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Thread: Moving Hubble near ISS for frequent maintenance?

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    Question Moving Hubble near ISS for frequent maintenance?

    .

    I've read on forums the proposal to move the ISS to another orbit (to become an earth-moon intermediate outpost) or around the moon... clearly that is too complex, costly and useless... but, can we move (at reasonable costs and efforts) the Hubble near the ISS for to have a continuous (and safe) maintenance and upgrade of the telescope without further Shuttle launches?

    now the ISS is at 357 km. altitude 51.64 degrees while the Hubble is at 565 km. altitude 28.5 degrees

    can we do it?

    if we can do that... which is the best way to accomplish the mission?

    and, can the Hubble be reprogrammed to work properly in the ISS orbit?

    .

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    Quote Originally Posted by gaetanomarano View Post
    can we do it?
    ... which is the best way to accomplish the mission?
    Yes it could be done, but the cost would be a significant fraction of launching a whole new Hubble-like instrument. Hubble itself was in a higher orbit so as to slow its rate of descent. Near the ISS, there would ned to be more frequent boosts.

    It would probably have to be done by launching a (yet undesigned) orbital tug about the size of the Saturn IVB. This would need to capture the Hubble instrument and make a few very energetic orbital modifications (three at least).
    Forming opinions as we speak

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    Hi, It certainly makes sense. Give more meaning to the space station.
    Give them something to do.
    I had suggested that they paint concrete bridges with imron paint,to protect them from salt invasive disintegration, but...........I wasn't thinking right.
    They have no interest in long term duration of such expensive structures.
    To my thinking, having Hubble ST in the servicable viscinity of the Space Station indeed has merit,Sir.
    Best regards, Dan

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    As rough as you are on NASA, you trust them to handle the Hubble twice? One, you can't just shift the orbit. Too much delta-v required, so the only option on the table is to reel it in with the shuttle, then bring it down to Earth, then fix what you can on the ground, probably a bit of reconditioning work, then reloft it on the shuttle in an ISS friendly orbit.

    Now, you're still hosed, dude. The ISS bounces up and down in its orbit like a rubber ball, depending on how much drag its facing, and who happens to be launching to it at any given moment, so if they're separated by any measurable length, the constant maneuvering of the ISS is going to alter its orbit subtley to the point where it might not be just a convenient spacewalk away.

    Even worse, the ISS now becomes a visual roadblock for the Hubble, on top of the unholy trio of orbital telescopy known as the Sun, Earth and Moon. Not only does it block some angles, but being a monster of a station with big shiny golden wings kicking out some serious albedo reflection, its an even worse opponent to contend with.

    Finally, the Hubble may be serviced on orbit, but its a cast iron pain in the butt to do. Some of the harshest language ever uttered in space has been fueled by the irritation of astronauts trying to deal with the itty bitty screws on the panels and equipment in this thing. Its serviceable, sure, but its not what you would call maintenance friendly. Lots of lessons in how the station is being put together came at the expense of learning what makes the job more agonizing than necessary after the Hubble servicing missions that have been launched.

    If you want a Hubble-esque telescope on the ISS, design one to be mounted on the ISS that can be maintained through minor spacewalks and internal control with on site trouble shooting. That would be more cost effective than trying to handle the aging elder statesman we have already.

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    I must say, that certainly sounds like an attractive idea. I would guess that there would be complications involved in moving it to a lower orbit, but it wouldn't be the first time Hubble overcame "complications" during it's tenure in space.

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    Quote Originally Posted by antoniseb View Post
    Yes it could be done, but the cost would be a significant fraction of launching a whole new Hubble-like instrument. Hubble itself was in a higher orbit so as to slow its rate of descent. Near the ISS, there would ned to be more frequent boosts.

