars, and that was when a Mustang Mach 1 cost just over 4 grand. The space program doesn't have the money now to do the missions the right way, which is unfortunate... the developments of NASA when they had tons of money were numerous and wonderful (i.e. Tang!)
stuff |
Before we continue to crucify programmers, we need to remember how hard it is to really get to Mars, from a purely spacefaring perspective.
From my experiences flying to Mars in Orbiter space flight simulator (FREE!), several problems become apparent:
Mars is a fantastically difficult target to reach for two main reasons. It has very little gravity, and very little atmosphere.
If you shoot for something big, like Jupiter, you find that it is hard not to miss it. It's gravity well is so massive that navigational errors en route are relatively insignificant. Mars doesn't help you very much in this regard. An Earth to Mars flight has to be dead on.
When you get there, you are likely going to want to use the atmosphere to do at least part of the braking maneuver to get into Mars orbit (as most modern probes do). The problem is that Mars has a very thin atmosphere. Think about the sheet of paper analogies with Earth re-entry. Earth's atmosphere goes MUCH farther into space than does Mars'. You have to get dangerously close to the surface (within 50 miles) to effectively aerobrake using Mars' atmosphere. So with Mars, you are more talking about a near-ephemeral gossamer thin 1 cell thick membrane you have to hit the edge of rather than a nice, thick piece of paper.
... and the Mars vehicles. The Shuttle carries people. You can afford to cut corners a little if no one's going to get killed.
Sean
We like to prey on these simple glitches only because it is poetic to do so. Saying the MPL failed because a programmer failed to initialize a variable sounds much more interesting and is much easier for a reporter to remember than saying MPL failed because a programmer failed to initialize a variable, which determined how close to the planet the retro-rockets would turn off, and that this was observed in the testing laboratory, but the test data was not annalyzed until after the crash.
0xfeedface
Take their early record, before Mars 1 got to Mars, they had had a series of attempts. Two, known to the West as Mars1960 A and B reached Earth orbit then disintegrated.
Mars1962 A exploded in orbit at the height of the Cuban Missile Crisis - briefly causing a panic with the Americans thinking a missile attack was underway. Fortunately the computers soon told them that doomsday had been averted.
Next, was a partial success - Mars 1. Which smashed the record for deep-space communications with Earth across a distance of 106 million kilometres. Unfortunately it failed just before reaching Mars.
Mars1962 B exploded in Earth orbit and didn't appear in the Soviet record.
November 1964 saw the launch of Zond 2, a highly advanced probe using ion thrusters to perform stabilisation and orientation tasks. It may have also been the first probe to carry a lander. It died a long and lingering death before sweeping past Mars at only 1400 km altitude. (By this time the US had got their first Mars probe to the planet in working order, Mariner 4 took 22 pictures of the planet from 10 000 km. (Its sister ship, Mariner 3 had failed en-route)).
Neither side went to Mars in the next launch window, but 1969 was a busy year. Three attempts for the Soviet Union, including at least one lander. Mars 1969A exploded in flight as did Mars 1969B. Mars 1969C was removed from the pad after cracks developed in the relatively new Proton rocket design. (Cracking in the Proton was also a major reason for the failure of the Soviet Union to send a manned mission around the Moon during 1969). The US had a twin success with Mariners 5 and 6 flying past Mars.
On to 1971 and a pair of launches for the US, Mariner 8 ended up in the Atlantic, Mariner 9 went on to become one of the most successful missions ever and the first probe to orbit Mars. For the Soviets - mixed results again. Their first mission reached Earth orbit, but went no further and was named Kosmos 419. But then both Mars 2 and 3 left Earth orbit. They each comprised of a lander and an orbiter. The two craft jettisoned the lander before entering Martian orbit - just as the planet entered an intense dust storm with raging winds and almost total blackout.
Mars 2's lander was apparently DOA, it remained silent and does not appear to have returned any data. It was however the first craft to hit (not land on) Mars. Mars 3's lander was more successful. It entered the atmosphere, deployed parachutes and landed on rockets. It deployed its antenna and began to transmit the first picture from the Martian surface. Sadly, just 20 seconds later the transmission stopped. The Soviets said that the lander's parachutes had been caught by the storm and pulled it over.
Mars 2 and Mars 3 orbiters remained on-line and performed experiments on the Martian atmosphere and took photos of the surface. So I would call both missions a partial success and Mars 3 almost a triumph.
The next window was 1973 and the Soviets planned no less than 4 missions to Mars. Mars 4 and Mars 5 would be orbital missions, studying the planet much like Mariner 9, but also serving as telecoms relays for the Mars 6 and Mars 7 heavy landers.
