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NASA Announces De-Orbit Mission For Hubble
maglor_83 writes "NASA has announced the end for Hubble. It plans on performing a "robotic de-orbit mission", and apparently its not due to the monetary costs associated with fixing it, but rather the risks involved. NASA's new goals are now manned missions to the moon, as a platform for Mars."
When do they intend to deorbit Hubble? As I understand it, the first thing expected to die on Hubble are the gyroscopes. One needs three gyros to point the scope at a celestial target. The deorbit module will definitely have its own pointing system (used for docking, among other things). Which means the mere presence of the deorbit module would fix Hubble. So what's their criteria for dropping Hubble into the Pacific?
The moon would be a good place for a prototype space elevator. If it turns out to be a good source for Helium-3, AND we turn out to have a good use for Helium-3, then the moon may be otherwise useful. Mars, on the other hand, offers us the opportunity to do scientific research that simply isn't possible any way other than landing on another planet, and Mars is the most earthlike of planets around (sad as that is) and may have been significantly more earthlike in the past. It's worth going there. As for measurable, immediate scientific benefits, you have to look further than the end of your own nose if you're going to learn anything, and you have to look further than the end of this week if you want to help humanity.
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Mars, on the other hand, offers us the opportunity to do scientific research that simply isn't possible any way other than landing on another planet,
Like what? And what can we not do remotely? Why send astronauts there is what I am asking.
It's worth going there.
What I am saying is not that we should not go to Mars. I am saying that sending people to Mars right now would not have the scientific payoff that other investments in our space program might.
As for measurable, immediate scientific benefits, you have to look further than the end of your own nose if you're going to learn anything,
Yes, and your point is?
and you have to look further than the end of this week if you want to help humanity.
See my above comments on best bang for the buck.
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So, sending a team of astronauts into space just over 600km away, still within the confines of the Van Allen belts, is terribly dangerous, but sending them out a minimum of 55M kilometres is safer?
This sort of mission was almost *routine* three years ago...and now it's "too risky". Those NASA people sure have turned into wusses. >.>
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A better idea would be to build two orbiting radio telescopes in Earth's orbital path, on opposite sides of the sun and with the same orbital velocity as that of Earth. This essentially fixes the Earth and the two telescopes in place relative to each other and keeps line of sight communications between Earth and each of the satellites at all times. Massage the resultant data together via the wonders of very long baseline interferometry and you effectively have an single radio telescope the diameter of Earth's orbit.
UNIX? They're not even circumcised! Savages!
on Hubble there are reaction wheels and magnetic torquers. there are no thrusters. Hubble can manage its orbit with the reaction wheels and magnetic torquers which interact with the Earth's magnetic field. They cannot provide a large amount of force but like pushing a swing, a little push here and a little push there... Maybe use some atmospheric drag here and there... I would think that NASA would try to save money on hardware and try some orbital mechanics to bring it down without developing a "deorbit module" Kinda like Skylab. (ok Skylab had some thrusters, but it also had control moment gyros) I read the referenced article, no mention of a seperate "deorbit module" Some googling pointed to a proposed "deorbit module" that may cost up to $1bn. I think they will look long and hard at orbital mechanics to bring it down without the expense of a "deorbit module" but hey, I don't work for NASA. Hey, let's give lockmart some more tax money. Yes, I should talk to my father more!
Hubble was one of the first casualties of the Challenger explosion. Remember that the first thing that needed to be fixed was a flawed mirror?
While I was in undergrad at UT, I was an officer in the local SEDS chapter, where Dr. Hans Mark explained that the mirror was known to be flawed before it was launched. When the Challenger exploded, NASA shut down everything. Hubble remained, unrepaired, in a dark warehouse somewhere. When they got the HST program back up and running, they'd long forgotten their problem with the mirror.
HST was a great idea, but there were some big screwups attached to it.
If the satellite is smaller, one would attempt to position a satellite to maximize its drag force with magnetic torquers and IRW. It makes it easier, too, if the Sun is active (*). By dragging it, it slows its revolution rate, which leads to decay in orbital altitude. We've downed satellites this way a few times. But the HST is probably too large to do this safely.
CGRO was designed to be de-orbited at its end and had a thruster. I guess NASA really was planning to bring the Hubble down with the Columbia, since it has none of that.
(*) when the Sun is very active, it puffs up the scale height of the atmosphere. In turn it increases the particle density in the low earth orbit, which leads to a greater drag force.
I was chatting with Marvin Minsky a few days ago, we started bitching about space, and he had this sad story to relate:
Once some of the ISS modules were relatively complete and ready for launch, NASA rounded up a group of dignitaries to bless it (I can't think of another reason why they were called in, and you'll see why I had more interesting things to ask about..), and he noticed an engineer really screwing up a docking procedure. He asked why they didn't just have a simple bit of robotics to handle it (any of a billion implementations would work great for something this trivial), and the answer was that NASA had dictated from high up that a human must be the operator for a wide class of tasks.
So there you have it! The space industry has some luddite motivations, which is absolutely terrifying. And unfortunately the great success of JPL/Caltech's probes gives more justification of their _small_ budgets (wow! you're so great you can keep being great with only $10 !!); I guess a large set of the administration still feels a need to justify 'manhood'. fucking retards.
First you're assuming that they actually have the correct engineering drawings. A GAO investigation of ISS revealed that although NASA had a system that was supposed to track the ISS engineering drawings, they didn't actually have the correct drawings.
Secondly, the cost of making a one-off of just about anything goes UP over time, unlike the cost of mass manufacturing items which goes down.
And third, I doubt that they would build another Hubble even if they could. They wouldn't be able to resist making a lot of changes to take advantage of advances in technology, so the design work would all get redone anyhow, resulting in no net savings.
This is trotted out every time that the space program needs justifying and guess what, its bogus. Non stick frying pans were being developed during the Napoleonic wars when the English embargo prevented the French getting their hands on enough cooking grease. Hence LeCreuset.
Guess what -- THAT's bogus.
Great example, by the way. LeCreuset is nonstick cookware, I'll give you that. However, they do not use Teflon for their ceramic cookware. They did not invent Teflon or anything at all similar. They do USE Teflon, however, in their kitchen textiles, as a fabric protector. Because, that's right, teflon is useful for more than non-stick cookware! Hooray!
In fact, Teflon is among the (at the top of the list I believe, but I'm not willing to back that up) most slippery materials known to man. Not simply the cheapest or most widely available, it is extremely unique.
I do agree with you in general that the Hubble has delivered far more science than any manned mission ever has. However, I believe both have their merits, and both deserve funding.
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Karma to burn, so...
Zubrin is a barking mad cult leader labouring under the messianic misapprehension that he and only he can get us to Mars. Anybody who says otherwise is a fool and a communist.
If you read his statements made after the release of the basic outline of the current Bush space plan, he stops just short of calling treasonous any effort to go to the Moon as a first step or staging post rather than directly to Mars. He's not interested in consensus building, just his own (dubiously costed and hand-wavingly engineered) master plan. There are a growing number of people in space advocacy who consider him as mad as a bus. In a field full of dogmatic fantasists, he dwarfs all others for sheer cultish zealotry.
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I really thought we could keep Hubble going until the James Webb Telescope goes up. Guess not. The proposal I just put in last month might be my last chance to do a new Hubble project (failure is expected for 2007, but could be sooner, or a little later). I've got some grant money to hire a postdoc, and one of my friends who currently works at Space Telescope is going to call me about it tomorrow. He says morale there is awful, and many are looking for outs. They'll be running James Webb, too, so there will be things to do, but still...
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