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Space

Hubble Telescope Hit By Mechanical Failure (bbc.com) 141

Posted by msmash from the roadblocks dept.
The Hubble Space Telescope is operating with only essential functions after it lost one of the gyroscopes needed to point the spacecraft. From a report: The observatory, described as one of the most important scientific instruments ever created, was placed in "safe mode" over the weekend, while scientists try to fix the problem. Hubble had been operating with four of its six gyroscopes when one of them failed on Friday. The telescope was launched in 1990. After the gyro failure at the weekend, controllers tried to switch on a different one, but that was found to be malfunctioning. That leaves Hubble with only two fully functional gyros. At any given time, Hubble needs three of its gyroscopes to work for optimal efficiency.
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Hubble Telescope Hit By Mechanical Failure More

Hubble Telescope Hit By Mechanical Failure

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  • Ouch (Score:3)

    by atrex ( 4811433 ) on Monday October 08, 2018 @03:51PM (#57447396)
    This could be pretty bad news for NASA if they can't manage to jury rig something. Hubble's successor, the James Webb Space Telescope, isn't scheduled for launch until 2021. Though I suppose they could try to do another repair mission on the Hubble like they did in '93 and four other times since (the last was 2009), but, that was back before they retired the space shuttle in 2011. Doing another maintenance run on the Hubble is probably beyond the spec/capabilities of the first manned SpaceX launch, currently planned for mid 2019.

    • Re:Ouch (Score:4, Insightful)

      by rickb928 ( 945187 ) on Monday October 08, 2018 @03:55PM (#57447414) Homepage Journal

      A service call to Hubble is out of scope for the first several SpaceX manned launches. It doesn't provide the same capabilities as the Shuttle at all.

      But Elon might actually offer a solution, or at least offer to offer one.

      • Re:Ouch (Score:4, Funny)

        by Waffle Iron ( 339739 ) on Monday October 08, 2018 @04:12PM (#57447538)

        But Elon might actually offer a solution, or at least offer to offer one.

        I've heard that he has a spare one-man capsule that was designed specifically for rescue missions.

      • Re:Ouch (Score:4, Informative)

        by quenda ( 644621 ) on Tuesday October 09, 2018 @02:40AM (#57449542)

        A service call to Hubble is out of scope

        Hubble had Servicing Missions in 1993, 1997, 1999, 2002, and 2009.
        The 1999 and 2009 missions replaced the gyroscopes. So this was expected.

        The Hubble was being built around the time the Commodore VIC20 and Sinclair ZX80 were released, though the launch was long delayed.
        So maybe it is time to retire it. Perhaps a small ceremony and fireworks display over the South Pacific.

        • The Shuttle was uniquely suited to these missions.

          I doubt the Orion, Dragon, or Starliner have the necessary capabilities.

          You know, the US has only made 4 different manned flight space capsules ever... Interesting. The Russians, really only 3. The Chinese, one. India plans one, and we have three new ones in competition. Russia has one planned also... Not sure the Iranian project is serious.

    • Doing another maintenance run on the Hubble is probably beyond the spec/capabilities of the first manned SpaceX launch, currently planned for mid 2019.

      According to this article from January 2018, [theatlantic.com] the earliest SpaceX is expected to fly humans is December 2019. Boeing expects to fly February 2020.

    • Re:Ouch (Score:5, Insightful)

      by bobbied ( 2522392 ) on Monday October 08, 2018 @04:35PM (#57447710)

      Doing another maintenance run on the Hubble is probably beyond the spec/capabilities of the first manned SpaceX launch, currently planned for mid 2019.

      I fear you are correct. Hubble was/is at the extreme limits of the shuttle system's ability and the last trip was risky enough that they almost didn't do it. Now we have no shuttle.

      I don't doubt Space X could engineer some solution to service Hubble, but the timeframe it would take to develop the capability is likely to be longer than the scheduled replacement's arrival. To do this Hubble service thing, you need to first catch it in orbit (the shuttle used an astronaut on the robot arm for this) so you can work on it, then open it up and move around some large chunks of delicate gear from some kind of cargo area.

