[HN Gopher] Hubble Space Telescope is back online after software...
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Hubble Space Telescope is back online after software glitch
Author : wglb
Score : 167 points
Date : 2021-03-13 03:55 UTC (1 days ago)
(HTM) web link (www.space.com)
(TXT) w3m dump (www.space.com)
| jeffgreco wrote:
| I'm continually impressed by space missions that last several
| times their original life expectancy - the Hubble was expected to
| last 10-15 years and yet here we are 30+ years later expecting at
| least that yet to come.
| supernova87a wrote:
| Well, that is one way to do it. I think it was necessary for
| HST because it was such a complex instrument that had to be
| capable of doing many things, and reliably -- because
| specifically you have to have a mirror of a certain size to
| make it worth it, and so it calls for a certain level of
| engineering reliability (and cost).
|
| On the other end of the spectrum, the Mars programs (lately)
| were incentivized to do the opposite -- cheap, fast, and good,
| even if some of them fail.
|
| Different circumstances may call for different incentives.
| throwawayboise wrote:
| Except for that part where it was useless after it was
| launched, until an expensive and unplanned repair mission was
| undertaken.
| qbasic_forever wrote:
| It proved Hubble right about the expansion of the universe,
| so all in all I think we can say with absolute certainty it
| was a smashing success.
|
| Apparently the total cost for Hubble is on the order of 10
| billion. That's just a fraction of what a tech company like
| Apple makes every quarter, so I think it was a totally
| reasonable expense relative to its discoveries.
|
| And luckily we learned building giant, precise mirrors with
| 1980s technology maybe wasn't the best decision. The James
| Webb design is totally different and hopefully less prone to
| such problems.
| callesgg wrote:
| People are scared and want to save their asses so they make
| super low estimates. That way it sounds really good in the
| media when things keep working.
|
| I used to do the same when I did software development "I will
| be done with that in 2 days" then proceeded to build the thing
| in 2 hours chill 3-4 hours and hand it in earlier than
| expected. Everyone was happy.
| ghaff wrote:
| Underpromise. Overdeliver. You didn't have to do a crunch and
| the people waiting got something ahead of the deadline.
| That's my practice whenever possible as well :-)
|
| As to your related point, I probably wouldn't use the term
| "scared." But, yes, there are a lot of incentives to
| meet/exceed goals and strong disincentives to fail by not
| meeting a somewhat arbitrary lifetime of a probe. Of course,
| some probes have clear primary objectives and you want to hit
| those but you may not want to "promise" you can hit a bunch
| of less important secondary objectives as well even if you
| think you probably can.
| sephamorr wrote:
| There is truth to this in aerospace: components will be
| qualified to the design life of the vehicle, but the
| qualification campaign is intentionally conservative to
| envelope all possibilities and uncertainty. When the actual
| conditions are more benign, more life can generally be
| expected.
|
| Additionally as another case, Hubble has been continuously
| losing gyroscopes since it was first launched. Some or all
| gyros were replaced during most shuttle servicing missions.
| Seeing the writing on the wall for servicing missions post-
| Columbia, NASA developed software to operate with fewer gyros
| at a time, allowing for fewer to be spun up at any time, but
| importantly, allowing for the telescope to continue to
| operate after more than 3 of 6 gyros had failed. The key here
| is that engineers can often coax more performance out of a
| damaged (or otherwise limited) subsystem given the incentive-
| this has been the case in my aerospace experience, and seemed
| mirrored with Hubble too.
| hn_throwaway_99 wrote:
| > People are scared and want to save their asses so they make
| super low estimates. That way it sounds really good in the
| media when things keep working.
|
| I think that's an unnecessarily pessimistic take. Any system
| can have its life expectancy modeled over a range, e.g. a 99%
| chance it will survive 1 month but only a 50% chance it will
| survive to 1 year. When you're just giving one number to the
| media or other stakeholders, e.g. "expected life span", (or,
| for that matter, a single estimate to your boss), to be able
| to give a value with high confidence you will have to pick a
| number that is in the 99%-ish range, which means there is a
| good chance your system will survive much longer.
