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NASA didn’t design for serviceability, but rather the NRO. There’s an old photo showing a Hubble mirror being ground by a technician in 1979. It’s a cute how-t

by xattt 2y ago

NASA didn’t design for serviceability, but rather the NRO. There’s an old photo showing a Hubble mirror being ground by a technician in 1979. It’s a cute how-the-sausage-is-made photo, until you think about the timelines when Hubble was donated and realize it’s a photo of top secret work being done. (1) https://en.m.wikipedia.org/wiki/File:Hubble_mirror_polishing.jpg https://en.m.wikipedia.org/wiki/File:Hubble_mirror_polishing...

Zarkonnen 2y ago
Quite, let's not bury the fact that the HST is a modified KH-11 spy satellite aimed the other way.
- lizknope 2y ago
  https://en.wikipedia.org/wiki/KH-11_KENNEN https://en.wikipedia.org/wiki/KH-11_KENNEN We don't know how much of it is the same but the mirror is very similar. > KH-11s are believed to resemble the Hubble Space Telescope in size and shape, as they were shipped in similar containers. Their length is believed to be 19.5 meters, with a diameter of up to 3 meters (120 in).[5][23] A NASA history of the Hubble,[24] in discussing the reasons for switching from a 3-meter main mirror to a 2.4-meter (94 in) design, states: "In addition, changing to a 2.4-meter mirror would lessen fabrication costs by using manufacturing technologies developed for military spy satellites". > In January 2011, NRO donated to NASA two space Optical Telescope Assemblies with 2.4 meters (94 in) diameter primary mirrors,[53][54][55][56] similar in size to the Hubble Space Telescope, yet with steerable secondary mirrors and shorter focal length (resulting in a wider field of view). These were initially believed to be KH-11 series "extra hardware", but were later attributed to the cancelled Future Imaging Architecture program.[57] The mirrors are to be used by NASA as the primary and spare for the Roman Space Telescope.
- _djo_ 2y ago
  That's not accurate. You're thinking of the Nancy Grace Roman Space Telescope [0] [0] https://en.wikipedia.org/wiki/2012_National_Reconnaissance_Office_space_telescope_donation_to_NASA https://en.wikipedia.org/wiki/2012_National_Reconnaissance_O...
  - chankstein38 2y ago
    As someone who doesn't have a lot of knowledge here, I appreciate your corrections and sources!
- akira2501 2y ago
  And the shuttle was designed to launch and recover DoD payloads. There's a lot of "military synergy" in the early space program. No one else was interested in paying.
- adastra22 2y ago
  It is not that simple. Hubble was developed in the open by nasa civil servants who did not have access to KH-11 design. The non-optical systems are entirely different between the two platforms. Some of the contractors were shared however, and may or may not have reused IP and tooling. A lot of it is convergent evolution though. The size of the space shuttle payload bay was set by the DOD to be large enough to carry or return a KH 11 spy satellite, even though it was never used for that purpose AFAIK. The size of the Hubble was obviously the max size they could fit in the space shuttle. So they both ended up being identically sized optical telescopes, and it’s not surprising that similar design requirements end up making similar devices.
  - Kon-Peki 2y ago
    My grandfather worked on some aspect of the Hubble design (I was young; I think the timing would have put him at Lockheed M&S in Sunnyvale at that time). He never said anything about his work on it being classified. He used to say "when I retired, the stack of NDAs was this tall" and show his index finger and thumb being about 3 inches apart. He was a very serious guy and would never talk about anything he shouldn't have. So yes, I believe the fact that he was willing to talk about Hubble meant it was done in the open. And also, he never expressed any sort of amazement that it was still up there, working. Why wouldn't it be?
    - adastra22 2y ago
      Hubble was done in the open, this is an established fact. Since some of the contractors companies were the same, though usually not the same employees, it’s an open question we plebs may never know as to whether some aspects of KH-11 were declassified and shared with the workers doing Hubble. But if we’re talking anecdotes, I worked at Lockheed as well, though not back then, and one of the stories I heard was that when the Hubble was in Sunnyvale to get tested in the vacuum chamber, one of the KH-11 workers stopped by to check it out. He spotted something that was a unique invention for the KH spy satellites and alerted the government. It took a LOT of paperwork to show that nope, it was just accidental convergent design. It was a tricky thing to sort out, but really the only way of solving that problem given the identical requirements.