      Given the age of Hubble, the cost of such a rescue mission and the projected replacement of the system already scheduled, I'm guessing they use Hubble as best they can with what's left that is still working. It's been a great achievement, but I don't think it's worth it at this point to try and fix the thing. Besides, we all knew the day would come when Hubble would work no more. It's sad, but the time may be closer than we would like to admit.

      • Re: (Score:3)

        by Hadlock ( 143607 )

        It wouldn't surprise me if they devised a device with several gyros that used the soft grapple "docking adaptor" they installed on the service mission to replace the gyros. The Dragon is not rated for more than X time in space but it could be uprated filled with gyros, 10 gyros would weigh substantially less than an ISS payload; and then is docked to the rear of the hubble (soft grapple). AFAIK the optics and solar are fine, it is just the gyros that are prone to failure. They could also re-boost the hubble

        • I don't doubt that someone could create such a device that could do that; however, the problem would be how it would interface with Hubble's systems. I don't think it was every designed with an external port that would work. The last few repair missions involved replacing parts of Hubble's internal systems by opening panels that required human dexterity.

          • Re: (Score:1)

            by Anonymous Coward

            Duh,...bluetooth!

        • I think they have launched something like that as one of their secondary payloads, not their own design, but but one of their customers had a satellite life extender system. The idea being, that the system would dock or grapple an out of fuel comms sat and have enough fuel for stationkeeping on board to extend its service life. Such a thing would necessarily have full orientation control, so there you go, also a fix for broken gyros.
          • The problem I would see is the size of the Hubble relative to the extender. It's not the weight but any thrust to the side would cause a fishtail motion and not very precise. Now the Hubble has a grapple location meant for an external rocket to push it into deep space when it reaches end-of-life. It however is not meant for fine tuned controls that Hubble needs for current operations.

      • Given the age of Hubble, the cost of such a rescue mission and the projected replacement of the system already scheduled, I'm guessing they use Hubble as best they can with what's left that is still working.

        It does make sense to spend the dollars if it'll reap, say, a $billion in positive public relations for a private contractor that pulled it off.

        If only there were a space flight contractor in need of some of that.

        • Well, you are entitled to your opinion. However, I think the new observatory has a better ROI in the PR world than Hubble would going forward. Hubble was great while it lasted but I think the time is fast approaching when it will make sense to retire it and not try to revive it.

          I do feel bad about it, but my feelings of nostalgia about a 20 year old epic achievement aside, it may be time to accept that Hubble is getting VERY old for something in orbit and we can now capture similar resolution images from

    • Re: (Score:1)

      by Raenex ( 947668 )

      Hubble is probably beyond the spec/capabilities of the first manned SpaceX launch

      We can land probes on comets and asteroids. Surely we can land a gyroscope attached to a magnet and stick it on the Hubble?

      • You know I was thinking the same. In 2018 we should be using semi-automated or at least remote controlled robots for things like this.

        • We should use robots. But we waste our budget putting men into the space station.

          And for the funds wasted on the Shuttle, there could be dozens of space telescopes. Well a few anyway.

          And the Webb would already be launched.

          • Yeah the shuttle was an absolute disaster financially. IIRC it was just a dick competition with Russia.

            • Re: (Score:3)

              by dryeo ( 100693 )

              It was a good idea, the Air Force made demands on performance (IIRC, flying over the USSR and returning to its launch site in one orbit) that crippled it for routine missions. As well the engines needed much more servicing then planned.