| ISL wrote:
| There is a good reason for that. In order to have an
| amalgamation of systems with design life of a given duration,
| every component must have a design life of much, much longer.
| When you get lucky, a system can go for a _really_ long time
| relative to its design life.
|
| Great examples of this are Spirit and Opportunity. The latter
| failed at ~61 times its specified design lifetime.
|
| Having been a small part of some space-mission design and
| larger science collaborations, I can state with confidence that
| you _really_ don 't want your subcomponent to be the one that
| causes a failure.
| qbasic_forever wrote:
| And Voyager 1 and 2 are still zooming as far away from our
| solar system as they can get and happily sending back teeny
| bits of data every now and then. Pretty wild to think their
| voyages are now over 40 years old.
| shakna wrote:
| Not just one way communication either - NASA recently
| managed to run some test commands on Voyager 2. [0]
|
| [0] https://www.forbes.com/sites/startswithabang/2020/11/04
| /voya...
| mikepurvis wrote:
| For a lot of stuff there's redundancy too-- like rovers with
| six wheels but that can drive with any four, and the
| Curiosity and Perseverance missions having dual computers and
| dozens of cameras. I'm sure they run scenarios where
| significant chunks of the rover's systems fail and they
| figure out how to carry on anyway-- thinking in part here of
| the famous HGA issues on Galileo:
|
| https://en.wikipedia.org/wiki/Galileo_project#High_gain_ante.
| ..
| gibolt wrote:
| The planned mission length is generally very conservative,
| especially for missions which are not fuel limited (solar
| panels, etc).
|
| The cost of renewing operator contracts is much easier than
| getting funding for a new mission, and the cost of R&D,
| launch, and new operations.
| TedDoesntTalk wrote:
| Made in the USA and not offshored :)
| onethought wrote:
| Like that Mars orbiter that failed because it used imperial
| and metric units mixed together.
|
| Made in the USA
| ornitorrincos wrote:
| You mean, except the parts funded and built by the ESA,
| right? https://en.wikipedia.org/wiki/Hubble_Space_Telescope
| #Quest_f...
| Cogito wrote:
| A different mission, but Jake from We Martians did a really
| great twitter thread[0] about what goes in to the mission
| length. I'll summarise the thread here (mostly just quoting
| verbatim):
|
| Firstly, this is about why solar powered Mars missions
| (specifically InSight) do not have solar panel cleaning
| devices, but it touches on how missions can be extended and
| what thinking goes into that.
|
| Robotic missions to Mars are competed like any other; they have
| to "earn" their chunk of the budget by being effective science
| missions at effective prices. This causes a very normal tension
| between "do a lot" and "don't cost a lot".
|
| InSight in particular is part of the Discovery program at NASA,
| which technically has a cost cap of around $500M. Program
| managers thus do everything they can to reduce the cost without
| sacrificing science. You want to avoid taking instruments off,
| for example.
|
| One really effective way to reduce scope is to shorten
| missions. This has two big benefits:
|
| 1) Every year a mission doesn't operate is a year you don't
| have to pay salaries for those who operate it
|
| 2) Hardware on the spacecraft can be made cheaper if it doesn't
| have to last
|
| That second point is really critical.
|
| The testing program you have to put stuff through doesn't scale
| linearly. A mission that lasts twice as long costs _more_ than
| twice as much to test. It spirals fast.
|
| In InSight's case, they also saved money by reusing a
| spacecraft bus design from the Phoenix mission, which was also
| designed for a short mission - just 90 sols in fact.
|
| See the similarity?
|
| So all of these reasons (staying under cost cap, reducing
| operation cost, reducing testing costs and saving money by
| reusing spacecraft busses) combined to drive a decision that
| InSight's prime mission is just 1 Martian Year (about 2 Earth
| Years), which it completed in November.
|
| So the short answer to "why not add solar panel cleaning
| devices" is that they don't need them!
