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Galileo, Consumed by Jupiter
We ran stories about Galileo's impending incineration earlier this month and last November when the plan was decided.
Here is a typical passage from Journey Beyond Selene, about the worst glitch in Galileo's mission, and the beginnings of how it would be worked around. Failures and the engineers who salvage them are the recurring tragic, triumphant story of our missions into space. Reproduced without permission:
With such triply redundant hardware built into their spacecraft, mission planners could feel confident that they had designed a communications system that was almost completely resistant to failure, and for the first eighteen months after Galileo's 1989 launch, there was no reason to assume anything would fail. Finally, on April 11, 1991, when the ship's trajectory had spiraled out as far as the edge of the asteroid belt between Mars and Jupiter, JPL planners decided it was at last probably safe to unlock the high-gain antenna and spread its ribs. It was only then that they'd learn if triply redundant was redundant enough.
Though the deployment of the high-gain system was not a complicated exercise, it was a critical one, and for that reason the chieftans of the Galileo project made sure they were there to watch it happen. On hand at the flight director's console that afternoon were mission director Neal Ausman, deputy mission director Matt Landanow, and project manager Bill O'Neil. O'Neil and Ausman were far and away the higher ranking of the three men, but Landanow, they all knew, was far and away the most knowledgeable. As chief engineer during the Galileo design phase, he had familiarized himself with every strut, nut and rivet of the ship, and could practically describe their placement and purpose from memory alone. If anything went wrong this afternoon, Landanow would likely be the first person to recognize it -- and the first person to come up with a way to fix it.
For the first forty minutes or so after the deployment command went up, O'Neil, Ausman and Landanow had little to do. Like so many other JPL controllers before them, they knew they would have to tolerate the nonnegotiable limits of light speed, waiting twenty minutes as their signal traveled from Pasadena to the spacecraft and then another twenty minutes as it traveled back again. For that entire time their screens told them nothing, flickering merely with the self-evident information that their command had indeed been sent. Finally, after just over the anticipated forty minutes had elapsed, a column of numbers began to blink on the glass. Landanow gave the figures a quick scan and immediately noticed something amiss. He read them again -- a bit more closely -- and this time started to feel downright queasy. The antenna, from all indications, was pulling what the engineers called stall current. The motor was drawing power, the deployment gears were engaged, but the ribs of the umbrella appeared to be going nowhere at all.
"We're stuck," Landanow said flatly.
"How can you tell?" O'Neil asked.
"The current is saturated, something is jammed," Landanow said. "In any event, the antenna's not budging."
Ausman gave the numbers on the screen a read of his own, confirmed what Landanow was saying, and immediately called out to his flight controllers, instructing them to send a second deployment command up to the ship. The engineers complied, and forty minutes later another stall signal came down. A third command yielded a third signal, and a fourth a fourth. With each new report Landanow winced. If he knew this ship -- and he surely did -- he could all but guarantee that whatever was hanging up the antenna was not much: a single too-tight fitting, perhaps, a single protruding bolt, one that was situated in just such a way that it managed to jam all eighteen ribs. If it were somehow possible to transport the Galileo spacecraft to a hangar in Pasadena, Landanow knew he could probably roll over a stepladder, climb up to the antenna, and spring it free with his hands alone. But Galileo was not in a hangar in Pasadena; it was tens of millions of miles away, at the edge of the asteroid belt between Mars and Jupiter, and more elaborate measures would be necessary.
Galileo, Consumed by Jupiter
Conceived in 1977, launched in 1989, the spacecraft Galileo ends its 34th orbit exactly one hour from now
Little early for the past tense 'consumed' don't you think?
(I can already see the 'not any more' post below this one in an hour)
I was reading this article earlier and I was thinking what a sickening feeling it must have been when they realised that the main antennae was not going to deploy properly leaving them up the creek so to speak. I think its a brilliant achievent that they managed to recover from this huge setback, reprogram the vehicle, retask the mission to focus on the Jovian moons and still get so much useful information. A very cool piece of engineering improvisation.
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
that show that "faster, better, cheaper" shouldn't mean cutting as many corners as possible while earthside. Galileo was probably one of the top few probes ever on a measure of information learned per dollar spent NOT because we saved money while building it, but because it was built so well that it just kept on transmitting when by all rights it should have gone quiet a long time ago.
Well, good thing the didn't try to land it on Pluto and set the whole planet on fire. You might want to take some nuclear physics at some point as well, it is quite enlightening to learn what being nuclear really means. Hint: It doesn't involve the magical ability to blow up everything it touches.
I read the internet for the articles.
Heh, historically jupiter has been hit by rocky objects that could have been mistaken for planets. The article you link to is awful, and should be modded as funny. Particularly the first sentence of the conclusion, "Let's all keep in mind that NASA has lost two shuttle crews because of its own internal political problems." It is pretty pathetic that the best they can come up with is this.
-Sean
Briefly, it's because it might otherwise crash into Europe (the moon, not the continent). It has itself discovered that conditions (water) exists on Europe that might habour life (however primitive), and crashing a sattelite from Earth with possible bacteria might contaminate Europe (the moon) with lethal bacteria.
It might sound like far-fetched science fiction - it ain't. It's the official reason for the Jupiter crash.
I'm in a Unix state of mind.
Metis [MEE-tis] is the innermost known satellite of Jupiter. According to this page Metis orbits at a mean distance of 127,969 km with a Mean orbital velocity of 31.57 km/sec. So 48 km/sec is not so ridiculous.
No electrons were harmed creating this post, though some may have been subjected to electrical and/or magnetic fields.
Maybe they should work on getting everyone all home intact rather than in itsy bitsy pieces first. If a piece of friggin' foam no bigger than your head can incinerate a billion dollar Space Plane and they're too st00pid out the gate to realize that, I sure as hell don't want nuclear reactors and ION engines raining down on me.
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