    It would probably have to be done by launching a (yet undesigned) orbital tug about the size of the Saturn IVB. This would need to capture the Hubble instrument and make a few very energetic orbital modifications (three at least).
    build and launch a new Hubble is not so easy nor cheap

    the old Hubble had a cost of $1.5 billion that means a new Hubble (at to-day's costs) my need $5 billion or more

    assuming to find the funds... the new Hubble needs many years to build it, do the astronauts training, etc.

    when it will be ready, we must add another $600M for the Shuttle launch... that will never happen... since the Shuttle will be retired in 2010...

    then, build and launch a new Hubble is NOT a good (nor cheap) solution

    well... I've read about the NASA plan to repair the Hubble ...and I've found it c h i l l i n g !

    the plan needs two Shuttles, one launched towards the Hubble and another that wait on the launch pad, ready to fly "if something goes wrong"

    but, "if something goes wrong" twice... up to 8-10 astronauts (6-7 for the main mission + 2-3 for the rescue mission) may risk to die in orbit (since no safe haven is possible without an ISS)

    probably, a few astronauts can be saved with some Soyuz launched with only a pilot (and two free seats each) ...if it's possible

    but, I don't think that can be launched more than two-three Soyuz until the Shuttles' life support ends!

    and... add the problem of the Soyuz seats shape vs. the Shuttles' spacesuits... the Soyuz connectors for oxygen, radio, telemetry, etc.

    my suggestion is to scrap NOW the Hubble repair mission, move it near the ISS and repair it in a safer scenario

    move the Hubble doesn't need to build and launch a (now unexisting) space-tug

    my suggestion is to use many (ready available, cheap and reliable) Progress or ATV (or a CREWLESS Shuttle with extra-propellant for the OMS) and do many progressive orbital changes/deorbits

    the only hardware for that mission is a small, light and simple "Hubble-to-Progress adapter" (a device that connects to "something" on the Hubble and has an ISS-like docking port for the Progress) launched with the first Progress

    when the Hubble will be near the ISS, the same ISS-like port will be used for the Hubble's orbital reboost in the same way already done with the ISS (if the Progress has sufficient propellant, a single vehicle can reboost both ISS and Hubble)

    the full Hubble-to-ISS mission may need 5-10 Progress with a (very reasonable) total cost of $150-300 million, much less than one (or two...) Shuttle launches (without consider the value of TEN human lifes, that is PRICELESS...)

    .
    Last edited by gaetanomarano; 2006-Dec-14 at 08:37 PM.

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    Quote Originally Posted by Doodler View Post
    Too much delta-v required, so the only option on the table is to reel it in with the shuttle, then bring it down to Earth, then fix what you can on the ground, probably a bit of reconditioning work, then reloft it on the shuttle in an ISS friendly orbit.
    true, but that option STILL needs (minimum) one (very risky) crewed Shuttle launch to bring back the Hubble to earth... so do main problem/risk remains unsolved... if the astronauts must be anyhow sent in orbit, it's best they go to repair it

    also, that mission can't be accomplished with a crewless Shuttle, since the full operations ("close" the Hubble and put it firmly in the cargo-bay) can't be done with a single, remote-controlled, canadarm

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    build and launch a new Hubble is not so easy nor cheap
    You'd be surprised about the costs of building a new space telescope compared to 2 shuttle missions for the current Hubble.

    my suggestion is to use many (ready available, cheap and reliable) Progress or ATV (or a CREWLESS Shuttle with extra-propellant for the OMS) and do many progressive orbital changes/deorbits
    What are your estimated costs of doing that?

    edit, here you say it:
    may need 5-10 Progress with a (very reasonable) total cost of $150-300 million,
    Have you calculated how many you'd need?

    (edit: can't look it up the costs now: I left my SMAD at ESA )
    With sufficient thrust, water towers fly just fine.

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    Quote Originally Posted by Nicolas View Post
    You'd be surprised about the costs of building a new space telescope compared to 2 shuttle missions for the current Hubble.
    no matter the price... a new telescope must be built and launched while the Hubble already is in orbit and works!

    Have you calculated how many you'd need?
    I've read that each Progress' launch costs $20M, then, 30 of them can be launched for the price of one Shuttle launch
    however, the advantage is NOT the price!
    repair the Hubble (once!!!) needs to risk the life of (up to) TEN astronauts, then, also if, change the Hubble's orbit, needs 100 Progress' missions, it is 100 times better than risk a SINGLE life !!!