    • Hubble is not just a NASA project. It would be bad for ESA too.
    • Why would it be out of spec? Dragon can be launched on lunar free return trajectory, that's way beyond what is needed to meet up with Hubble and way beyond what Shuttle could have done. Downsides would be that there is no airlock, so entire capsule would have to be depressurized for EVA, but that's an inconvenience not a technical showstopper. There is also no robot arm, so manual capture required, but that's very much doable, I think they did the same with shuttle at least once, with a completely defunct a

    • Sierra Nevada has a better chance of servicing Hubble than SpaceX. Their Dream Chaser vehicle has the required attributes, with the only drawback being that it doesn't exist yet.

    • Re: (Score:1)

      by Anonymous Coward

      "[James Webb] isn't scheduled for launch until 2021"

      I wouldn't bet on it launching then either. We've seen this show before, and its disturbing that we still bother to buy tickets to the next show. If I remember correctly it has blown past about 4 delivery dates/budgets so far. Each time asking for "just" a few more years and another billion or two. I doubt a servicing mission would be very feasible with any of the current manned vehicles in development as none are really equipped for EVAs, even Orion w

    • Re:Ouch (Score:4, Interesting)

      by Miamicanes ( 730264 ) on Tuesday October 09, 2018 @12:47AM (#57449362)

      It's even worse than that. JWST isn't a real REPLACEMENT for Hubble. It'll be able to do things that Hubble can't, but there are even MORE things Hubble can do that JWST won't ever be able to do.

      The fact is, we don't have the ability to launch a new satellite as big or as heavy as Hubble... and AFAIK, there are no rockets even under development that will be capable of delivering something as physically BIG as Hubble (or the existing ISS modules) into orbit. Hubble and the existing ISS modules are all we have, and all we're LIKELY to have for DECADES. They're literally irreplaceable within the span of our lives, and as such, deorbiting them is, IMHO, wantonly reckless and irresponsible. If Hubble's telescope functionality dies before we have the ability to send a refurbishment mission, we should be ready to DO the deorbiting mission on 18 months' notice... but always and only as a last-ditch "plan B" if we don't get the ability to launch a robotic or manned servicing & refurbishment mission first.

      From what I understand, if Hubble failed completely and became totally uncontrolled tomorrow, it would be at least a decade before it fell far enough to present imminent risk of uncontrolled reentry. If we made even a token attempt to send a robotic mission to boost it into a higher orbit, we could easily add another decade to that. SpaceX might not be ready to fly a refurbishment mission to Hubble within the next 3-5 years... but it probably COULD be ready to do it 6-10 years from now (if it had a firm commitment from NASA), and will probably be capable of doing it within 10-15 years regardless of what NASA does (and knowing Musk, would probably invoke maritime salvage law & refurbish Hubble ITSELF as a commercial venture if NASA couldn't/wouldn't do it).

      Frankly, I think 90% of NASA's sense of deorbiting-urgency is precisely BECAUSE they'd rather see things like the ISS and Hubble get intentionally destroyed than risk allowing someone else to metaphorically grab them from the curb before the garbage truck arrives.

      • ...and knowing Musk, would probably invoke maritime salvage law & refurbish Hubble ITSELF as a commercial venture if NASA couldn't/wouldn't do it.

        This is key. The Hubble has immense value. Even if Musk wouldn't get mountains of accolades just for fixing it, the ROI for doing so on his own nickel would more than pay for itself as long as it doesn't suffer another failure.

      • Frankly, I think 90% of NASA's sense of deorbiting-urgency is precisely BECAUSE they'd rather see things like the ISS and Hubble get intentionally destroyed than risk allowing someone else to metaphorically grab them from the curb before the garbage truck arrives.

        I think you're wrong. It's because they could build and send in replacements, multiple in the case of Hubble, quicker and cheaper than doing manned missions to refurbish the old stuff in orbit. Anybody who could go up there and grab them, would be able to put a newer better one up instead for less money.

        Car analogy: It's like the old truck. It was a good truck, and when it runs, it still does its base job. However, it's old and repairs and maintenance are getting more and more frequent and more costly. So m

        • Better analogy: you own a big, huge, old London-style double-decker tourist bus on a small, remote island. Say, somewhere in the South Pacific. Twenty five years ago, the bus was delivered to the island by a unique amphibious cargo ship capable of surviving the high seas, rolling up onto the beach, and driving it off before departing to haul big things to other remote islands.

