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Hubble Space Telescope Goes Into Safe Mode
Generic Specialist writes "There is an article on the BBC web-site reporting that the Hubble Space Telescope has finally shut itself down due to the failure of a fourth gyroscope. For some time it has been running on the minimum three out of its six gyroscopes, and on Saturday the failure of another one sent the telesope into its safe mode. We'll have to wait until after the next servicing mission, due next month, before any more science can be done.
"
The gyroscopes allow the operators to point the Hubble. Which is why a minimum of 3 are required. There is no ability to change the Hubble's orbit. To do that would require dragging it into the cargo bay as they did on the repair mission last time and use the shuttle to boost it into a higher orbit.
As the Hubble sits there only Isaac Newton is controlling its orbit. If a large solar flare occurs, hopefully the earth will be between the hubble and the event, otherwise there's little the operators can do, other than close the doors, possible put the processor into some sort of safe mode, and hope for no bit-flips.
It was always expected to have to do a minimum of 2 servicing visits to the hubble for these type of things. Originally they were intended to upgrade the hardware (changing a tape storage device to solid state, etc..) but they always suspected that things like gyros would need changing out.Everyone here seems to be forgetting that space is a particularly harsh environment. Especially considering that in Low Earth Orbit (LEO) a satellite is going to shadow to sunlight (~ -200 degrees to ~ +200 degrees farenheit) many times a day. These environment changes tax even the best engineered hardware, and these problems shouldn't surprise anyone.
Regardless of cost, I think Hubble was a tremendous investment. Knowlege for the sake of knowlege. I like it.
The more "pure-science" that is done in the world the better (science that can not be perverted into a weapon).
Ignore Alien Orders
> Among the interesting points: several of the initial gyros on the scope were engineering test
> models that already had tens of millions of hours of use.
That statement, in itself, is enough to discredit your whole post. FYI, 24*365 = 8760, meaning each year is composed of roughly 8760 hours. That means that, in order to reach "tens of millions" of hours of use, these gyroscopes would have had to be spinning for over 1100 years (that is, just to reach the 10,000,000-hour mark)!
Get real.
--Corey
Not only will they not deserve liberty or safety, Mr. Franklin, they will be DENIED both!
My impression is that, at least as of the time they were designing it, nobody knew how to make a really reliable gyro. Therefore, they built in lots of redundancy (3 spares!), and figured they would have time to replace the spares before they all ran out. Remember, the telescope was intended to be serviced at regular intervals, for upgrades of instruments if nothing else. Unfortunately, there seems to have been a miscalculation, either in the reliability of the the gyros, the reliability of the space shuttle, or both.
There is something one should remember when looking at space equipment failures: whoever puts it up is severely limited in how thoroughly they can test it. Essentially, anything that gets put up has to be considered an alpha version. Unfortunately, there is no beta. I am astounded that much of the stuff that gets sent up works at all; that it does is a real testament to the care and skill of those who build it.
My mind is getting a bit fuzzy with age, but I think the Hubble mirror is 200". Somebody will get me on that if I'm wrong. I don't see how it could be replaced in orbit. I would guess that that's why they didn't replace the mirror on the first repair mission.
;)
The housing? I would think that there is some sort of bolt-on dust/space junk/micro meteor shielding that can be replaced.
I would love to see Hubble working for decades. I would love to do an EVA to help repair the darn thing.
then it comes to be that the soothing light at the end of your tunnel is just a freight train coming your way
After getting in touch with the gyro craftsman ("Hans"), the project decided to try to turn gyro 1 on and off again. This was done about 1:00 local time. This did not seem to do any good. The start up cycle went up to about 500 milli-amps (over 700 ma was expected) and then down to the 350 ma level it had been at after the failure this morning. There was no indication that the gyro moved, it certainly did not get into sync. At this time, there is not a good understanding of what actually failed. The "lube patch" theory is now not seen to be completely consistent with the data. The gyro engineers at GSFC and Allied will be reviewing the data and looking at a wider range of possible failure scenarios over the weekend. No further attempt will be made to turn the gyro on until next week.
There will be a meeting/telecon sometime Monday afternoon to review the data and analyses. Meanwhile, the working expectation is that we will stay in zero gyro mode until SM3A. The instruments will be recovered from safe to hold next week. The current plan is to work through the plans for the recoveries on Monday and carry them out on Tuesday. The recoveries will be done in real-time, but an RTCS will be needed for the FOC recovery. The project will be reviewing the situation to identify any housekeeping activities necessary during the period before SM3A. They are also reviewing the process for closely monitoring performance in the zero gyro mode, since this will be by far the longest time we have been in this mode.
The Hubble Space Telescope has shut itself down preventing astronomers from making any observations of the Universe.
;-)
Ahem.. Yes, well.. Did they suddenly all go blind?!!!
