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How would you have gotten even one HST sized telescope into orbit without a manned mission? Do you know what life span of a Hubble would have been if it were no

How would you have gotten even one HST sized telescope into orbit without a manned mission? Do you know what life span of a Hubble would have been if it were not serviceable? Your approach would have cost more, not less. More manned fights, more time consuming, expensive design and construction. Believe it or not, they thought about this stuff.

Retric 12y ago
How would you have gotten even one HST sized telescope into orbit without a manned mission? How do we get similar sized spy satellites into orbit without people? http://www.space.com/16000-spy-satellites-space-telescopes-nasa.html http://www.space.com/16000-spy-satellites-space-telescopes-n... As to lifetime, we don't need a 30 year lifespan. If you average 6 years * 5 satellites you get 30 years and I suspect we could easily average 8-10 years. As to thinking about this stuff. Clearly, but Hubble was specifically designed to make the Shuttle seem more relevant. Just about all of the major decisions where made for political not technical reasons.
- CWuestefeld 12y ago
  Hubble was specifically designed to make the Shuttle seem more relevant. It flows both ways. Hubble was designed to take advantage of the planned capabilities of the shuttle, but also, the Hubble was an important use case in setting shuttle requirements. And as I pointed out elsewhere in this thread, the shuttle dropped the ball on many of these, both functionally and in terms of delivery dates.
- damoncali 12y ago
  Every decision at NASA is political - it's a government entity (look up Triana - that's another one I worked on. It's laughably ridiculous). But you're grossly oversimplifying. There isn't a prayer in heaven that would keep Hubble alive for 10 years on its own. Hubble made sense as a shuttle payload for a lot of reasons. I'm sure someone could have cooked up alternatives, but the one we got obviously did some good.
  - Retric 12y ago
    As government programs I think both Hubble and the Space shuttle where significantly better than average. Realistically redundancy is the first thing that gets cut at budget time etc etc. Still, what makes you think building a Hubble equivalent that would last 8-10 years is outside the realm of the reasonable when Hubble is expected to last 7 or 8 years after the last servicing mission.
    - scott_s 12y ago
      I get what you're saying, and I agree it's possible. But I think the position you're taking is too strong, in that you seemed to have accepted that it must be true. I think that what you're saying is reasonable, possible, and could be the case. But I don't think you have enough information to claim so strongly that it is certainly true.
      - Retric 12y ago
        That’s probably the most reasonable statement I have ever seen on the internet. I try to judge past decisions in context not just based on what worked. At the time we did not know that each of those servicing missions would work or even if the initial launch would work. Though, clearly one path worked and the Servicing missions where incredibly valuable experience. But, they could have also cost a shuttle and several astronauts lives. Granted, the odds of multiple telescopes being sent up in a fairly short time period is tiny so it's only reasonable on a technical level. In the end I think the Hubble program is completely justifiable, but that justification needs to be about more than just a quest for pretty false color pictures or worse an example of the sunk cost fallacy.
        damoncali 12y ago
