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This sounds to me like a new technology and a way of operating has come and we're trying to make it accommodate the old way of doing things. If we really have

This sounds to me like a new technology and a way of operating has come and we're trying to make it accommodate the old way of doing things. If we really have a way to launch thousands of satellites easily, can't we replace the terrestrial functionality with that? Let's launch hundreds of satellites observing near earth asteroids. If a private company can do it, governments definitely can

whatshisface 7y ago
That's a good point. SpaceX could be the key to launching a horde of new Hubbles. However that's not so likely in the short run because everything is going towards the JWST.
- mstipetic 7y ago
  JWST is a great project and a type of project we should strive for. I'm personally just annoyed why the conversation is so defensive and negative. I don't know much about astronomy, but from what I understand the Earth's atmosphere is hard to deal with, why aren't we talking more about what can be done with this new tech, and not how it makes current things more difficult
  - ceejayoz 7y ago
    It's the kind of telescope we should strive for, but definitely not the sort of project we should. It's more than a decade late and billions over budget.
  - ixf 7y ago
    Earth's atmosphere is annoying, yes, but for huge swathes of observational science it's not a deal-breaker. Not having massive telescopes on the ground where you can fiddle with your instrumentation and take advantage of apertures and construction techniques simply not possible in space _is_ a deal-breaker. The required precision for construction of telescopes is incredible, and doesn't translate to space well, especially once you start talking about apertures that even folded won't fit into even the largest Starship SpaceX is proposing. Ground-based astronomy is here to stay and with good reason. SpaceX needs to avoid or minimise the harms to these users of the night sky. There is another aspect of harm, too - the casual observer. The night sky is a precious resource and shared by all. Introducing huge constellations which in many parts of the world will be visible year-round (and in some quite heavily populated areas like northern Europe, even through the night at some times of year) is like building a huge mobile phone mast outside someone's window and expecting them not to complain, but on a much larger scale. Light pollution is a huge issue, and satellites can pollute just as well (if not more effectively) than ground based sources - it needs to be an ecological consideration of any launch.
    - mstipetic 7y ago
      I live in a very large city in Europe. I think the number of stars you can see is less than 20. Ground based pollution is horrible, I don't know how you can compare those two.
      - iudqnolq 7y ago
        Maybe because large telescopes aren't in very large cities.
        greglindahl 7y ago
        100 years ago, lots of them were.
        iudqnolq 7y ago
        Kind of. Some on mountains near cities, but even then light polution was an issue they had to mitigate. https://en.wikipedia.org/wiki/List_of_largest_optical_telescopes_in_the_20th_century?wprov=sfla1 https://en.wikipedia.org/wiki/List_of_largest_optical_telesc... In general, I'm fine with scientists needing to accommodate people more than they had to 100 years ago.
        greglindahl 7y ago
        That list of telescopes only goes back to 1932, and I studied astronomy at one of the institutions in question. As an example, why is this area named Observatory Hill? https://www.google.com/maps/place/Observatory+Hill,+Cambridge,+MA+02138,+USA/@42.3817392,-71.1344962,16z/data=!3m1!4b1!4m5!3m4!1s0x89e3776d1ec85c91:0xae23dbc6ed061fa6!8m2!3d42.382442!4d-71.1310717 https://www.google.com/maps/place/Observatory+Hill,+Cambridg... > In general, I'm fine with scie!tists needing to accommodate people more than they had to 100 years ago. Indeed, that's the majority opinion.
        iudqnolq 7y ago
  - greglindahl 7y ago
    I'm personally just annoyed that people are so happy to be annoyed at each other every time this discussion comes up, so there's that. Astronomers have been talking and acting for decades to take advantage of new technologies like orbital observatories.
Filligree 7y ago
Terrestrial telescopes are huge. Hubble is comparatively tiny, and launching a telescope the same size as the ones we use down here would be completely out of the question with any near-term launch capability.
- mstipetic 7y ago
  Well let's figure out a way to assemble them in space. Hubble is thirty years old, and is being used now as a reference. I don't understand all this negativity. Had we had this mindset, Hubble would not have been there
  - wpietri 7y ago
    Part of the negativity is who benefits from the problem versus who has to pay to fix it. If SpaceX were causing a problem for astronomers while also for free launching radically better space-based tools, it wouldn't be nearly as big a deal. But instead SpaceX hopes to pocket a lot of money, while the harms are falling on other people.
    - mrandish 7y ago
      > SpaceX hopes to pocket a lot of money True but to their credit SpaceX's launch prices are substantially lower than pre-existing options and they have been a leader in a step change in competitive launch options coming to market.
      - wpietri 7y ago
        So? I don't understand how that's material to my point.
    - avmich 7y ago
      > SpaceX hopes to pocket a lot of money and SpaceX customers hope to pocket a lot of use for that money. So taking that point literally - tiny astronomer's society is against the whole Earth load of Spacelink customers, and of course those customers' needs on average trump astronomers' ones. I'm exaggerating, of course.
cbanek 7y ago
So while it sounds good that we've fixed the launch industry and can launch everything cheaper, that we should only have space based telescopes, space telescopes are a very different game from ground based telescopes. First, as others have pointed out, is size. Ground based mirrors are very large, in the 10s of meters, and those mirrors are extremely heavy, like tons. You can't lift one of those mirrors up on one rocket, so you'll have to figure out some kind of in orbit construction. Not impossible, but we haven't assembled a lot of things in space, probably the biggest would be the ISS. But telescopes have tricky tolerances... Which leads me to the next issue: not only is it heavy, but telescopes are fragile. They have to be very carefully calibrated and put together. Launching something into space tends to be a very bumpy ride, and making something that can withstand that kind of vibration for launch, and then the thermal problems while in space would be certainly not trivial. But let's say you could build something and get it to work in orbit. Then it's still hard to service. Servicing the hubble to fix the optics was a very hard mission, and the hubble is relatively close to the earth. And that was when we had the shuttle, which we don't now. Cooling is very tricky for both telescopes and space. Since there's no air to radiate to, you can get big thermal gradients over the length of your craft and you have to be very careful how you point it. Same for the optics and the camera, you want to make sure they have as little thermal gradient as possible. Unlike a lot of commercial satellites, many scientific probes and telescopes are constantly refitted and reused. Ground based telescopes frequently reuse the same expensive (typically one-off) mirrors and put better cameras on them all the time. This is pretty hard to do in space. That being said, being in space does have a lot of advantages, the most obvious one being a lack of atmosphere to mess with your observations. But assembling large telescopes in space still isn't exactly easy. I think over time though, we will be heading to more space based telescopes as the cost comes down. But many slower moving telescope projects (mostly slow due to government funding) were started before Starlink was even announced.
- manicdee 7y ago
  The large telescope mirrors aren’t single parts even in terrestrial telescopes. We have to assemble and calibrate them on their isolated mountaintops, starting with the giant support structures intended for suspending the mirrors against the pull of gravity with minimum distortion regardless of orientation of the telescope. We then add active optics to compensate for atmospheric distortion, alter airline routes and city lighting to help improve conditions, and then pray for no clouds on the nights we want to observe. Constructing telescopes in space will become a reality within the next decade, while terrestrial telescopes currently in planning will be finding it harder and harder to navigate the mixture of light pollution, accessibility and indigenous rights. I expect there are terrestrial telescopes already in planning and even at early stages of construction which will never be finished. Between the ever-growing forest of red tape and the ever shrinking cost of building space telescopes in orbit, there will be an inflexion point where it makes sense to dedicate the remaining budget of a terrestrial telescope project to building its spaceborne replacement.