|
| By the time the dust takes down the spacecraft, it will have
| completed its mission. It's an element of disposability, though
| NASA probably wouldn't characterize it that way.
|
| Now, often the vehicles last longer than their prime mission.
| Spirit and Opportunity, for example, blew past their prime
| mission of 90 sols. All of NASA orbiters (ODY, MRO, MAVEN) have
| gone past their prime mission, too. Last November, InSight also
| surpassed its prime mission.
|
| When this happens, NASA reevaluates the vehicle's health & cost
| against further science it can do, and decides to either re-
| fund or end a mission.
|
| InSight got the funding, and so here we are making the best of
| that!
|
| NASA isn't scrambling to save a mission hampered by dust they
| forgot existed. They're doing their best to squeeze out more
| return on investment for the taxpayer on a spacecraft that has
| already completed its mission!
|
| 0: https://twitter.com/We_Martians/status/1360340875440578560
| Dylan16807 wrote:
| > So the short answer to "why not add solar panel cleaning
| devices" is that they don't need them!
|
| > By the time the dust takes down the spacecraft, it will
| have completed its mission. It's an element of disposability,
| though NASA probably wouldn't characterize it that way.
|
| I don't think that's a very compelling answer. The thing to
| ask, I guess, is whether they would have added them anyway if
| they were very cheap and lightweight.
|
| If yes then "it was a waste of resources for the designed
| mission" hits much closer to the real reason. But if no, it
| means the real reason is "bureaucratic maneuvering caused a
| longevity problem on purpose" which is really bad.
| JohnJamesRambo wrote:
| Sounds like they didn't do a good estimate of the lifespan.
| Grossly underestimating it to impress the general public is
| quite lame if you think about it. If you were 60 times off on
| your estimate that was a horrible estimate.
| _ph_ wrote:
| I wonder how expensive it would be to design an "affordable"
| space telescope which could be produced in a small series. The
| Falcon 9 should be able to launch a roughly hubble-sized
| telescope. So the launch costs would be a fraction of the shuttle
| costs back then. This means, more than one telescope could be
| launched and the telescope to be more designed to be
| "expendable". Which once again reduces costs a lot.
|
| I think one driver for the enormeous cost of a lot of space
| missions is the amount of overdesign happening as due to the high
| costs, failure is not an option. Just designing for 5 years and
| allowing for the early failure, costs should be so low that a
| failure is no longer a big issue.
|
| Also, if there is one basic platform, sending different
| telescopes with quite different sensor packages would be an
| option.
| JBorrow wrote:
| Also - we are currently launching another Hubble, called
| WFIRST. This was provided by a 3 letter US agency and required
| a mirror redesign. Launch costs are not a factor now, and
| weren't then either.
| _ph_ wrote:
| "Currently"? It is worked on and might launch after 2025.
| Also, it is different from Hubble, so not a direct
| replacmenet. But indeed, with a total budget of over 3
| billion dollars, launch costs are no longer the problem.
| Remains the question: why is it so expensive? Because it will
| have been worked on for more than 10 years and probably is
| over-engineered like hell, as you must not fail with a 3
| billion dollar telescope.
| JBorrow wrote:
| The reason it is so expensive is, as I said in my other
| comments - the instruments. These are one-off, heavily
| tested prototypes.
| _ph_ wrote:
| You are saying the magic word: prototypes. That explains
| the huge budgets, time and cost overruns. They certainly
| have an important place in science, because sciences
| often is about doing things the first time. But there is
| also a place for production runs. Because you are no
| longer just making prototypes but start to reuse the
| experiences and expenses.
|
| Hubble is 30 years old, and there isn't any direct
| replacement in sight at all. At latest now, with cheap
| launches and much improved technology, it is more than
| time to replace it and as it is more or less a direct
| replacement, use the scale of production. Don't build one
| telescope for 3 billion, build 10 at like 100-200 million
| each. If one ore more of them fail, so what?
| JBorrow wrote:
| Well the reason that we would build the one 3 bn
| telescope, rather than 10 100-200 m telescopes, is
| because they can tell you fundamentally different things
| about the Universe.
