I was recently looking over the list of all unmanned Mars probes, those that failed and those that worked. This is the one that has triggered the much quoted "2/3 of all Mars missions have failed" statistic, had some talk about a Galatic Ghoul out near Mars and led to one of the MER scientists describing Mars as the "Death Planet". However, when you look at the list you notice that Mars is actually only a Death Planet for Soviet/Russian probes, for American probes it's record is actually quite good.

Effectively 100% of Soviet/Russian mars missions have failed. The Soviet Union/Russia has sent the most probes to Mars of any nation (16 vs 14 for the U.S. prior to MER-A and MER-B) and so it's 100% failure rate skews the numbers very badly. The only Russian probes to Mars that were not complete failures were Mars 5 launched in 1973 that failed after a few days in martian orbit and Mars 6 that failed minutes after landing on Mars.

The U.S. record with Mars missions on the other hand has been quite good (much better than the 100% failure rate of their Ranger Lunar probes prior to Ranger 7 for example). Out of 14 U.S. Mars missions since Mariner 3 in 1964 (excluding MER-A and MER-B) they've only had 5 failures. That's a failure rate of a little over 1/3, nowhere close to the oft quoted 2/3 figure that's be given so much publicity recently. What really hurt them in the public eye (and short memory) was losing both MCO in '98 and MPL in '99--these back to back failures made everyone forget the many successes that had preceeded them).

Japan has of course a 100% failure rate too but with only one Mars probe launched that's not very useful statistically and Europe has had either one or two probes depending on how you look at Mars Express vs Beagle 2--1 mission or two, Europe and the UK or both European?

The bottom line is obvious--if you want to go to Mars go with the Americans, then you'll have a 2/3 chance of making it!

N.B. I'm not an American. :-)

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David S.

"Why are the pretty ones always insane?"
-- Chief Clancy Wiggum, The Simpsons.

What's the url for the article you referred to?

Littlemews wants to know what recent technology has enhanced our capability of reaching the red planet successfully. Has there been a greater success rate since the year 2000?

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Climate Change Australia

The list is in Jan 10 edition of New Scientist, dunno if they have it in the online version. There has been no recent enhancement to capability of reaching Mars successfully judging from the list of failed and successful missions. The first U.S. success was Mariner 4 in '64 and their first failure was Mariner 3 also in '64. Mariners 6 & 7 (1969) worked, 8 failed and 9 succeeded (1971).

Since 2000 there's only been Mars Odyssey, Mars Express/Beagle 2 and the two MERs launched (Nozumi was launched in '98) so only one of them can be declared a complete success so far--Odyssey-- though Mars Express and at least MER-A are obviously looking hopeful and Beagle 2 isn't.

Another interesting point is that of the U.S. Mars landers 3/4 have succeeded--Viking 1 & 2 plus Pathfinder--only MPL failed. Hopefully MER-A and B will improve on this excellent record. Who said landing on Mars was hard? ;-)

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David S.

"Why are the pretty ones always insane?"
-- Chief Clancy Wiggum, The Simpsons.

maybe the technology and the calculation of Mars's orbit of 1960 - 1980 is not that good, therefore they fail alot... (LOL where is my first post ><)

thats actually an interesting point, it just occurred to me that maybe we have several orbits and orbital fluctuations actually not accurate enough. Is this at all possible as a scenario and explanation?

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Damien,
International Baccalaureate Physics teacher
Optics, Photogrammetry and Remote Sensing Instrumentation Major
Admin: Pacific Science and Art

It seems unlikely, most of the Russian Mars probes seemed to have failed either near to Earth (usually booster failures of some sort) or enroute to Mars (usually some sort of electronics failure causing loss of radio communication). Some exceptions were Mars 5 (failed after a few days in orbit) & 6 ("lander failed on impact") as well as Mars 7 which is described as "Lander missed the planet"! Mars 2 burned up entering the Martian atmosphere and Mars 3 failed 20 secs after landing on Mars.

The American failures are pretty similar but less frequent--Mariner 3 failed during boost phase when the shround failed to separate from the upper stage, Mariner 8 "failed during launch", Mars Observer launched in 1992 apparently failed as it tried to fire it's main engine to enter orbit around Mars (as I recall they think the engine exploded) and of course the Mars Climate Orbiter failed in '98 due to the infamous metric/imperial units snafu and burned up in the martian atmosphere having stepped on the brakes too hard. Mars Polar Lander is believed to have crashed due to a software fault causing premature shutdown of the retro rockets during final descent phase.

So maybe Mars 7 could be blamed on orbital navigation issues, but apparently none of the others.

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David S.

&quot;Why are the pretty ones always insane?&quot;
-- Chief Clancy Wiggum, The Simpsons.

I don't think there was any problem with the orbital mechanics... after all, someone thought of the Voyager 2 grand tour in the 60's and that's always staggered me how they managed to do that with such precision. Not one planet, but 4!!

Interesting stats though, dshan - I once worked with someone who was a fervent believer of UFO's and was adamant that the reason there was such a high failure rate (in his opinion) was that the probes were being destroyed by - drumroll - forces unknown LOL

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"The stars are my home"
"I've seen things you people wouldn't believe... Attack ships on fire off the shoulder of Orion... I've watched c-beams glitter in the dark, near the Tanhauser Gate... all those moments will be lost, in time... like tears in the rain..."