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    And the whole point of this is to bring Hubble to a spot where humans can repair it more easily. So the human aspect remains. And as argued, it is not practical/feasible to keep Hubble at spacewalk distance to the ISS.

    btw I found 22 million for progress, so 20 is quite close.
    With sufficient thrust, water towers fly just fine.

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    Quote Originally Posted by Nicolas View Post
    And the whole point of this is to bring Hubble to a spot where humans can repair it more easily. So the human aspect remains. And as argued, it is not practical/feasible to keep Hubble at spacewalk distance to the ISS..
    if the Hubble will be parked at a few miles from ISS it can't be serviced with spacewalks, but a Soyuz or a Shuttle or an Orion can go from ISS to Hubble, service it and back in hours
    but the advantage for the astronauts' safety is the orbit, not the distance
    the ISS is an excellent shelter if the Shuttle is damaged
    but if a Shuttle don't work (while is near the Hubble) the astronauts have no place to go when the life support ends!
    then, the Hubble near the ISS has two BIG advantages: an easy maintenance and no high risks for the space-mechanics

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    Quote Originally Posted by gaetanomarano View Post
    if the Hubble will be parked at a few miles from ISS it can't be serviced with spacewalks, but a Soyuz or a Shuttle or an Orion can go from ISS to Hubble, service it and back in hours
    but the advantage for the astronauts' safety is the orbit, not the distance
    the ISS is an excellent shelter if the Shuttle is damaged
    but if a Shuttle don't work (while is near the Hubble) the astronauts have no place to go when the life support ends!
    then, the Hubble near the ISS has two BIG advantages: an easy maintenance and no high risks for the space-mechanics

    .
    There is no "keeping the Hubble a few miles away". The ISS's orbit is not stable. The ISS adjusts its altitude and orbital geometry every time a new ship is en route, every few months when the orbit falls a certain amount, and sometimes, just to get out of the way of low orbital spacejunk. You cannot say from one month to the next where the ISS's orbit will be because the conditions under which it is forced to operate vary regularly.

    The Hubble has NO capability to keep up with the ISS. None, nada, zero. Ain't there, ain't gonna be there. Its got internal gyroscopes to rotate and maintain a lock on something in its field of view, that's it. If the ISS goes from a 125 x 175 or 125 x 150, or a 150 x 150 orbit, it will leave the Hubble behind and their orbits will no longer coincide. There goes this whole concept of it being "more readily accessible" right out the airlock.

    Contrary to what you might think, there's no way anyone can afford to put a Progress or whatever up every time the space station changes something in its orbit, its just not real.

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    Quote Originally Posted by Doodler View Post
    There is no "keeping the Hubble a few miles away". The ISS's orbit is not stable.
    there is no need that the Hubble is only "a few" miles away from the ISS... 10 or 30 or 50 miles are good... nothing change!
    the most important point is that the Hubble will be on the same ORBIT (or near it) to be repaired, NOT with a spacewalk, but with the same Shuttle/Soyuz/Orion that will go to the ISS (used as shelter, if something goes wrong on the ship)
    ...The Hubble has NO capability to keep up with the ISS.
    I know that (please, read my posts before write you texts) in fact, I suggest to reboost the Hubble the same way the ISS is reboosted: with the engines of the ships launched to the ISS

    last... also if you multiply the problem you quote by TEN, the resulting "bigger list of problems" will be hundreds times LESS than have the Hubble where it is now!!!

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    Quote Originally Posted by gaetanomarano View Post
    I know that (please, read my posts before write you texts) in fact, I suggest to reboost the Hubble the same way the ISS is reboosted: with the engines of the ships launched to the ISS

    last... also if you multiply the problem you quote by TEN, the "result" will be hundreds times LESS than have the Hubble where it is now!!!

    .
    Still a waste of time and money, and cargo space.

    First, you use whatever it is that's docked with the ISS to adjust its orbit, then you move it to the Hubble, and adjust its orbit, then you take it back to the ISS. That's a LOT of wasted fuel on orbital maintenance.