_djo_ 2y ago
You're confusing two different programmes. Hubble was a programme dating back to the 1960s as the Large Space Telescope (LST)[0], but first given the full go ahead in 1978. It was designed and developed in the open, with the Marshall Space Flight Center as the main design location. The donated NRO satellites were the two donated in 2012[1] and were reportedly KH-11s. Only one of those is being developed into a space telescope, the Nancy Grace Roman Space Telescope. [2] [0] https://science.nasa.gov/mission/hubble/overview/the-history-of-hubble/ https://science.nasa.gov/mission/hubble/overview/the-history... [1] https://en.wikipedia.org/wiki/2012_National_Reconnaissance_Office_space_telescope_donation_to_NASA https://en.wikipedia.org/wiki/2012_National_Reconnaissance_O... [2] https://en.wikipedia.org/wiki/Nancy_Grace_Roman_Space_Telescope https://en.wikipedia.org/wiki/Nancy_Grace_Roman_Space_Telesc...
- kevin_thibedeau 2y ago
  It's also worth adding that the Hubble mirror was made by Perkin-Elmer with a backup made by Kodak. The Kodak mirror is the one with "heritage".
  - _djo_ 2y ago
    Technically both Perkin-Elmer and Kodak had heritage, as Perkin-Elmer had made mirrors for the KH-9, but Kodak was making the KH-11 mirrors. NASA initially considered a 3m main mirror for the HST, but opted for a 2.4m mirror especially to take advantage of the existing industrial base for 2.4m mirrors for the KH-11. As it was a proven industrial process that derisked the project and reduced cost compared to a 3m mirror.
    - adastra22 2y ago
      And ironically was the part that failed.
    - jcrawfordor 2y ago
      Producing these large mirrors is a very specialized industry, the projects are extremely expensive, and the timelines are long. Things tend to get passed around between programs, sometimes for reasons as simple as a mirror having been completed after its original customer cancelled it. So it's hard to establish direct causality sometimes, especially since some of the "synergy" between projects was leveraged by the contractors to complete similar tasks without necessarily having direct interaction between the parent projects. It's sort of like air surveillance radar. There's only a few companies that make them, the clients are civilian or military, but the economics mean that both the vendors and customers are incentivized to align the civilian and military systems as much as possible (including through shared-use agreements) in order to make the design and purchasing more economical. Thus the civilian designs are all modifications of the military designs and the military designs are all modifications of the civilian designs, they have essentially evolved in parallel. I used to work on the MRO 2.4 meter telescope (at a small university observatory). Its main mirror was a Hubble design competition prototype that was transferred to the Air Force for intelligence use after the design wasn't selected. The Air Force kept it in storage for a long time and then provided it as part of their incentives to build the 2.4 meter with dual scientific and military applications. A lot of large mirrors used in astronomy and intelligence have stories like this. There's a number of 2.4 meter mirrors out there and pretty much all of them were made for either Hubble, KH-11, or as a shot at both. Radio astronomy is no exception, there's a reason I bring up radar. Most radio astronomy observatories early on incorporated microwave electronics that were designed for weapons targeting radar---sometimes extremely directly, with military radar prototypes having been "looted for parts" by the astronomy commmunity after they were retired. Microwave electronics were very costly to design at the time and it saved everyone a lot of money to reuse everything.
treyd 2y ago
I have a theory that the reason they screwed up the optics initially was because they had to adapt the design from the spy satellite design.
- downrightmike 2y ago
  No, the identically made mirror that kodak made in parallel was perfectly fine. the first mirror's manufacturer made a mistake
reneherse 2y ago
Indeed the institutional/industrial context of that photo is extremely intriguing and the stories I've heard could fill the pages of a Tom Clancy novel. The level of secrecy at the facility was so rigorous and taken so much to heart that even years after various NRO programs were declassified (decades after program conclusion), the retired civilian personnel I've had the privilege to know were reluctant to speak openly. I will see if I can persuade one retired engineer I know to join this discussion!