|
| In many ways, to move forward, we must go bigger with the
| tech, not wider. What you are essentially suggesting is a
| survey - we already have instruments and telescopes to do
| exactly that, with new ones coming online soon (see the
| LSST). Deep observations like Hubble was meant to do can
| actually be done better from the ground now (e.g. the
| VLT, ELT, etc.). As such, focus has shifted to those for
| optical observations.
|
| The community at large, however, has decided where it
| would like to spend its budget. That was on Webb for the
| IR wavebands, to study so-called 'high redshift' objects
| that Hubble struggles to see, and leave the more detailed
| imaging to those ground based observatories.
|
| Look, I would love another Hubble. That would be really
| useful! And that's why WFIRST exists. But an in-place
| replacement doesn't make sense. The tech on Hubble (not
| necessarily the mirror, but the _instruments_, the
| spectrographs, the interferometers) is really old. You
| can't take an off-the-shelf component, because it needs
| to be built to withstand space. So you need to create a
| one-off, 'prototype', space-hardened instrument. It is
| also not a case of worrying about them 'failing', but you
| also must worry about them slowly drifting out of a
| calibrated range. On the ground, you could fix the
| instrument, or re-calibrate it. That's not possible in
| space. That's not a 'random' style error, where we can
| get out of it by upping the number of them - they are
| systematic, so all 10 of your proposed telescopes would
| be ruined.
| jeffrallen wrote:
| A giant mirror is not expendable, and takes more than 5 years
| just to make. So until the astronomers tell the engineers, "hey
| no problem, we can do good science with little cheap mirrors",
| engineers are going to be stuck engineering the rest of the
| telescope around the economics of the mirror.
| tigershark wrote:
| You don't need a single giant mirror.
| https://en.m.wikipedia.org/wiki/Segmented_mirror Also the
| James Webb space telescope uses this technique:
| https://en.m.wikipedia.org/wiki/James_Webb_Space_Telescope
| _ph_ wrote:
| At about 2 meters of aperture, you can quite well still do a
| single mirror at reasonable costs. If the launch costs like
| 60 million, the telescope would realistically have a budget
| of 60-120 million for the platform. On that scale, a series
| of 2m mirrors should be affordable - you would of course
| order more than one mirror, so you have a reasonable supply.
|
| Considering that a single shuttle launch costet close to 1
| billion and the Webb telescope costs many billions, spending
| 1 billion on a set of 5 telescopes including launch costs
| sounds like a worthwhile program. Which could be scaled to
| more telescopes as long there is budget.
| JBorrow wrote:
| 2m is pittance for professional astronomy. Hubble may have
| a 2.4m mirror, but remember that is a 1980s era telescope.
|
| Current and future telescopes target 10-30m mirrors, purely
| for light capture reasons. We'd need to put something that
| big in space for it to be worthwhile.
| _ph_ wrote:
| No, even Hubble still delivers great contributions to
| science which are not quite matched by earthbound
| telescopes. Those win on aperture for sure, but Hubble is
| the only large telescope outside of the atmosphere. This
| gives access to wider wavelengths and removes all other
| atmospheric influences. That is the reason, the final
| passing of Hubble would be a huge loss, if not replaced.
|
| There are several aspects we could improve on the current
| situation: make "better" telescopes or make more
| telescope. Having only 1, soon 0 space-based telescopes
| is cutting it very thin. Having 5-10 would increase our
| research a lot as more things could be observed.
|
| Of course, eventually there will be a need for large
| space telescopes too, probably those will be enabled by
| Starship. But first we should use the currently available
| technology to make sure we don't fall back into the level
| of the 80ies when Hubble dies. And use modern technology
| to make this a "cheap" effort vs. the extremely expensive
| Hubble.
| est31 wrote:
| > Having only 1, soon 0 space-based telescopes is cutting
| it very thin. Having 5-10 would increase our research a
| lot as more things could be observed.