    The Hubble where it is now is fine. It gets one more shot in the arm, then it goes down in 2013 or whenever its systems start to decay. Its been up there a good long time, and another seven years is plenty. By that time, we should be looking at an upgraded space telescope that operates in Hubble's spectral range.

    The lesson of Mir: When an orbital vehicle, even one maintained and repaired regularly by humans, has lived out its useful life, decommission it and replace it with something better. I'd sooner put the money into a newer and more capable scope, even if it ends up costing more than maintaining Hubble, than trying to nurse it along beyond its truly useful operational life.

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    Quote Originally Posted by Doodler View Post
    Still a waste of time and money, and cargo space.
    no, because the Hubble is not the ISS that must rendezvous many ships per year in the right orbit
    the Hubble can be reboosted only when it will be too away from ISS or when it needs to be closer to the ISS for servicing, so, the ships docked to the ISS don't need to go, everytime, to the Hubble and back, but only a few times (when it will be necessary) also, if the ship is a Progress, it can remains docked to the Hubble (for multiple reboosts) then burn in the atmosphere without come back to the ISS
    ...It gets one more shot in the arm, then it goes down in 2013 or whenever its systems start to decay.
    but you need a further, very risky, Shuttle mission
    The lesson of Mir
    not a good lesson!
    the Mir was an old piece of soviet scrap iron BEFORE go in space while the Hubble is an high technology jewel!!!!!
    (please read again the "Opportunity and Spirit lesson"! NEVER scrap an old vehicle if it works well!)
    and... for a new Hubble... please find (first!) the money to build it!

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    The money saved by not making the shuttle capable of unmanned flights and giving it an escape capsule should cover that.
    With sufficient thrust, water towers fly just fine.

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    Quote Originally Posted by gaetanomarano View Post
    but you need a further, very risky, Shuttle mission
    Dear Genius,

    You need a risky shuttle mission to go get the danged thing to move it in the first place!

    Yours,

    The Cynic

    Quote Originally Posted by gaetanomarano View Post
    (please read again the "Opportunity and Spirit lesson"! NEVER scrap an old vehicle if it works well!)
    and... for a new Hubble... please find (first!) the money to build it!

    .
    False juxtaposition.

    Spirit and Opportunity are not serviceable post launch, and therefore invalid in comparison to any low Earth orbital vehicles with such opportunities.

    I could point out to you a number of much more valid spacecraft that have been in Earth orbit, that have been shut down, some in very good working order, and dumped into the atmosphere because of budget limits, operational lifespan issues, and sometimes because of being replaced by superior hardware.

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    Quote Originally Posted by Doodler View Post
    You need a risky shuttle mission to go get the danged thing to move it in the first place!
    sorry Mr. Einstein,
    it's unnecessary if a good automatic device to take it is developed
    ...Spirit and Opportunity are not serviceable post launch...
    now, send a crew to service the Hubble appears to me more risky than send a crew to Mars...
    ...point out to you a number of much more valid spacecraft that have been in Earth orbit, that have been shut down, some in very good working order, and dumped into the atmosphere because of budget limits, operational lifespan issues, and sometimes because of being replaced by superior hardware.
    true (and right) if a vehicle/sat is unnecessary or REPLACED, but the Hubble can't be replaced soon

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    When it was mentioned early in this thread about attaching a booster to the Hubble the size of a Saturn 1B, it's not a great exaggeration. Do you have any idea the amount of energy it tales to move something the mass of Hubble into an orbit of very significantly changed inclination? You would need to design a whole new rocketship/tug of huge capability to do it. Shuttle might be able to shift it's inclination maybe a couple of degrees before exhausting it's OMS fuel...it would take a bunch of impulse.
    And there is no method of just attaching a spaceship to Hubble and reboosting it. It's designed for shuttle servicing and boosting.
    Things aren't as simple as they would seem.

    And, the process of installing ejection seats in the current shuttle fleet does not exist. The differences between Columbia and the others are vast...almost completely different ships. Columbia was something of a "prototype".