A dog-bone shaped satelite with a pair of manipulator arms about to rip it to shreds? :-)
"Pinky, you've left the lens cap of your mind on again." - P&TB
"I can see my house from here!" - ST:
Gyro-99FX3dW00 caused a general protection fault in MSHBLSAT.dll. It may be possible to continue operating normally. Press enter to return to MS-Space and wait for your telescope to recover, or press ctrl-alt-del to send it spiraling down to earth in a heaping flaming mass.
Bad things often happen to good people,
It is up to them to see that they remain good.
It seems like one thing or another has gone wrong with Hubble since it was first put into orbit. How reliable was the design expected to be compared to how reliable it has been?
;)
It's not that easy.
HST was designed to be modular, and in that sense the lifespan is long; each module can be replaced.
The design takes into consideration that the individual modules would need replacement.
Another thing; compared to the amount of money spent on warefare, the amount used on space exploration is peanust.
Anyhow; it is used a lot and constantly bombarded by particles. Give it a break
Given the fact that any repair mission into space is gonna be pretty expensive and potentially dangerous, we should try to build self assembling/repairing structures ... I'm pretty sure this is what Transmeta is up to (the stories about chip development you keep hearing are just decoys fed to the press) ... watch out, the nanobots are coming for all of us ...
./: Wow, if I only had a beowulf custer of those nanobots ...
...
Ob
Sorry, 'couldn't resist
Does anybody know why the gyroscopes failed, or what plans are being made to avoid the same problem when they are serviced?
Will there be any problems with the telescope while it's in safe mode? I assume it's all closed up to protect itself - can operators still send it commands to control its orbit & possibly protect itself from solar flares? How will the lack of any gyroscopes affect operator's control of it?
Given the emphasis on redundancy, it's pretty amazing that FOUR gyroscopes ended up failing. Are the four gyroscopes all of the same type? I wonder if they all failed the same way. Does this point out the typical "RISKS" failure where somebody has provided redundancy but using identical equipment with the exact same weaknesses (i.e., redundant in number but not in character)?
If so, do they have any plans to try and avoid the same problem?
Assuming it went into deep safemode, the scope is fine. The aperature door will close and the scope will keep position in space. Safe mode is something Hubble's controllers understand very well...
Check out Eric Chaisson's The Hubble Wars for a good description of just how FUBARed the Hubble really is. Among the interesting points: several of the initial gyros on the scope were engineering test models that already had tens of millions of hours of use. A number failed before the last repair mission: they were only 1 gyro away from safe then.
Chaisson (ex-Space Telescope Science Institute high-muckity-muck) was more than a bit critical of the entire design process. Even beyond the the well-known mirror and solar panel problems, the number of design flaws and construction problems were amazing. For example, while it waited for launch nobody could find the documentation that stated that the secondary mirror had ever been installed. They had to tip the scope and build a $BIGNUM "diving board" so someone could climb into the scope and look.
"Seven Deadly Sins? I thought it was a to-do list!"
Many /.ers were asking for details on Hubble. Well I did some diggig up and came up with this Hubble history:
.. can any one give more details ?
--Co-operative program of NASA and ESA
--Design lifetime = 15 years,with a 3 yr cycle of on-orbit service
--Launched by Discovery(STS-31),1990
--2 service missions so far,1993, and 1997
--1993 service replaced two gyroscope Electronics Control Units (ECUs)and fuse plugs for the gyroscopes
But no details on the latest failure even at stsci.edu
Some Links :
http://www.stsci.edu/hst/
http://amazing-space.st sci.edu/service/service-science.html
Manifest
... "follow me" the wise man said, but he walked behind
Well you already have your wish. The US Gov't has approved funding on the 'Next Generation Space Telescope', and work is already underway. The target launch date is sometime around 2006-2008.
The NGST will have a 10 meter infrared mirror, and be placed in a LaGrange point out past the moon.
For info:
http://www.ngst.stsci.edu/
Start placing your bids now to buy whatever is remaining. Whether it's 2003 or 2010.. place a bet whether you'll be able to afford to send someone up to put your own modules on it...
Of course, if by 2010 there are commercial launches which can put a larger mirror up there then maybe that thing being in orbit won't be an advantage.
Another thing; compared to the amount of money spent on corporate welfare, the amount used on (regular citizen's) welfare is peanuts. Ergo
which, to me at least, sounds exactly the opposite of fair. But then, I'm not the one making all the rules around here...
DO NOT LEAVE IT IS NOT REAL
From the following comments on NASA's mission site, it sounds like the gyros are just too new and different:
:-)
"Why aren't the gyros working?