|
| Apparently they went the other way and instead of
| multiple Hubble-equivalent telescopes they build one
| which has equivalent sharpness of images but a much
| larger field of view, so can take images 100 times as
| large as what Hubble can.
|
| https://en.wikipedia.org/wiki/Nancy_Grace_Roman_Space_Tel
| esc...
| JBorrow wrote:
| AO improvements over the past decade have made ground-
| based astronomy provide better images, with large enough
| apertures, than Hubble.
|
| You are correct - the NIR is blocked by the atmosphere.
| That is why we are launching Webb. Optical, however, is
| very much now the domain of ground-based astronomy.
| tigershark wrote:
| James Webb space telescope is scheduled in 6 months and
| it has a 6.5m segmented mirror. A 2m telescope is pretty
| much useless, it doesn't have enough angular resolution
| and it's smaller than HST current mirror.
| okl wrote:
| Something like Astrosat or cheaper? At ~$25M it's rather cheap
| in relation to launch prices.
| https://en.wikipedia.org/wiki/Astrosat
|
| > Also, if there is one basic platform, sending different
| telescopes with quite different sensor packages would be an
| option.
|
| Satellites are usually designed around an integrator's
| platform, called "bus".
| https://en.wikipedia.org/wiki/Satellite_bus
| _ph_ wrote:
| I was more thinking of roughly hubble-sized telescopes, but
| as a program optimized for having several telescopes. Like
| spending 1 billion in total for a larger amount of
| telescopes, which can be easily replaced should one fail or
| new instruments are required.
| JBorrow wrote:
| A lot of the cost for space based missions is also in
| instrument design. When you make a telescope, you don't need to
| just design the mirror and the stuff that holds it up, and a
| camera with a series of filters. You need to design
| spectrographs and other complex systems that need to be "space-
| hardened" and extremely well tested. A "sensor package" doesn't
| really cut it. See for example this spectrograph:
|
| https://www.eso.org/public/images/ann13071c/
|
| Huge instruments like these that actually power today's science
| is another reason why ground based astronomy is required, and
| why we can't just move all observation to space if satellite
| clusters ruin the night sky.
| _ph_ wrote:
| Hubble is mainly a set of cameras attached to the telescope,
| it doesn't have anything comparable to what you linked. Yes,
| I am aware of all the advantages of ground based astronomy,
| which just got a huge boom by segmented mirrors basically
| removing the mirror size limit. The flexibility and costs of
| ground-based astronomy are superior for anything which can be
| done well from the ground. I have nowhere suggested to stop
| or defund ground based astronomy. We need ground based
| astronomy and space based one. So we need to come up with a
| replacement of Hubble, thats where my suggestions come from.
|
| And yes, I am aware of the challenges of space-going
| equipment. But if a system is designed for a life time of
| rather 5 than 30 years, things become a bit easier. Also, if
| you look at the camera equipment of Perseverance, a lot of it
| is off-shelve, only slightly enhanced for its intended
| purpose.
| SiempreViernes wrote:
| Uh, missions _are_ designed to last max five years, so you
| 're not gonna find any savings there. Maybe if you cut the
| high reliability requirements to five months you can skimp
| on some stuff, but I'm not sure that actually relaxes
| demands so much as that's still a lot of thermal cycles to
| maintain instrument alignment over.
| JBorrow wrote:
| As another commenter said, they are designed to work for
| 5ish years. That we have had Hubble so long is essentially
| a miracle. Same thing for the Mars rovers that limped on
| for years despite only being designed to last months.
|
| Also your claim about the instruments on Hubble is
| incorrect.
|
| See: https://www.nasa.gov/content/goddard/hubble-space-
| telescope-....
| NikolaeVarius wrote:
| As much as the Shuttle retirement was sorely needed, the
| inability to do servicing missions is very sad.
|
| I wonder what it would take to have a Commercial Orbital
| Servicing type system. Shove a Canadarm onto a X37B and fix the
| bastard
| devoutsalsa wrote:
| The shuttle was so expensive to launch, it might be cheaper to
| just launch a new Hubble.
| postingawayonhn wrote:
| You could probably launch a new one every year.
