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.
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.
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.
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.
The two telescopes that I worked on that had no such problems were XTE (aka RXTE) and AXAF (aka Chandra). I only did a little bit of work for AXAF, but I worked on XTE for years. In addition to some other miscellaneous software, I wrote the code that let the scientists configure the parameters of the on-board data processing computers.
There were some serious issues with AXAF, though. The CCDs were damaged by some sort of unexpected particle radiation. Prior to this damage, the CCDs on AXAF were the most carefully calibrated CCDs ever manufactured. Or so I was led to believe. And the damage, although not fatal to the mission, did ruin the calibration. This was pretty discouraging to a colleague down the hall, since he had spent years making it so perfect.
As I understand it, the designated time arrived and the canister was supposed to be open, but wasn't. A latch had failed. One or more of the payloads inside the canister started deploying themselves anyway, wrecking themselves and everything else inside the canister.
The telescope in question wasn't worth terribly much, at least compared to a Shuttle launch, which at the time cost at least $500 million, not including the cost of any payload, so even if the telescope hadn't been ruined, trying to rescue it wouldn't have made any sense.
There were some other satellites in the canister, however, and IIRC, the total value of all the satellites was nothing to sneeze at.
No, generally when a launch fails the satelite doesn't reach it's final orbit. Either part of the shroud (rocket nose fairing)( fails to release and the extra drag makes it reenter - or even if it is in a stable orbit the lack of power causes it to freeze.
A manned Shuttle service mission cost something like $500M / $1Bn (depending on how you do the accounting) so it was never really practical to retrieve a damaged satelite from a purely economic perspective.
Some colleagues of mine had an even worse day. The launch went perfectly but the lens cap released while the Earth was in the IR camera field of view and the entire mission coolant was burned off in a few minutes.
So it's these telescopes that were the entire reason for the shuttle program in the first place, wasn't it? The conventional rockets could launch satellites of most sizes all day long, but something the size of the Hubble required a vehicle with a large "mysterious payload" capacity.
Atlas rockets and the future Falcon Heavy from SpaceX are able to carry more, bigger, heavier payloads than the space shuttle ever could. What makes the Shuttle unique is that it could bring stuff back from space. Hubble could have gone up on any of the other rockets, a shuttle is the only thing that could bring it back though.
Not quite. The Shuttle's wing design was an airforce requirement (high cross-range) to allow a launch from California, release or retrieve a polar orbiting satellite and return to US soil.
The idea is that if you track the launch vehicle's path you can get a good estimate of where to look for the payload and so you know it's orbit and when to not doing anything suspicious out of doors. KH satelites are so big that you can see them in orbit anyway and are difficult to move to an other orbit very often. If you had the ability to maneuver in flight while over friendly territory the opposition couldn't get a good estimate of where you had been.
Since the Vandenburg facility was never used and shuttle flights from the Cape were pretty public and a payload this big was pretty obvious then it's unlikely that it was used.
Buran was probably a pure case of "what do they know that we don't" plus politics overriding the engineers saying that it didn't make sense.
Yeah, the Shuttle never flew a polar orbit, nor did it ever land at Vandenberg. Fun fact: the only reason the Air Force had a say in the Shuttle's design is because the Shuttle was supposed to be a fast-turnaround spaceplane with enough launch capacity to serve as the standard spacelaunch system for the entire government, including NRO flights.
Then we actually flew the thing. Whoops, the heat shield falls apart after reentry. Whoops, the turbopumps can only last one flight. Therefore, six months of downtime between flights. Whoops, Columbia and Challenger! Therefore, the fleet might be grounded at any time, for years at a time, since the Shuttle can't be flown without humans, (Landing gear deployment requires pulling a manual lever, on the insistence of the astronaut corps. Otherwise it was entirely automatic) and the public doesn't like it when astronauts are killed.
Thus the military returned to conventional rockets. They even built an unmanned spacecraft for the "go up and steal a satellite" mission the Shuttle never ended up performing: the X-37.
Given the USSR also built the Tu-144 so you're probably right about it being a case of envy, though the shuttle is fairly unique in that it can retrieve things from space and bring them back, something not practical in a Soyuz or Dragon-type vehicle.
I can imagine if the military had orbit-capable telescopes like those sitting around, there must be many ground-based ones used to track other satellites.
Retrieving satelites never really held water.
Your own payloads would have to be very very valuable to be worth the cost and risk of manned launch and rendezvous and the shuttle couldn't land with something the mass of HST or a KH spy sat
Snatching an enemy's property is even more risky - as soon as the opposition has the capability you would fit your special toys with an anti-handling device. I don't work on the 'dark side' but I'm betting that anything special has a self destruct anyway just in case a launch goes wrong and it is retrieved.
You could even launch a whole constellation consisting of just a proximity fuse, a few kg of C4 and some ball bearings and wait for the other side to go fishing in their $billion space plane.
There was a very large US program to send up a photo sat manned, take pictures, and send back to earth in very small pods. It is a good read I will update post if I can find video.
I was only involved in Hubble after it was built, but my boss had conference proceedings from the early 70s were it was proposed that it would be a Skylab type space station with a crew of 3 loading photographic plates into a telescope and then developing them!
A return was considered in place of the COSTAR servicing mission, I can't remember if there was a 'safety margin' in that figure or there was another reason - but it was rejected for safety 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.
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.