          The bus is now old and decrepit... but amphibious ships like the one used to deliver your bus no longer exist... they had some really

      • Update: I was wrong about maritime law & salvage rights. Apparently, the US isn't a signatory to the UN treaties governing maritime salvage, and takes the position that a) sunken US government ships that sink on the high seas remain the exclusive property of the US in perpetuity and are never implicitly abandoned; b) salvage rights to ships that sink in US waters remains with the original owners in perpetuity... and solely belongs to the US government if the wreck gets salvaged by anyone else; and c) ju

    • Re: (Score:2)

      by epine ( 68316 )

      This could be pretty bad news for NASA if they can't manage to jury rig something.

      What's the pressing demand for 100% space telescope operational continuity?

      Are there experiments in progress which demand a precisely timed sequence of images updates, no frame loss allowed?

      Or are you just projecting your personal wrath over YouTube frame drop after you shelled out for a $5000 graphics card? (Never mind $10 billion.)

      • Re: (Score:2)

        by atrex ( 4811433 )

        Or are you just projecting your personal wrath over YouTube frame drop after you shelled out for a $5000 graphics card? (Never mind $10 billion.)

        I have no idea what you're talking about. I simply commented on the sad state of affairs of an important, unique, and historic piece of science equipment potentially becoming permanently inoperable with no replacement or potential fix viable in the immediate future. Sure, it was only a matter of time until it broke down, but, at least the last time it broke down we still had a shuttle they could send up to fix it.

        Or maybe you're one of those who think pure science is a complete waste of money and everyt

    • Hubble has 4 reaction wheels and 6 gyros, giving it (when they're all working) amazing pointing accuracy.

      Two of the gyros were replaced in the first servicing mission.

      One of the reaction wheels was replaced in the second service mission.

      The third service mission had to be split into two parts - 3A and 3B (I have the 3A mission gimme cap here on my desk) - and 3A replaced all six gyros, as four had failed, including the two replaced during SM1. Having only two gyros caused NASA to rewrite the software, whic

  • It's still early to talk of a rescue mission, but I'm surprised TFA doesn't even mention it. Of course, without the shuttle, and with SpaceX and Boeing unlikely to fly humans until sometime around 2020, It's likely to remain hobbled [wah wah] when the Webb telescope is launched in 2019. So fixing it will depend on the cost/benefit for what Hubble can do compared to Webb.

    • Whoops, make that 2021, not 2019 for the Webb launch. Still, I'll bet Webb is in orbit before Hubble is fixed, if it ever is.

      • Re: (Score:3)

        by Raenex ( 947668 )

        Whoops, make that 2021, not 2019 for the Webb launch.

        Who can blame you? Hard to keep up with every time they delay the Webb launch for another 2-3 years.

        • Re: (Score:3)

          by tri44id ( 576891 )
          And once the JWST gets unfolded, if it succeeds at unfolding at all, you won't have to worry about repair/refurbish missions, even if SLS or BFR could take a crew out to its location. Its coolant tanks aren't designed to be refilled, and parts that are bolted into place on the Hubble are glued permanently. It would take a saw or a torch to remove anything you wanted to replace. After a few years of awesome science, it becomes just another metallic asteroid. Could its mirror and sunshade justify a salvage

          • That seems an utter travesty, especially in light of the burgeoning reusable rocket industry that promises to rapidly make servicing things in space routine. (really, doing anything in space)

            Though... Remove the sunshield, and you should be able to fit the whole thing inside the bay of a BFS cargo ship with meters..ish to spare (in diameter, far more in length). If they make that space pressurizable, the whole giant thing could be captured, rebuilt at leisure in a spacious pressurized environment over the c

  • Comment removed (Score:3)

    by account_deleted ( 4530225 ) on Monday October 08, 2018 @03:56PM (#57447422)
    Comment removed based on user account deletion

    • And that's why you should never spend our lunch break reading in a heavily shielded bank vault. The universe is always on the look out for new and exciting ways to mess with you!