by xattt 2y ago

Zarkonnen 2y ago

Quite, let's not bury the fact that the HST is a modified KH-11 spy satellite aimed the other way.

lizknope 2y ago
https://en.wikipedia.org/wiki/KH-11_KENNEN https://en.wikipedia.org/wiki/KH-11_KENNEN We don't know how much of it is the same but the mirror is very similar. > KH-11s are believed to resemble the Hubble Space Telescope in size and shape, as they were shipped in similar containers. Their length is believed to be 19.5 meters, with a diameter of up to 3 meters (120 in).[5][23] A NASA history of the Hubble,[24] in discussing the reasons for switching from a 3-meter main mirror to a 2.4-meter (94 in) design, states: "In addition, changing to a 2.4-meter mirror would lessen fabrication costs by using manufacturing technologies developed for military spy satellites". > In January 2011, NRO donated to NASA two space Optical Telescope Assemblies with 2.4 meters (94 in) diameter primary mirrors,[53][54][55][56] similar in size to the Hubble Space Telescope, yet with steerable secondary mirrors and shorter focal length (resulting in a wider field of view). These were initially believed to be KH-11 series "extra hardware", but were later attributed to the cancelled Future Imaging Architecture program.[57] The mirrors are to be used by NASA as the primary and spare for the Roman Space Telescope.
_djo_ 2y ago
That's not accurate. You're thinking of the Nancy Grace Roman Space Telescope [0] [0] https://en.wikipedia.org/wiki/2012_National_Reconnaissance_Office_space_telescope_donation_to_NASA https://en.wikipedia.org/wiki/2012_National_Reconnaissance_O...
- chankstein38 2y ago
  As someone who doesn't have a lot of knowledge here, I appreciate your corrections and sources!
akira2501 2y ago
And the shuttle was designed to launch and recover DoD payloads. There's a lot of "military synergy" in the early space program. No one else was interested in paying.
adastra22 2y ago
It is not that simple. Hubble was developed in the open by nasa civil servants who did not have access to KH-11 design. The non-optical systems are entirely different between the two platforms. Some of the contractors were shared however, and may or may not have reused IP and tooling. A lot of it is convergent evolution though. The size of the space shuttle payload bay was set by the DOD to be large enough to carry or return a KH 11 spy satellite, even though it was never used for that purpose AFAIK. The size of the Hubble was obviously the max size they could fit in the space shuttle. So they both ended up being identically sized optical telescopes, and it’s not surprising that similar design requirements end up making similar devices.
- Kon-Peki 2y ago
  My grandfather worked on some aspect of the Hubble design (I was young; I think the timing would have put him at Lockheed M&S in Sunnyvale at that time). He never said anything about his work on it being classified. He used to say "when I retired, the stack of NDAs was this tall" and show his index finger and thumb being about 3 inches apart. He was a very serious guy and would never talk about anything he shouldn't have. So yes, I believe the fact that he was willing to talk about Hubble meant it was done in the open. And also, he never expressed any sort of amazement that it was still up there, working. Why wouldn't it be?
  - adastra22 2y ago
    Hubble was done in the open, this is an established fact. Since some of the contractors companies were the same, though usually not the same employees, it’s an open question we plebs may never know as to whether some aspects of KH-11 were declassified and shared with the workers doing Hubble. But if we’re talking anecdotes, I worked at Lockheed as well, though not back then, and one of the stories I heard was that when the Hubble was in Sunnyvale to get tested in the vacuum chamber, one of the KH-11 workers stopped by to check it out. He spotted something that was a unique invention for the KH spy satellites and alerted the government. It took a LOT of paperwork to show that nope, it was just accidental convergent design. It was a tricky thing to sort out, but really the only way of solving that problem given the identical requirements.