Incredibly, bearing in mind the past track record of the Soviets, all four missions reached Mars in working order. Then everything went wrong. Mars 4's main engine failed and the probe did not enter orbit, it relayed images of the planet as it swept past into solar orbit. Mars 5 was next and was the only unqualified success of the year; it was the first craft to return colour images of Mars.
The two landers then arrived, Mars 7 first, it deployed the lander, but an attitude problem meant that the lander actually missed the planet entirely! Mars 6 was more lucky, the probe entered the Martian atmosphere, took readings all the way down and went dead ab
But in the article:
That was just too perfect.
This is my sig. There are many like it but this one is... Oops. Frank, I've got your sig again! Where's mine?
Just look at the rate of failure for early moon missions
It's a hard probelm to send a probe to the Moon or Mars. landing and aerocapture at Mars are dicy things.
There are 10 types of people in this world, those who can count in binary and those who can't.
Here's the problem as I see it: As software and hardware have become more complicated, there's a need to increase testing. Instead, in order to meet NASA's new budgetary requirements, funding in general, and specifically for testing, has gone down. So, it's not possible to completely test all of the hardware AND software, as it should be.
As an analogy: If we were talking about commercial airliners; these probes would never be certified to fly.
I'm not putting all the blame on NASA here; although, it is apparent to me that they need to start reporting what it's actually going to cost. Having said that, Congress is equally complicit; they need to come to the realization that it's expensive to do work outside the atmosphere (they apparently don't understand this...)
Software can be done right. Anyone who doesn't believe this either (a) does not know how many millions of lines of software are involved in avionics and air traffic control, (b) never flies on an airplane, or (c) has a death wish. Of course I guess there's also a fourth possibility - when all else fails, blame the software. The space shuttle's record proves that software can be dependable, but also illustrates that making it that way is very, very expensive. Just a matter of priorities.
I think one of the factors contributing to the poor Mars success rate is orbital mechanics. The launch window to Mars opens for only a month or so every two years. This is the longest interval between window openings for launches from Earth to any other planet; windows to the other planets open at roughly yearly intervals or less. Since missing the launch window means waiting another two years, this undoubtedly creates enormous schedule pressures on any team preparing a spacecraft for launch to Mars.
Your comment about manned vs unmanned makes absolutely no sense. One could buy a hundred or a thousand unmanned planetary missions for what a single manned mission would cost, and there would still be no guarantee that the manned mission would succeed. Yet we could easily afford to have many of those unmanned missions fail.
I say that the manned space program is one of the major contributing factors to the poor Mars success rate. More specifically, the enormous sums of money that the Shuttle and ISS have siphoned from the far more productive unmanned planetary program and flushed down the drain.
Unfortunately, that page is incomplete and misleading, as it only mentions the probes that actually got near Venus. For example, the page lists Mariner 2, but not Mariner 1. Mariner 1 went off course due to a sofware error resulting from a missing hyphen. Venera 1, though in the list, suffered a communications failure and was a complete failure. Also failing was Sputnik 7, whose 4th stage didn't ignite. Sputnik 23 and 24 never made it from Earth orbit. Sputnik 25's 3rd stage blew up the entire craft. Cosmos 21 failed to leave Earth orbit. Venera 1964A and Venera 1964B failed to achieve Earth orbit. Venera 1964C did, but couldn't leave orbit (renamed Cosmos 27. Soviets apparently named things in Earth orbit as 'Cosmos', even if they were failed missions to somewhere else). Zond 1 is on the list as being succesful, but contact was lost with it 2 months before it got to Venus. Also failing: Cosmos 96, Venera 1965A, Cosmos 167, Cosmos 359, Cosmos 482. Obviously there have been far more failed missions to Venus than your list implies.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
(1) Schedule realistically, so that tasks can be completed without overtime. This may mean some things just cannot be done in the desired time period. Learn to accept that.
(2) Hire and retain sufficient staff, so that the work can be shared between multiple people. This may mean that some of the time the company will be overstaffed. Accept that too.
Obviously both these suggestions come with a pricetag, but lost missions aren't free either...
A quote from a recent Newspaper article:Language is important. The numbers say it, the metrics say it, the successful projects say it, even some
The rest of us will just have to settle for actually doing this work, satellites, laser eye surgery systems, aircraft, subs etc instead of making yet another kludgy VB system to sell the latest in sportswear or whatever.
Zoe Brain - Rocket Scientist