      I always wondered though - did the guy really not have a second pair of glasses? Or know where the optometrist was located to find another pair that was at least adequate enough? I suppose really the over-dramatic response was likely shock as the reality of the situation finally found a chink in his carefully constructed emotiona

      • Comment removed based on user account deletion

        • Hey, I saw the size of those shards - more than enough to see through to navigate the city. Or read a book, though the eye strain would be hideous.

          And please sir - one must never acknowledge the existence of "authors" or other such active gods in the universe, nor the constraints of "episode" they impose, lest the power of the "plot device" render all further discussion moot.

  • Iirr the gyroscopes all have issues with their gyroscopes' bearings, that were not discovered in earth-based duration tests.

    Cosmic rays erode the surface of the metal ball bearings, causing them to fail eventually way before their predicted life span.

    They changed to ceramic bearings since which solved the problem.

    Source: some youtube vid i saw a while ago.

    • Re: (Score:3)

      by Kjella ( 173770 )

      Iirr the gyroscopes all have issues with their gyroscopes' bearings, that were not discovered in earth-based duration tests. Cosmic rays erode the surface of the metal ball bearings, causing them to fail eventually way before their predicted life span. They changed to ceramic bearings since which solved the problem.

      They've found several things:

      One lesson learned was that gyros assembled using pressurized oxygen to deliver suspension fluid were prone to failure due to electric wire corrosion. Gyros are now assembled using pressurized nitrogen.

      But ultimately all the gyros were replaced in the final service mission in 2009, before that they were also replaced in 1999. These new ones were supposed to last longer but it seems ~10 years is still all we get. I wonder if the Dragon can be retrofitted for spacewalks.. I don't think you could use the same airlock as for docking, they'd need full vacuum spacesuits and June next year is just supposed to be a test flight...

      • Re: (Score:2)

        by Agripa ( 139780 )

        I wonder if the Dragon can be retrofitted for spacewalks.. I don't think you could use the same airlock as for docking, they'd need full vacuum spacesuits and June next year is just supposed to be a test flight...

        There is no room for an airlock so the whole craft would need to be depressurized like the Apollo era craft.

    • I believe Scott Manly did a youtube video about it.

  • ... and hurry.

    • Re: (Score:1)

      by Anonymous Coward

      Maybe they should continue to concentrate on getting it right, considering that it will be positioned in a Lissajou path around the Earth-Sun L2 point. That is out of range for any servicing mission in the near future, especially given that it is not designed for that.

      • Re: (Score:3, Informative)

        by CaptainDork ( 3678879 )

        How embarrassing. [wolfram.com]

        Lissajous curves are the family of curves described by [...] parametric equations ...

        Go away. [nasa.gov]

        The James Webb Space Telescope will not be in orbit around the Earth, like the Hubble Space Telescope is - it will actually orbit the Sun, 1.5 million kilometers (1 million miles) away from the Earth at what is called the second Lagrange point or L2.

        • Re:James Webb ... (Score:4)

          by mhotchin ( 791085 ) <slashdot@NOSPam.hotchin.net> on Monday October 08, 2018 @06:01PM (#57448142)

          If you are trying to refute the GP, you are doing so very, very badly. The G.P. is correct, and nothing you said actually contradicts him. The only thing he said incorrectly was that the craft will orbit the point - it doesn't, it orbits the sun, but it does move around the Lagrange point in a semi-stable manner.

          Orbits are, *of course* curves described by parameters. It so happens that in the co-ordinate system centered on the Lagrange point, and aligned to the sun, that the movement of spacecraft around the Lagrange point is, in fact, described by a Lissajou curve.