whatshisface 7y ago

That's a good point. SpaceX could be the key to launching a horde of new Hubbles. However that's not so likely in the short run because everything is going towards the JWST.

mstipetic 7y ago
JWST is a great project and a type of project we should strive for. I'm personally just annoyed why the conversation is so defensive and negative. I don't know much about astronomy, but from what I understand the Earth's atmosphere is hard to deal with, why aren't we talking more about what can be done with this new tech, and not how it makes current things more difficult
- ceejayoz 7y ago
  It's the kind of telescope we should strive for, but definitely not the sort of project we should. It's more than a decade late and billions over budget.
- ixf 7y ago
  Earth's atmosphere is annoying, yes, but for huge swathes of observational science it's not a deal-breaker. Not having massive telescopes on the ground where you can fiddle with your instrumentation and take advantage of apertures and construction techniques simply not possible in space _is_ a deal-breaker. The required precision for construction of telescopes is incredible, and doesn't translate to space well, especially once you start talking about apertures that even folded won't fit into even the largest Starship SpaceX is proposing. Ground-based astronomy is here to stay and with good reason. SpaceX needs to avoid or minimise the harms to these users of the night sky. There is another aspect of harm, too - the casual observer. The night sky is a precious resource and shared by all. Introducing huge constellations which in many parts of the world will be visible year-round (and in some quite heavily populated areas like northern Europe, even through the night at some times of year) is like building a huge mobile phone mast outside someone's window and expecting them not to complain, but on a much larger scale. Light pollution is a huge issue, and satellites can pollute just as well (if not more effectively) than ground based sources - it needs to be an ecological consideration of any launch.
  - mstipetic 7y ago
    I live in a very large city in Europe. I think the number of stars you can see is less than 20. Ground based pollution is horrible, I don't know how you can compare those two.
    - iudqnolq 7y ago
      Maybe because large telescopes aren't in very large cities.
      - greglindahl 7y ago
        100 years ago, lots of them were.
        iudqnolq 7y ago
        Kind of. Some on mountains near cities, but even then light polution was an issue they had to mitigate. https://en.wikipedia.org/wiki/List_of_largest_optical_telescopes_in_the_20th_century?wprov=sfla1 https://en.wikipedia.org/wiki/List_of_largest_optical_telesc... In general, I'm fine with scientists needing to accommodate people more than they had to 100 years ago.
        greglindahl 7y ago
        That list of telescopes only goes back to 1932, and I studied astronomy at one of the institutions in question. As an example, why is this area named Observatory Hill? https://www.google.com/maps/place/Observatory+Hill,+Cambridge,+MA+02138,+USA/@42.3817392,-71.1344962,16z/data=!3m1!4b1!4m5!3m4!1s0x89e3776d1ec85c91:0xae23dbc6ed061fa6!8m2!3d42.382442!4d-71.1310717 https://www.google.com/maps/place/Observatory+Hill,+Cambridg... > In general, I'm fine with scie!tists needing to accommodate people more than they had to 100 years ago. Indeed, that's the majority opinion.
        iudqnolq 7y ago
- greglindahl 7y ago
  I'm personally just annoyed that people are so happy to be annoyed at each other every time this discussion comes up, so there's that. Astronomers have been talking and acting for decades to take advantage of new technologies like orbital observatories.

