7 ms·

Hubble Space Telescope is back online after software glitch

174 points by wglb 6y ago

jeffgreco 6y ago
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.
- callesgg 6y ago
  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.
  - sephamorr 6y ago
    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 6y ago
    > 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.
  - ghaff 6y ago
    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.
- supernova87a 6y ago
  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.
- ISL 6y ago
  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.
  - mikepurvis 6y ago
    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_antenna_problem https://en.wikipedia.org/wiki/Galileo_project#High_gain_ante...
  - qbasic_forever 6y ago
    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 6y ago
      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/voyager-2-phones-home-and-nasa-still-receives-the-call/ https://www.forbes.com/sites/startswithabang/2020/11/04/voya...
  - gibolt 6y ago
    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.
- throwawayboise 6y ago
  Except for that part where it was useless after it was launched, until an expensive and unplanned repair mission was undertaken.
  - qbasic_forever 6y ago
    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.
- JohnJamesRambo 6y ago
  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.
- Cogito 6y ago
  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 https://twitter.com/We_Martians/status/1360340875440578560
NikolaeVarius 6y ago
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
- caconym_ 6y ago
  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.
- skissane 6y ago
  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 https://nexis.gsfc.nasa.gov/OSAM-1.html [1] https://sma.nasa.gov/docs/default-source/sma-disciplines-and-programs/smsr/smsr-intergrated-master-schedule_24feb2020aab4a269d2a865b9a1a0ff0f003ca228.pdf https://sma.nasa.gov/docs/default-source/sma-disciplines-and... page 4
- devoutsalsa 6y ago
  The shuttle was so expensive to launch, it might be cheaper to just launch a new Hubble.
deleted 6y ago
[deleted]
Causality1 6y ago
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 6y ago
  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 6y ago
    Starship isn’t too far away,
_ph_ 6y ago
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 6y ago
  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/ 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_ 6y ago
    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.
tenderfault 6y ago
insert your dearest meme hubble: recovers after software glitch rustafarians:
williesleg 6y ago
Gotta get rid of the H1b's They're cheap but write shit code.
herodotus 6y ago
This sounds more like hardware problems that need software work-arounds.

174 points by wglb 6y ago

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.

callesgg 6y ago
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.
- sephamorr 6y ago
  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 6y ago
  > 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.
- ghaff 6y ago
  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.
supernova87a 6y ago
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.
ISL 6y ago
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.
- mikepurvis 6y ago
  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_antenna_problem https://en.wikipedia.org/wiki/Galileo_project#High_gain_ante...
- qbasic_forever 6y ago
  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 6y ago
    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/voyager-2-phones-home-and-nasa-still-receives-the-call/ https://www.forbes.com/sites/startswithabang/2020/11/04/voya...
- gibolt 6y ago
  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.
throwawayboise 6y ago
Except for that part where it was useless after it was launched, until an expensive and unplanned repair mission was undertaken.
- qbasic_forever 6y ago
  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.
JohnJamesRambo 6y ago
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.
Cogito 6y ago
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 https://twitter.com/We_Martians/status/1360340875440578560

NikolaeVarius 6y ago

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

caconym_ 6y ago
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.
skissane 6y ago
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 https://nexis.gsfc.nasa.gov/OSAM-1.html [1] https://sma.nasa.gov/docs/default-source/sma-disciplines-and-programs/smsr/smsr-intergrated-master-schedule_24feb2020aab4a269d2a865b9a1a0ff0f003ca228.pdf https://sma.nasa.gov/docs/default-source/sma-disciplines-and... page 4
devoutsalsa 6y ago
The shuttle was so expensive to launch, it might be cheaper to just launch a new Hubble.

deleted 6y ago

[deleted]

Causality1 6y ago

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 6y ago
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 6y ago
  Starship isn’t too far away,

_ph_ 6y ago

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 6y ago
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/ 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_ 6y ago
  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.

tenderfault 6y ago

insert your dearest meme hubble: recovers after software glitch rustafarians:

williesleg 6y ago

Gotta get rid of the H1b's They're cheap but write shit code.

herodotus 6y ago

This sounds more like hardware problems that need software work-arounds.