          Since this isn't a scientific paper, I'll direct the curious here:
          That wiki thing [wikipedia.org]

  • Do we really need Hubble that badly anymore?
    Apparently adaptive optics technology is allowing ground-based telescopes to surpass Hubble's capability.
    https://www.airspacemag.com/sp... [airspacemag.com]

    Rather than firing up an expensive space mission (I remember each shuttle mission was $500M), would it genuinely be better to just take that money and build or retrofit a ground-based telescope with adaptive optics? A telescope that you could easily maintain thereafter?

    This doesn't help with wavelengths of light that don't go through Earth's atmosphere, but that's not what Hubble does. Seems like we could do without Hubble nowadays.

    --PeterM

    • Re:Ground based telescopes with adaptive optics (Score:5, Insightful)

      by Immerman ( 2627577 ) on Monday October 08, 2018 @04:44PM (#57447774)

      One of the biggest advantages that an orbital telescope can provide (beyond avoiding atmospheric distortion) is a stationary platform for targetting distant objects and long exposures. Any telescope on Earth is rotating at a constant rate of 1 revolution per day, as well as being plagued by the many vibrations traveling through the Earth itself. You can build it on a moving platform so that servos keep it focused on a specific point in the sky, at least while that point is above the horizon, but then you introduce all the vibrations of the tracking mechanism, which makes it impossible to take clear images of fine detail. Rather like trying to use a high-power telescope while holding it in your hands - all you'll ever be able to see is a blur.

      An orbital telescope though stays focused where you point it. It orbits the planet, but the parallax from that is irrelevant over long interstellar distances, and it only takes a little help from vibration-damped precision gyroscopes to keep gravitational fluctuations, solar wind, etc. from causing it to start spinning.

      • While those are all problems to be contended with they all have engineering solutions which have resulted in images surpassing the quality of Hubble's results. The remaining issue is access time due to the sun being up for a portion of the day, and weather ruining some nights.

        https://www.popularmechanics.c... [popularmechanics.com]

        • Again - those are photos of nearby objects - they don't need long exposures. Neptune is practically right next door, and even NGC 6388 is still within the Milky Way (and they don't share a Hubble photo of that for comparison - here's one that seems to show far more detail: https://www.spacetelescope.org... [spacetelescope.org] )

          • Again - those are photos of nearby objects - they don't need long exposures.

            I see you've not taken photos of these objects before. They most definitely do need long exposures, and the wonderful thing about space is you can take those exposures whenever you want and work them together afterwards.

            Also while you're comparing things remember that you're comparing decades of experience from the Hubble with "first light" from the adaptive optics in the article.

            Engineering solutions exist and will make the hubble obsolete. They will be dwarfed by the James Webb though.

            • They may indeed soon make the Hubble obsolete in most respects, which is a good thing since it frees the Hubble up for the things where they can't compete (assuming it lives that long). But the technology *today* isn't quite there yet. And I seriously doubt any ground-based telescope will ever be suitable for doing spectral analysis of exoplanet atmospheres. Nor be able to compete with orbital stability for photographing things near the limits of the observable universe. Not even against telescopes 30 y

    • In concrete terms, ESO/ESA VLT surpassed Hubble by quite some margin. But if we can fix Hubble with a *relatively* cheap robotic mission, it would make economic and scientific sense.

  • "Hubble had been operating with four of its six gyroscopes"

    Gyroscope count: 4

    "...when one of them failed on Friday."

    4 - 1 = 3
    Gyroscope count: 3

    "After the gyro failure at the weekend, controllers tried to switch on a different one..."

    3 + 1 = 4
    Gyroscope count: 4

    "...but that was found to be malfunctioning."

    4 - 1 = 3
    Gyroscope count: 3

    "That leaves Hubble with only two fully functional gyros.'

    But the count is 3, isn't it?