Filligree 7y ago

Terrestrial telescopes are huge. Hubble is comparatively tiny, and launching a telescope the same size as the ones we use down here would be completely out of the question with any near-term launch capability.

mstipetic 7y ago
Well let's figure out a way to assemble them in space. Hubble is thirty years old, and is being used now as a reference. I don't understand all this negativity. Had we had this mindset, Hubble would not have been there
- wpietri 7y ago
  Part of the negativity is who benefits from the problem versus who has to pay to fix it. If SpaceX were causing a problem for astronomers while also for free launching radically better space-based tools, it wouldn't be nearly as big a deal. But instead SpaceX hopes to pocket a lot of money, while the harms are falling on other people.
  - mrandish 7y ago
    > SpaceX hopes to pocket a lot of money True but to their credit SpaceX's launch prices are substantially lower than pre-existing options and they have been a leader in a step change in competitive launch options coming to market.
    - wpietri 7y ago
      So? I don't understand how that's material to my point.
  - avmich 7y ago
    > SpaceX hopes to pocket a lot of money and SpaceX customers hope to pocket a lot of use for that money. So taking that point literally - tiny astronomer's society is against the whole Earth load of Spacelink customers, and of course those customers' needs on average trump astronomers' ones. I'm exaggerating, of course.

cbanek 7y ago

So while it sounds good that we've fixed the launch industry and can launch everything cheaper, that we should only have space based telescopes, space telescopes are a very different game from ground based telescopes. First, as others have pointed out, is size. Ground based mirrors are very large, in the 10s of meters, and those mirrors are extremely heavy, like tons. You can't lift one of those mirrors up on one rocket, so you'll have to figure out some kind of in orbit construction. Not impossible, but we haven't assembled a lot of things in space, probably the biggest would be the ISS. But telescopes have tricky tolerances... Which leads me to the next issue: not only is it heavy, but telescopes are fragile. They have to be very carefully calibrated and put together. Launching something into space tends to be a very bumpy ride, and making something that can withstand that kind of vibration for launch, and then the thermal problems while in space would be certainly not trivial. But let's say you could build something and get it to work in orbit. Then it's still hard to service. Servicing the hubble to fix the optics was a very hard mission, and the hubble is relatively close to the earth. And that was when we had the shuttle, which we don't now. Cooling is very tricky for both telescopes and space. Since there's no air to radiate to, you can get big thermal gradients over the length of your craft and you have to be very careful how you point it. Same for the optics and the camera, you want to make sure they have as little thermal gradient as possible. Unlike a lot of commercial satellites, many scientific probes and telescopes are constantly refitted and reused. Ground based telescopes frequently reuse the same expensive (typically one-off) mirrors and put better cameras on them all the time. This is pretty hard to do in space. That being said, being in space does have a lot of advantages, the most obvious one being a lack of atmosphere to mess with your observations. But assembling large telescopes in space still isn't exactly easy. I think over time though, we will be heading to more space based telescopes as the cost comes down. But many slower moving telescope projects (mostly slow due to government funding) were started before Starlink was even announced.

manicdee 7y ago
The large telescope mirrors aren’t single parts even in terrestrial telescopes. We have to assemble and calibrate them on their isolated mountaintops, starting with the giant support structures intended for suspending the mirrors against the pull of gravity with minimum distortion regardless of orientation of the telescope. We then add active optics to compensate for atmospheric distortion, alter airline routes and city lighting to help improve conditions, and then pray for no clouds on the nights we want to observe. Constructing telescopes in space will become a reality within the next decade, while terrestrial telescopes currently in planning will be finding it harder and harder to navigate the mixture of light pollution, accessibility and indigenous rights. I expect there are terrestrial telescopes already in planning and even at early stages of construction which will never be finished. Between the ever-growing forest of red tape and the ever shrinking cost of building space telescopes in orbit, there will be an inflexion point where it makes sense to dedicate the remaining budget of a terrestrial telescope project to building its spaceborne replacement.