The Hubble team believes they understand the cause of the failures, although they cannot be certain until the gyros are returned from space and taken apart. Based on nearly one and a half years of intensive chemical, mechanical and electrical investigations, the team believes that the thin wires are being corroded by the fluid in which they are immersed and ultimately this corrosion causes them to break. The fluid is very thick (about the thickness of 10W-30 motor oil), and in order to force this fluid into its float cavity, pressured air was used. The team believes that eventually, oxygen in the air interacted with the fluid to create a small amount of corrosive material and the wires were partially eaten away. Sometimes the wires were strong enough to carry electricity and some-times they were not and they broke. Pressurized nitrogen is now used instead of pressurized air. Using pressurized nitrogen eliminates the introduction of oxygen into this fluid."
Sounds like a much more forgivable error than confusing pounds with Newtons
--
"You can't get something for nothing." - my grandfather, on the stock market and Reaganomics.
Engineers working on the Hubble space telescope are reporting their initial findings, according to the a Reliable News Service. The first engineer on the scene is quoted as seeing: "Microslop Hubble Space Telescope OS V1.0" License has expired, please contact your Microslop representative for upgrade. Or pressurise the DoJ into getting it's teeth out of Bills' arse for continued operation of this Microslop installation." The screen is a calming shade of blue. Engineers have been equipped with a LILO boot disk and some downloaded copies of the world famous Linux Operating System; it is expected that the newly equipped Hubble telescope will now run 15% faster. "Kernel tweaks", a computer nerd term for messing with Linux's internal operation (also know by some as "make and pray") will be applied remotely by Linus Torvalds, creator of Linux to the world and "Saint Linus" to Linux users. Upon mission completion, it is expected that Torvalds will be unequivocably given a Nobel prize, and more than likely a knighthood. Following the Linux installation, resources hogged by the previous OS will be utilised to run pattern matching algorithms for new star clusters, analyse SETI-like data on the fly, solve world hunger, bring about world peace, and provide a correct answer to the question "does my bum look big in this?"
Strong data typing is for those with weak minds.
Yeh, science sucks, if people hadnt invented computers I'd be happier now, as I wouldnt have to read your luddite tripe!
Everyone else: sorry about the flame, but I'm having a hard time getting a grant for my science career. Some people (governments) are so damn short sighted.
-Yarn - Rio Karma: Excellent
Just thought I would point out 2 things related the Hubble and the reservicing mission. A) The reservicing mission was actually supposed to take place on october 14th, but due to shuttle problems it had been delayed. Had the mission been done when it was originally planned, there would not have been such a long downtime. B) It was *known* that the gyros were going to fail. It was hoped that servicing mission 3 A would be completed in time to replace the bad gyro, but obviously it wasnt. However this was not due to bad planning by NASA, since is has been widely known here (Goddard Space Flight Center) that the gyros had a limited life span. Nothing lasts forever.
I also worked on Servicing Mission 3B, which is supposed to fix the NICMOS Cryo cooler, and add some additional hardware. NICMOS is an infared camera, good for seeing through dust clouds and whatnot. Who knows when that mission is going up now.
Remember, the Hubble was supposed to be launched in 1986, shortly _after_ the Challenger (RIP) disaster.
Hubble sat around for a few extra years and had plenty of time to age. The whole problem with the optics on Hubble was that sitting on earth too long deformed the mirror.
IIRC, Hubble is about 15 years old. It was one of the first (if not the first) satilites (sp?) designed to be maintained by the shuttle. Hubble has been in planning since before the first shuttle flight, so we're dealing with some 20+ year old technology. I would think they are slowly upgrading the old systems with newer tech as they replace them.
Not sure about the lifespan.
then it comes to be that the soothing light at the end of your tunnel is just a freight train coming your way
When was the last time a movie saved millions of lives? I'll tell you: never.
Science, on the other hand, has saved uncounted millions (maybe billions) of lives. If it weren't for science, we'd all still be worried about contracting smallpox, or the Plague, or smallpox, or even influenza!
. . . and now I'm sure some smart-ass is going to pop back with a quip about how people still die of those diseases in the Third World. That's not the fault of Science -- blame your local politicians for that one.
But here's a simple test to see how science has benefitted you: if you disagree with the idea of spending money on scientific research, check your age below and act accordingly:
- If you are younger than twelve: work sixteen hours a day. Eat miserable meals consisting largely of uncooked roots and half-rotten meat.
- If you are between thirteen and sixteen: get married and start producing children as quickly as you can. Eat miserable meals (see above).
- If you are between sixteen and twenty: play russian roulette with two bullets if you're male (to simulate farm accidents and general illnesses). If you're female, use three bullets (to simulate dying in childbirth and general illnesses). Eat miserable meals and work too much.
- If you are between twenty and thirty: break several bones and joints, in order to better imitate nonexistent medical care (injuries normally accrue over a lifetime, but we're playing catch-up here). Eat miserable meals and work too much.
- If you are over thirty, commit suicide, as you should already be dead.
Now, that'll help you get a grip on what life is like without the benefits of science. If you still feel that science spending in "wasted" after doing this little experiment, then I'll congratulate you for the strength of your beliefs.