    "At any given time, Hubble needs three of its gyroscopes to work for optimal efficien

    • Re: (Score:2)

      by Mascot ( 120795 )

      Bad summary, as usual. Reading TFA it seems they only operate with the number of gyros required, keeping the remainders in reserve to drag out the lifetime of the HST. The scenario looks to be that one failed, and when they tried to bring the (final) spare online, it turned out to be misbehaving as well.

    • Hubble had 6 gyroscopes originally, and all 6 were replaced during the last servicing, but two of those had already failed. Those aren't coming back. (6-2=4. Total.)

      3 of the 4 remaining functional gyroscopes were actually in use, as required for optimal performance, with one left powered down as a backup in case one of the remaining three failed. Like hard drives, the chance of failure is much greater when they're active. (4=3 active + 1 backup)

      One of the active gyroscopes failed (3-1=2), so they tried t

  • >> Hubble had been operating with four of its six gyroscopes when one of them failed on Friday

    So 4 -1 = 3.

    >> After the gyro failure at the weekend, controllers tried to switch on a different one,

    So 3 + 1 = 4

    >> but that was found to be malfunctioning.

    So 4 -1 = 3

    >> That leaves Hubble with only two fully functional gyros.

    3 != 2

    • No, it's

      Hubble had been operating with four of its six gyroscopes when one of them failed on Friday

      So, 6 - 1 == 4

      After the gyro failure at the weekend, controllers tried to switch on a different one, but that was found to be malfunctioning. That leaves Hubble with only two fully functional gyros

      And, 6 - 2 == 2

  • Two gyros might work (Score:3)

    by g01d4 ( 888748 ) on Monday October 08, 2018 @04:19PM (#57447614)

    That leaves Hubble with only two fully functional gyros. At any given time, Hubble needs three of its gyroscopes to work for optimal efficiency.

    I found this [newscientist.com] from thirteen years ago:

    In the meantime, engineers have continued planning for the two-gyro mode ... Tests of the mode, in which onboard computers only used data from two gyros, showed the resulting images were nearly identical to those taken with three gyros. One of scientists' main concerns about switching to a two-gyro system had been that âoejitterâ in the telescope would produce blurry images.

    • The devil's in the details though. Literally in this case. "Nearly identical" is great for taking pictures of local planets creating images dozens or hundeds of pixels across, but when you're trying to photograph other stars or galaxies, which may only constitute a handful of pixels, then that "nearly" identical could show itself in a substantial amount of lost detail.

      • Re: (Score:2)

        by mentil ( 1748130 )

        The devil's in the details though. Literally in this case.

        Damn Satan, messing with our space telescopes! Clearly we didn't sacrifice enough Slashdot virgins to appease him.

    • I doubt it would work that well. With only two gyroscopes in operation, there's an axis along which rotation will not be measurable by either gyroscope. They can probably use other methods to figure out the approximate direction the satellite is pointing, so really big movements probably won't be a major problem. But it will likely be really hard to keep the satellite from drifting along that axis during any long exposures. Short exposures shouldn't pose a problem, but longer exposures definitely will.
    • The gyros are not for measuring the rotation, you can do that just fine by looking at the stars. The gyros are for actually moving the satellite, you turn the gyro one way, the satellite turns the other way, conservation of angular momentum. With only 2 gyros there is now one axis where rotation cannot be precisely controlled.

  • An opportunity (Score:2, Funny)

    by PPH ( 736903 )

    The aliens can move their mother ship up from Pluto to a position behind the moon while we aren't looking.

  • Need a ba330 ( or even a BA Sundancer ) with a tug to push it around. That could be used to move around leo, esp from ISS to another private space station.

  • Damn... (Score:1)

    by sad_ ( 7868 )

    They sure don't make them space telescopes like they used to.

    What about right to repair?

  • This piece of marvel been in orbit since the 1990s and amazing it lasted this long. But as with any equipment it will wear out. Without the shuttles it will be hard to perform any kind of major mechanical repairs so they may have to bite the bullet and plan on a replacement soon.

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