_djo_ 2y ago

You're confusing two different programmes. Hubble was a programme dating back to the 1960s as the Large Space Telescope (LST)[0], but first given the full go ahead in 1978. It was designed and developed in the open, with the Marshall Space Flight Center as the main design location. The donated NRO satellites were the two donated in 2012[1] and were reportedly KH-11s. Only one of those is being developed into a space telescope, the Nancy Grace Roman Space Telescope. [2] [0] https://science.nasa.gov/mission/hubble/overview/the-history-of-hubble/ https://science.nasa.gov/mission/hubble/overview/the-history... [1] https://en.wikipedia.org/wiki/2012_National_Reconnaissance_Office_space_telescope_donation_to_NASA https://en.wikipedia.org/wiki/2012_National_Reconnaissance_O... [2] https://en.wikipedia.org/wiki/Nancy_Grace_Roman_Space_Telescope https://en.wikipedia.org/wiki/Nancy_Grace_Roman_Space_Telesc...

kevin_thibedeau 2y ago
It's also worth adding that the Hubble mirror was made by Perkin-Elmer with a backup made by Kodak. The Kodak mirror is the one with "heritage".
- _djo_ 2y ago
  Technically both Perkin-Elmer and Kodak had heritage, as Perkin-Elmer had made mirrors for the KH-9, but Kodak was making the KH-11 mirrors. NASA initially considered a 3m main mirror for the HST, but opted for a 2.4m mirror especially to take advantage of the existing industrial base for 2.4m mirrors for the KH-11. As it was a proven industrial process that derisked the project and reduced cost compared to a 3m mirror.
  - adastra22 2y ago
    And ironically was the part that failed.
  - jcrawfordor 2y ago
    Producing these large mirrors is a very specialized industry, the projects are extremely expensive, and the timelines are long. Things tend to get passed around between programs, sometimes for reasons as simple as a mirror having been completed after its original customer cancelled it. So it's hard to establish direct causality sometimes, especially since some of the "synergy" between projects was leveraged by the contractors to complete similar tasks without necessarily having direct interaction between the parent projects. It's sort of like air surveillance radar. There's only a few companies that make them, the clients are civilian or military, but the economics mean that both the vendors and customers are incentivized to align the civilian and military systems as much as possible (including through shared-use agreements) in order to make the design and purchasing more economical. Thus the civilian designs are all modifications of the military designs and the military designs are all modifications of the civilian designs, they have essentially evolved in parallel. I used to work on the MRO 2.4 meter telescope (at a small university observatory). Its main mirror was a Hubble design competition prototype that was transferred to the Air Force for intelligence use after the design wasn't selected. The Air Force kept it in storage for a long time and then provided it as part of their incentives to build the 2.4 meter with dual scientific and military applications. A lot of large mirrors used in astronomy and intelligence have stories like this. There's a number of 2.4 meter mirrors out there and pretty much all of them were made for either Hubble, KH-11, or as a shot at both. Radio astronomy is no exception, there's a reason I bring up radar. Most radio astronomy observatories early on incorporated microwave electronics that were designed for weapons targeting radar---sometimes extremely directly, with military radar prototypes having been "looted for parts" by the astronomy commmunity after they were retired. Microwave electronics were very costly to design at the time and it saved everyone a lot of money to reuse everything.

treyd 2y ago

I have a theory that the reason they screwed up the optics initially was because they had to adapt the design from the spy satellite design.

downrightmike 2y ago
No, the identically made mirror that kodak made in parallel was perfectly fine. the first mirror's manufacturer made a mistake

reneherse 2y ago

Indeed the institutional/industrial context of that photo is extremely intriguing and the stories I've heard could fill the pages of a Tom Clancy novel. The level of secrecy at the facility was so rigorous and taken so much to heart that even years after various NRO programs were declassified (decades after program conclusion), the retired civilian personnel I've had the privilege to know were reluctant to speak openly. I will see if I can persuade one retired engineer I know to join this discussion!