        You bring up an interesting point regarding astronaut safety. It's interesting to me because I have the polar opposite opinion. This will sound cold, but astronauts are basically expendable. We can expect a small percentage of them to die. Much like in the military, the mission takes priority over safety, which comes second. Given that we have no shortage of astronauts willing to accept that, and that we do put a ton of effort into their safety, I have no qualms whatsoever pushing the limits of what is possible. I've met a lot of astronauts - I don't recall meeting a single one who didn't fully understand how dangerous the work is. It's not for everyone. Personally, I think they're nuts to take that risk for what amounts to floating around in a stinky can for a few days, punctuated by brief stints of mechanic duty. This always struck me as a major disconnect between the brass at NASA and the engineers. The higher up the chain you went, the more concerned with safety, politics, and perception they were, and the less concerned with what I would say the true goals of the space program are - the actual exploration of space.
dalke 12y ago
The James Webb Space Telescope is ~5x larger than HST, and it will be launched on an Ariane 5 rocket, with a lifespan goal of 10 years and no opportunity for repair or replenishment. You should ask them how they can deploy such a large telescope without a crew. Or ask the NRO how they launch a KH-11 spy satellites, which is the same size as Hubble, and launched on a Delta IV Heavy rocket. Hubble was built assuming shuttle launches would be cheap. It wasn't.
- damoncali 12y ago
  Fair point on launching big stuff - I suppose that a Hubble derivative could have been designed to work with one of the bigger rockets. But a hoped for lifespan of 10 years is not even close to what you get out of Hubble servicing missions. The ability to improve and repair a working telescope is not without value. Things go wrong all the time with these instruments. No serviceability = higher risk. You can indeed adapt your designs for unmanned launches and get a good life span out of them, but there are significant tradeoffs to doing so that impact the mission. Further, there is value in manned missions just because. How are we to gain experience operating in space without sending people there?
  - dalke 12y ago
    Yes, Hubble has been around for 25 years. There's a question of cost though. Each repair job costs about $1 billion and has a ~1% chance of killing the crew. (When Hubble was designed, it was thought that the Shuttle would be cheaper and safer than it was.) If we could build an launch a Hubble for $1 billion, then it's obviously cheaper to send up a new one than repair it each time. If it lasts for 10 years, then if the unit cost to launch were under $3 billion then it would still be cheaper to launch a new one than fix one in-place. So how much did Hubble cost? Wikipedia says $2.5 billion to construct. http://www.nasa.gov/pdf/499224main_JWST-ICRP_Report-FINAL.pdf http://www.nasa.gov/pdf/499224main_JWST-ICRP_Report-FINAL.pd... says "Again, to put this in context, HST, which was a much less complex mission [than Webb], had a total cost-to-launch of approximately $5 billion in current dollars. Hubble’s LCC was approximately double this because of servicing costs over 20 years." (Those are 2010 dollars.) Hubble also had huge cost overruns. The KH-11 has an estimated unit cost, including launch, of US$2.26 to 3.16 billion in 2015 dollars, says http://en.wikipedia.org/wiki/KH-11_Kennan#Cost http://en.wikipedia.org/wiki/KH-11_Kennan#Cost . We've built several of those, which I assume helps reduce the per-unit costs. If we could get the Hubble-like unit cost, including launch, down to $2.5 million, and with a 10 year life time, then we could launch 4 for what we've spent on Hubble, and lower risk through redundancy. "No serviceability" = "cheaper design" = "can launch more" = "lower risk". Again, this is based on the experience since the 1970s that manned missions are expensive and risky. Regarding just because - your original question was "How would you have gotten even one HST sized telescope into orbit without a manned mission?" That's all I'm addressing.