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    Quote Originally Posted by gaetanomarano View Post
    well... I've read about the NASA plan to repair the Hubble ...and I've found it c h i l l i n g !

    the plan needs two Shuttles, one launched towards the Hubble and another that wait on the launch pad, ready to fly "if something goes wrong"

    but, "if something goes wrong" twice... up to 8-10 astronauts (6-7 for the main mission + 2-3 for the rescue mission) may risk to die in orbit (since no safe haven is possible without an ISS)
    Based on actual experience, the odds of "something going wrong" are about 2% and probably much less than that considering how careful they're being these days. The odds of both missions getting into trouble would be on the order of 1 in 2500. It makes no sense that you find this "chilling", though it does seem that your feelings match NASA's, in that a mission the sort of which was done about a hundred times with no great concern has now become almost too dangerous to consider.
    Everything I need to know I learned through Googling.

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    How well does longer exposure times possible in higher orbits compensate for a smaller mirror in a telescope? Could much of Hubble's work be done by several smaller, cheaper telescopes in higher orbits? They would be designed for long life using knowledge gained from experience with and since hubble and being cheaper would not be serviced if and when they start to break down. Being higher up they also would not need regular boosting to maintain orbit. They would also be presumably freed from having to use the expensive shuttle infrastructure and could use cheaper expendable rockets. If they were lauched in two parts, the telescope and a booster, it would increase the complexity, but I imagine the booster design could be used for a variety of missions.

    The hubble is about 11 tons and I think that with a little tinkering the Ariane 5 can manage to put about 6 tons into geostationary or near geostationary orbit and an Atlas can perhaps put an 8 ton telescope there. A Delta can apparently put over 10 tons of telescope there, which would be nearly as massive as the hubble.

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    Angular resolution is determined by mirror size. So by choosing a smalling mirror, you decrease the resolution no matter what you do. Maybe you could compensate for it by linking multiple space telescopes up like they do for the VLT (IIRC). But in the root, longer exposre times can only make up for less captured light, not for less resolution.
    With sufficient thrust, water towers fly just fine.

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    Thanks, Nicolas.

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    Compare it to a photo camera. You can't make a detailed shot of an ant by increasing exposure time, only by having a nice zoom lense.
    With sufficient thrust, water towers fly just fine.

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    As a side note, when the Hubble was launched, the Russians weren't part of the Space Station project yet, so the station was planned for a ~28 degree orbit similar to the HST.
    The historical record of Apollo is overwhelming - greater than anything you can glean from questions on a bulletin board. That America abandoned Apollo (and the spirit it engendered) is a travesty. To persistently maintain that it never happened in the first place is nothing short of despicable.

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    Quote Originally Posted by gaetanomarano View Post
    there is no need that the Hubble is only "a few" miles away from the ISS... 10 or 30 or 50 miles are good... nothing change!
    Ok; straight forward, simple questions. And I'm asking this because I don't have the math, and you do, because you wouldn't be making this statement without knowing it.

    What are the orbital speeds of:
    ISS
    ISS + 10 Miles
    ISS + 30 Miles
    ISS + 50 Miles ?
    (assuming no atmospheric drag... ideal conditions)

    What is the thrust needed for a shuttle to transfer from ISS orbit to the above orbits? (just orbit differences, ignoring placement of ISS or hubble)


    By the way; your colors hurt my eyes. I didn't mind the blue, and green's not so bad. But please, no reds, purples, etc.