| orbital-decay wrote:
| EVAs are very expensive as well (compared to robotic
| servicing).
| avs733 wrote:
| The James Webb space telescope would disagree with that
| assessment.
| devoutsalsa wrote:
| Ha. The James Webb telescope is implementing a ton of new
| technologies and manufacturing techniques. Building a
| second one would presumably cost significantly less than
| the first, although I have no real basis for making that
| claim.
| avs733 wrote:
| Agree and same :)
| wereHamster wrote:
| The Hubble Space Telescope (HST) is basically a civilian
| version of the KH. And the National Reconnaissance Office
| (NRO) is launching one of those KH satellites every
| couple years. I bet the latest one (USA-290) has much
| better tech than Hubble and would make a good replacement
| for Hubble, with few modifications required.
|
| https://en.wikipedia.org/wiki/KH-11_Kennen.
| dylan604 wrote:
| Has the Hubble ever been used to image Earth?
| [deleted]
| icegreentea2 wrote:
| JWST is fundementally a different type of space telescope
| from Hubble, all of which contribute to its costing:
|
| * It's being deployed at L2 Lagrange point instead of LEO
| - so the launch costs are even higher.
|
| * HST had the insurance of knowing that repair was
| possible - JWST does not (both due to it's location and
| lack of capability) and so everything drags on even more
| to try to reduce risk
|
| * JWST is technically more complicated. The thermal
| management system needed, and entire origami unfolding
| mechanism alone would make it more complicated and
| expensive. This doesn't even start looking at the optics.
| skissane wrote:
| NASA's OSAM-1 (formerly known as Restore-L) mission is planned
| as a technology demonstrator of robotic servicing [0]. The
| target is the Landsat 7 satellite; but if the technology is
| successfully demonstrated by OSAM-1, it might be used for
| robotic servicing of space telescopes in the future.
|
| Originally targeted to launch in 2020, the project has
| encountered delays, and NASA is currently aiming for January
| 2025 as the launch date [1]
|
| [0] https://nexis.gsfc.nasa.gov/OSAM-1.html
|
| [1] https://sma.nasa.gov/docs/default-source/sma-disciplines-
| and... page 4
| caconym_ wrote:
| I don't know much about how the STS or ISS EVA airlocks are
| configured, but I wonder if you could do it with a slightly
| modified Crew Dragon docking nose-to-nose with another one. One
| acts as a fallback and home for the non-EVAing crew, and stays
| pressurized, while the other is used to stage the EVA and
| ultimately evacuated so that the astronaut(s) can leave via the
| hatch. You could launch one unmanned and have it wait in orbit
| for the other one, with crew.
|
| There's a fair amount of room in those trunk sections for any
| gear or parts they need to bring up, too. I guess my biggest
| concern would be whether the hatches are big enough for real
| EVA suits to get in and out easily, and whether the life
| support system can support multiple repressurizations without
| significant modification. They might also need to modify the
| docking adapters, which are "supposed" to be androgynous but
| IIRC actually aren't.
| Causality1 wrote:
| I think I'm going to genuinely cry the day they deorbit Hubble.
| Maybe it doesn't make financial sense but if there was ever an
| instrument that deserved to be retrieved and given a hallowed
| place in a museum, Hubble is it.
| gizmo686 wrote:
| The original plan was that it would be de-orbited aboard the
| Shuttle and put in a musuem.
|
| I'm not sure what the current plans are, but the last servicing
| mission installed the Soft Capture Mechanism, and the current
| understanding is that an uncontrolled re-entry would pose an
| unacceptable risk to human life. So, it seems like there is
| still a chance to put it in a musuem.
| GoOnThenDoTell wrote:
| Starship isn't too far away,
| williesleg wrote:
| Gotta get rid of the H1b's
|
| They're cheap but write shit code.
| herodotus wrote:
| This sounds more like hardware problems that need software work-
| arounds.
| tenderfault wrote:
| insert your dearest meme
|
| hubble: recovers after software glitch rustafarians:
| [deleted]
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