Retric 12y ago

How would you have gotten even one HST sized telescope into orbit without a manned mission? How do we get similar sized spy satellites into orbit without people? http://www.space.com/16000-spy-satellites-space-telescopes-nasa.html http://www.space.com/16000-spy-satellites-space-telescopes-n... As to lifetime, we don't need a 30 year lifespan. If you average 6 years * 5 satellites you get 30 years and I suspect we could easily average 8-10 years. As to thinking about this stuff. Clearly, but Hubble was specifically designed to make the Shuttle seem more relevant. Just about all of the major decisions where made for political not technical reasons.

CWuestefeld 12y ago
Hubble was specifically designed to make the Shuttle seem more relevant. It flows both ways. Hubble was designed to take advantage of the planned capabilities of the shuttle, but also, the Hubble was an important use case in setting shuttle requirements. And as I pointed out elsewhere in this thread, the shuttle dropped the ball on many of these, both functionally and in terms of delivery dates.
damoncali 12y ago
Every decision at NASA is political - it's a government entity (look up Triana - that's another one I worked on. It's laughably ridiculous). But you're grossly oversimplifying. There isn't a prayer in heaven that would keep Hubble alive for 10 years on its own. Hubble made sense as a shuttle payload for a lot of reasons. I'm sure someone could have cooked up alternatives, but the one we got obviously did some good.
- Retric 12y ago
  As government programs I think both Hubble and the Space shuttle where significantly better than average. Realistically redundancy is the first thing that gets cut at budget time etc etc. Still, what makes you think building a Hubble equivalent that would last 8-10 years is outside the realm of the reasonable when Hubble is expected to last 7 or 8 years after the last servicing mission.
  - scott_s 12y ago
    I get what you're saying, and I agree it's possible. But I think the position you're taking is too strong, in that you seemed to have accepted that it must be true. I think that what you're saying is reasonable, possible, and could be the case. But I don't think you have enough information to claim so strongly that it is certainly true.
    - Retric 12y ago
      That’s probably the most reasonable statement I have ever seen on the internet. I try to judge past decisions in context not just based on what worked. At the time we did not know that each of those servicing missions would work or even if the initial launch would work. Though, clearly one path worked and the Servicing missions where incredibly valuable experience. But, they could have also cost a shuttle and several astronauts lives. Granted, the odds of multiple telescopes being sent up in a fairly short time period is tiny so it's only reasonable on a technical level. In the end I think the Hubble program is completely justifiable, but that justification needs to be about more than just a quest for pretty false color pictures or worse an example of the sunk cost fallacy.
      - damoncali 12y ago
        You bring up an interesting point regarding astronaut safety. It's interesting to me because I have the polar opposite opinion. This will sound cold, but astronauts are basically expendable. We can expect a small percentage of them to die. Much like in the military, the mission takes priority over safety, which comes second. Given that we have no shortage of astronauts willing to accept that, and that we do put a ton of effort into their safety, I have no qualms whatsoever pushing the limits of what is possible. I've met a lot of astronauts - I don't recall meeting a single one who didn't fully understand how dangerous the work is. It's not for everyone. Personally, I think they're nuts to take that risk for what amounts to floating around in a stinky can for a few days, punctuated by brief stints of mechanic duty. This always struck me as a major disconnect between the brass at NASA and the engineers. The higher up the chain you went, the more concerned with safety, politics, and perception they were, and the less concerned with what I would say the true goals of the space program are - the actual exploration of space.

dalke 12y ago

The James Webb Space Telescope is ~5x larger than HST, and it will be launched on an Ariane 5 rocket, with a lifespan goal of 10 years and no opportunity for repair or replenishment. You should ask them how they can deploy such a large telescope without a crew. Or ask the NRO how they launch a KH-11 spy satellites, which is the same size as Hubble, and launched on a Delta IV Heavy rocket. Hubble was built assuming shuttle launches would be cheap. It wasn't.

damoncali 12y ago
Fair point on launching big stuff - I suppose that a Hubble derivative could have been designed to work with one of the bigger rockets. But a hoped for lifespan of 10 years is not even close to what you get out of Hubble servicing missions. The ability to improve and repair a working telescope is not without value. Things go wrong all the time with these instruments. No serviceability = higher risk. You can indeed adapt your designs for unmanned launches and get a good life span out of them, but there are significant tradeoffs to doing so that impact the mission. Further, there is value in manned missions just because. How are we to gain experience operating in space without sending people there?
- dalke 12y ago
  Yes, Hubble has been around for 25 years. There's a question of cost though. Each repair job costs about $1 billion and has a ~1% chance of killing the crew. (When Hubble was designed, it was thought that the Shuttle would be cheaper and safer than it was.) If we could build an launch a Hubble for $1 billion, then it's obviously cheaper to send up a new one than repair it each time. If it lasts for 10 years, then if the unit cost to launch were under $3 billion then it would still be cheaper to launch a new one than fix one in-place. So how much did Hubble cost? Wikipedia says $2.5 billion to construct. http://www.nasa.gov/pdf/499224main_JWST-ICRP_Report-FINAL.pdf http://www.nasa.gov/pdf/499224main_JWST-ICRP_Report-FINAL.pd... says "Again, to put this in context, HST, which was a much less complex mission [than Webb], had a total cost-to-launch of approximately $5 billion in current dollars. Hubble’s LCC was approximately double this because of servicing costs over 20 years." (Those are 2010 dollars.) Hubble also had huge cost overruns. The KH-11 has an estimated unit cost, including launch, of US$2.26 to 3.16 billion in 2015 dollars, says http://en.wikipedia.org/wiki/KH-11_Kennan#Cost http://en.wikipedia.org/wiki/KH-11_Kennan#Cost . We've built several of those, which I assume helps reduce the per-unit costs. If we could get the Hubble-like unit cost, including launch, down to $2.5 million, and with a 10 year life time, then we could launch 4 for what we've spent on Hubble, and lower risk through redundancy. "No serviceability" = "cheaper design" = "can launch more" = "lower risk". Again, this is based on the experience since the 1970s that manned missions are expensive and risky. Regarding just because - your original question was "How would you have gotten even one HST sized telescope into orbit without a manned mission?" That's all I'm addressing.