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    Quote Originally Posted by Dave J View Post
    ...attaching a booster to the Hubble the size of a Saturn 1B, it's not a great exaggeration...
    I find your claim too exagerated
    the Hubble mass is only 11 mT that is (only) 1.5 times the mass of a Soyuz
    if a Soyuz is able to deorbit from ISS altitude (for reentry) with its own propellant, a simple deorbit from Hubble to ISS altitude may need only a small amount of the propellent of ONE Progress
    of course, the Hubble must also change its orbit to, not only its altitude
    but this doesn't need so much propellent as you claim
    since I'm not an engineer, I can only evaluate it "by comparison" (of mass, propellant, gravity, etc.)
    the first version of CEV (with a mass close to the Hubble and 8-10 mT of propellant) was designed to change its orbit from equatorial to polar and back (with the LSAM mass docked!) to accomplish polar LSAM landings
    well, since great part of the CEV/SM propellant was allocated for TEI burning, the propellant to move the CEV/SM (twice) to/from a polar lunar orbit (at 1/6 gravity) with the LSAM docked (in the first part of the travel) must be around 2 mT (2/3 to go with the LSAM and 1/3 to come back without it)
    if we consider the higher altitude of the Hubble and the earth gravity, the Progress' propellant mass to change the orbit/altitude of the Hubble may be in the range of 4-6 mT ...that is the propellant of a dozen of Progress..
    ...design a whole new rocketship/tug of huge capability to do it...
    I don't suggest to design and build a special booster to accomplish the mission in a single launch since it needs too time and money but to use many Progress launches to change the Hubble orbit/altitude step by step
    ...Shuttle might be able to shift it's inclination maybe a couple of degrees before exhausting it's OMS fuel...
    but the Shuttle mass is 6-7 times the Hubble!
    ...there is no method of just attaching a spaceship to Hubble and reboosting it...
    its not a so complex problem to solve for the change of orbit/altitude, also, when the Hubble will be near the ISS a better (fixed) docking port can be assembled with a spacewalk
    ...ejection seats in the current shuttle"...
    it need hard work, of course, but it's simpler than build an escape module

    .
    Last edited by gaetanomarano; 2006-Dec-15 at 03:01 PM.

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    Quote Originally Posted by gaetanomarano View Post
    the Hubble must also change its orbit to, not only its altitude but this doesn't need so much propellent as you claim
    Changing the apogee and perigee's altitude is small compared to changing the orbital inclination. Changing that would take about half as much energy as just getting Hubble into orbit in the first place. Don't forget that this device also has some mass of its own to secure Hubble into a safe position for the manuevers.
    Forming opinions as we speak

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    Quote Originally Posted by ToSeek View Post
    Based on actual experience, the odds of "something going wrong" are about 2% and probably much less than that considering how careful they're being these days. The odds of both missions getting into trouble would be on the order of 1 in 2500. It makes no sense that you find this "chilling", though it does seem that your feelings match NASA's, in that a mission the sort of which was done about a hundred times with no great concern has now become almost too dangerous to consider.
    it's a too optimistic (then, risky) evaluation of the problem
    it's true that the 25 years experience gives only a 2% of accidents, but this figures includes the flights of the full fleet and the early launches done with the Shuttles young, fresh from factory and perfect!
    now, the Shuttles are old, have many new problems every day, the foam risk at every launch, etc. etc. etc.
    then, now, the risk of failure in higher than past (this is the main reason I suggest to launch the Shuttle crewless or with an escape module/seats!)
    about "something goes wrong twice"... that doesn't means only "two accidents" but (simply) a (modest) in-orbit-failure of the first Shuttle and a (very common) delay of the second Shuttle!
    just imagine this scenario: the first Shuttle launch goes ok, it reaches the Hubble and repair it, but, at the end of the mission, it doesn't work or can't come back safely (your choice of the problem... tiles, OMS, energy, etc.)
    the second Shuttle must be launched within a few days (until the life support of the first Shuttle ends!) but it can't fly in time due to one or more (small or big) delais (again, your choice of the problem: foam, weather. tank sensors, SSME, etc.) and the astronauts in orbit will die

    .

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    Quote Originally Posted by antoniseb View Post
    Changing the apogee and perigee's altitude is small compared to changing the orbital inclination. Changing that would take about half as much energy as just getting Hubble into orbit in the first place. Don't forget that this device also has some mass of its own to secure Hubble into a safe position for the manuevers.
    I am not able to do an exact calculation, but, if it needs more than a dozen of Progress, that doesn't matter if compared with the BIG advantages of avoid two (very risky) Shuttles' missions and have the Hubble near the ISS
    also, each Progress costs $22M, then, 30 launches equals the price of one Shuttle missions... I think it's very cheap!

    .
    Last edited by gaetanomarano; 2006-Dec-15 at 04:16 PM. Reason: grammar

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