Mars 3 (Various Topics Merged) |
Mars 3 (Various Topics Merged) |
Dec 29 2004, 10:36 PM
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Interplanetary Dumpster Diver Group: Admin Posts: 4404 Joined: 17-February 04 From: Powell, TN Member No.: 33 |
On my website sometime back, I added a page on the image fragment sent back by the Mars-3 Lander. I released serveral versions, including the best quality processing using othodox techniques I would use on other images plus colorization here:
http://pages.preferred.com/%7Etedstryk/fragmentc.jpg However, I released another image, which I called a "What if" image. This image can be seen here http://pages.preferred.com/%7Etedstryk/m3s5b.jpg It was produced via extreme processing of the original data to make a Mars-like scene, but I made it clear on my website it was only a speculative image. I strongly doubt if the raw data even shows Mars at all - it could be all noise. But since this mode of processing looked strangely Viking-like, I figured I would put it on the web. I was warned by several, who said that while fun, some kooks might take it seriously. My response was that I really don't care what kooks think. Then I noticed this web page: http://en.wikipedia.org/wiki/Mars_2 They used the overprocessed image. I feel like it is being presented as a true photograph. This is of concern. -------------------- |
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Guest_BruceMoomaw_* |
Apr 18 2006, 10:18 PM
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Guests |
The Soviets actually do firmly know why Mars 2 failed, as V.G. Perminov said in his interesting historical document "The Difficult Road to Mars". They didn't trust the accuracy of their radio tracking network, so they incorporated an optical guidance system into the Mars 2 and 3 orbiters to allow them to calculate the optimal course for their final pre-arrival midcourse correction. Unfortunately, the Soviets had slightly inaccurate data on Mars' ephermeris, and so -- while Mars 2's onboard system worked as planned -- it ended up putting its lander onto a course directed at too steep an entry angle, which would have led to the lander crashing in any case before its parachute could properly brake it.
The Bad Luck Fairy that has always haunted the Russian Mars program struck in a particularly brutal way that time. First, the next year the US (as part of a planetary science data exchange program) provided the Soviets with a corrected Martian ephemeris -- and, second, it turned out afterwards that if the onboard optical system HADN'T made that correction, Mars 2's preexisting approach trajectory would, by pure luck, have put the lander on a properly shallow entry! The failures of the Mars 3 and 6 landers remain more mysterious. Perminov expresses his suspicion that Mars 3 might perhaps have been knocked out by an electrostatic discharge from the giant dust storm it landed in. As for Mars 6, it failed at about the time its final solid-fueled braking rocket was supposed to fire -- meaning that the rocket could have fired at an inappropriate time due to Martian conditions, failed to fire at all, or exploded. |
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Apr 18 2006, 10:41 PM
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Interplanetary Dumpster Diver Group: Admin Posts: 4404 Joined: 17-February 04 From: Powell, TN Member No.: 33 |
As for Mars 6, it failed at about the time its final solid-fueled braking rocket was supposed to fire -- meaning that the rocket could have fired at an inappropriate time due to Martian conditions, failed to fire at all, or exploded. It is thought that it probably fired too late...in other words, it was too close to the surface when it fired, so it was still going too fast when it hit. It is because the timing was a bit off. Still, the fact that the timing was as close as it was is remarkable, given that, due to computer problems, Mars-6 had been unable to receive ground commands for five or six months at this point! It was purely operating on pre-programed sequences. In fact, the Russians were expecting this, although they were hoping for a stroke of luck, because they realized, as it approached and the trajectory was refined, that this was a problem, but, since Mars-6 couldn't be commanded, they were helpless to do anything about it. However, the failure of Mars 4/5/6/7 was really not bad luck. It was bad microchips (which is what made Mars 6 uncontrollable, Mars 7 miss the planet, Mars 5 depressurize, and Mars 4 unable to fire its breaking motors). The scientists and engineers knew it and wanted to delay the mission until the next window to replace them, but since there was a chance that, as Mars-6 came very close to doing, they still might last just long enough to arrive and touch down for a brief surface mission to get the "first," the political powers ordered them to proceed with launch. They were going to try again in 1975 with a similar lander with good microchips, which may well have suceeded, but since Viking was much more capable (although it would have had some experiments that Viking didn't), and the Soviets had already made it to Venus, once it was clear that Viking would launch in the 1975 window, they mission was cancelled. Had Viking been delayed, it would have launched. -------------------- |
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