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NASA has a fully functional copy of Hubble "sitting around" at Goddard Space Flight Center as well. If something goes wrong in space, fabrication of replacemen

by jcnnghm 14y ago

NASA has a fully functional copy of Hubble "sitting around" at Goddard Space Flight Center as well. If something goes wrong in space, fabrication of replacement components and the training of the astronauts that will fix it does not occur in space. It is invaluable to have an exact duplicate on the ground for this reason. Interestingly, the total 2010 US Space budget was $64.6B. The entire rest of the world combined spent only $22.5B. NASA's 2010 budget was $18.7B. Many programs that people think are NASA projects are actually defense projects. For example, the GPS system is not included in NASA's budget, it's spearheaded by the Air Force Space Command, and comes out of the Defense budget. Chances are the main satellites that these are duplicates for have been decommissioned, so these are no longer needed. I would guess they are actually two distinct but similar designs, and not two copies of the same design. I would assume NASA already determined that the risk of these satellites failing and NASA being incapable of fixing them is outweighed by the desire to have higher powered telescopes in space. My mother has worked in the thermal blanket lab at Goddard for years. Several years ago, she got one of the engineers working on the James Webb Space Telescope to take her and I on a tour of the clean room where they are fabricating one of the core components, the micro-shutter array. The micro-shutter array is an array of 65,536 shutters on an area about the size of a postage stamp. We got to go into the clean room and see the entire process. It is very similar to the process used to fabricate semiconductors, and I think they were operating at about the 60nm level. The idea of the micro-shutter array is that each shutter can be independently operated to shut out interfering light sources, so that the telescope can look much further back in space and time for deep fields. These should be spectacular. Instead of imaging the entire shutter area as the Hubble does, JWST will be able to close all but one micro-shutter which should allow very long exposure times, and the ability to see extremely distant objects. More on the array at http://www.jwst.nasa.gov/microshutters.html http://www.jwst.nasa.gov/microshutters.html. Edit: Also, the Hubble is huge. It is a cylinder with a diameter of perhaps 15ft and a height of roughly 40ft. Pictures really don't do it justice, I had no appreciation for the size until I saw it. I know my mother did some of the thermal blanket fabrication (think the tin-foil looking stuff on the outside of spacecraft) for Servicing Mission 4.

excuse-me 14y ago
There isn't a fully functional flight spare of Hubble sitting in bubble wrap waiting to fly. There is a mockup of the Hubble structure and there were flight spares for SOME optical components and some parts of instruments. The mockup is to train astronauts on instrument swap outs. Many of the instruments and the current solar panels aren't even Nasa builds The "better than hubble" telescopes are old keyhole era spy sats, this is the design Hubble was originaly based on. It's also partly the reason for the original Hubble screw-up. The contracts for Hubble went to companies that had experience building 2.4m mirror space telescopes (nod+wink). But security walls in the suppliers meant that the people who had build these spy sats didn't work on Hubble or pass on their knowledge - then oversight of the Hubble build process was hampered by security concerns that meant NASA QC engineers never got to see the mirror being built. A few other points. The cost of the Hubble 'airframe' was a small part of the space telescope cost, compared to the launch and service missions, the building of the STSci and the 1000 of professors, postdocs, researchers and students that it funded. Just the cost of storing it in a clean room for 3years after Challenger was estimated at more than raw commercial build cost. The JWST isn't just a better Hubble it's a completely different concept - actually designed as a scientific instrument rather than compromised by being a spy sat design built to justify the Shuttle launch - as HST was.
- nessus42 14y ago
  I have to second this. I worked on two NASA space telescopes (both X-ray telescopes), and although we had on the ground something like the telescopes that were flown, the equipment on the ground was not flyable, and if the launch rocket had blown up, we would have been SOL. In fact, some of the folks down the hall from me had a telescope they were working on fail to deploy properly after launch due to the canister containing the telescope not opening. There was no spare telescope--they had to start over from scratch.
  - samstave 14y ago
    So there is an unopened space telescope sitting in a canister in orbit? Wouldn't a device to open. The canister be cheaper than starting from scratch?

by jcnnghm 14y ago

excuse-me 14y ago

There isn't a fully functional flight spare of Hubble sitting in bubble wrap waiting to fly. There is a mockup of the Hubble structure and there were flight spares for SOME optical components and some parts of instruments. The mockup is to train astronauts on instrument swap outs. Many of the instruments and the current solar panels aren't even Nasa builds The "better than hubble" telescopes are old keyhole era spy sats, this is the design Hubble was originaly based on. It's also partly the reason for the original Hubble screw-up. The contracts for Hubble went to companies that had experience building 2.4m mirror space telescopes (nod+wink). But security walls in the suppliers meant that the people who had build these spy sats didn't work on Hubble or pass on their knowledge - then oversight of the Hubble build process was hampered by security concerns that meant NASA QC engineers never got to see the mirror being built. A few other points. The cost of the Hubble 'airframe' was a small part of the space telescope cost, compared to the launch and service missions, the building of the STSci and the 1000 of professors, postdocs, researchers and students that it funded. Just the cost of storing it in a clean room for 3years after Challenger was estimated at more than raw commercial build cost. The JWST isn't just a better Hubble it's a completely different concept - actually designed as a scientific instrument rather than compromised by being a spy sat design built to justify the Shuttle launch - as HST was.

nessus42 14y ago
I have to second this. I worked on two NASA space telescopes (both X-ray telescopes), and although we had on the ground something like the telescopes that were flown, the equipment on the ground was not flyable, and if the launch rocket had blown up, we would have been SOL. In fact, some of the folks down the hall from me had a telescope they were working on fail to deploy properly after launch due to the canister containing the telescope not opening. There was no spare telescope--they had to start over from scratch.
- samstave 14y ago
  So there is an unopened space telescope sitting in a canister in orbit? Wouldn't a device to open. The canister be cheaper than starting from scratch?