Finally, a sensible solution to the Hubble debate - ... that we can all agree on...maybe.

Euler · 2005-02-04 22:58:52

Now you argue against one service mission against replacement cost assuming the replacement will last at least a decade. Hubble required its first service immediately after it was launched. How many years or just months would the new one last before it requires replacement? The point is if you can't get service cost down your alternative is to pay both replacement and service cost for the new one, or worse yet have to replace it completely very frequently such as every year or so. To repeat this point, if you can't get service for Hubble down to where it's affordable, you can't afford to launch any other telescope. Do we want to restrict all space operations to short-duration probes? Or do we shut down the entire space program and save the American taxpayer $16 billion per year (and the Canadian taxpayer $300 million/year).

Hubble was launched with an improperly ground mirror, which was why it’s initial images did not have the expected resolution. It is not like it broke soon after launch, it was defective to begin with. If Hubble II is not broken to begin with, we can expect it to last at least 5-10 years. Saying that we will have to launch new telescopes every year is simply ridiculous.

Your other claims are even stranger. How exactly does the high cost of Hubble servicing missions cause new telescopes to be unaffordable? Why should we restrict ourselves to short duration probes when we have already launched probes that have operated for decades without maintenance? What leaps of illogic did you go through to conclude that NASA should be shut down if Hubble isn’t serviced?

Using the mirror and cameras built for Hubble is generally a good idea. However, as I said my opinion is that we need to ensure we can service a telescope and keep costs down before launching anything else. This will be the last service of Hubble, it's life will eventually come to an end. Then we should launch a dramatically improved telescope. I would suggest starting with medium Earth orbit (MEO) where it's orbit is stable without using fuel. That would require a manned vehicle that can travel from LEO (where any shuttle would park) to MEO and back. An on-orbit tug with a CEV style capsule could do it, but we don't have it yet. Yes, I would like that vehicle to be reusable as well. Also give it a larger mirror; a single-piece large mirror could be launched on edge to keep aerodynamics down. Russia proposed launching a disk shaped lander for Mars on the side of an Energia. If Russia can do it, can't America? Let the engineers debate whether it's better to side launch like Shuttle-C or on top of an EELV. Do you think astronomers would like a 24 metre space telescope? But we're not ready for that yet, so let's keep Hubble.

NASA has been complaining that it is too expensive or too dangerous to service Hubble in LEO with the shuttle. Sending astronauts to MEO via shuttle tug and capsule would be much more dangerous and expensive. If we send a telescope to any orbit besides LEO, then we are not going to have people servicing it.

There is also no point in having a single 24-meter mirror. The sheer weight of something like that would be prohibitive. Even large ground-based telescopes use segmented mirrors now, so it makes no sense not to do the same if you are going to use a mirror that big.

Ad Astra · 2005-02-04 23:31:18

The fact of the matter on http://www.pha.jhu.edu/hop/]The Hubble Origins Probe is that, although it won't be ready until 2010 at the earliest, it will last for a minimum of five years and give us phenominal new abilities like the Very Wide Field Imager. Most importantly, it will enhance our ability to study extra-solar planets.

Technologically, HOP is a cut above Hubble. Whereas HST was based on the KH-11 spy sat designed during the 70's, HOP owes its lineage to the newer Spitzer Space Observatory. It will come in 2,600 kg lighter than HST, orbit at 700 km above the earth, and only require an Atlas V 521 launcher.

The fundamental question is, do we spend the money now to fix the "old and busted" HST, or do we apply it now towards designing and building "the new hotness," HOP?

I vote in favor of financing the future.

Ian Flint · 2005-02-05 00:22:42

I vote in favor of financing the future.

Me too.

I'm an environmentalist and all, but sometimes it is just better to throw something away. What I don't want is for Nasa to scrap the Hubble and then not replace it soon. The public needs pictures -- not UV or X-ray data -- pictures.

Wow the audience and they'll clamor for more. On with Hubble II!

GCNRevenger · 2005-02-05 01:38:44

What are you talking about Robert? You aren't making any sense... we can obviously build a telescope that will operate for many years without any need for servicing, and the length of time between replacements will be long enough that trying to squeeze more life out of an old telescope yeilds poorer science value then launching a new and improved one.

Chandra, SIRTF, and the future JWST all (or will likly) work without servicing through their entire operational lives, so I don't see any reason that Hubble-II could not very likly do the same. There is no need to develop super-cheap servicing capability before comitting to a new telescope, an new one will last long enough that any servicing would be a bad investment.

Also, launching a manned servicing mission to a high Earth orbit where Hubble-II will reside is not likly to happen, since the standard CEV won't be able reach those altitudes without additional propulsion nor could do much there without a cargo bay or grappling arm... adding these would take big money, not counting the parts and engineering of the repair. There is also no need for an orbital tug, since payloads will need attitude control and docking hardware anyway, to say nothing of the safety concerns of pushing people with an "old" engine. The CEV will not be coming to the rescue of the "service often" philosophy to low or high Earth orbit.

And this "last mission" talk? You are being arbitrary (why only one more?) and irrational, it will always be "just one more repair mission" with your wrong-headed philosophy, and you are utterly refusing to make a reasoned analysis of the situation. If it will take a few years between Hubble-I's death and Hubble-II's launch, so be it, then the astronomers' will just have to do without for a while.

1: There is no defenseable rational reason to mount any service mission to the Hubble Space Telescope for the costs & risks involved.

2: In space travel, much of the time expendability is sufficently superior to outweigh any illogical environmental-philosophical concerns.

---
Your mini-MAKS spaceplane is the worst of all worlds, that it would have no destination to fly to often (the ISS? ha!), isn't 100% reuseable (tankage), and isn't suitable for direct return from the Moon (VSE). Not enough volume or payload capacity either for expanded operations (6 crew, light cargo). NASA has also done the right thing and cut funding for the X-43 Scramjet program, since our technology will need to improve signifigantly before a regenerative scramjet that SSTO needs would be possible. Plus, there is still no destination to fly to using said SSTO spaceplane, and money spent on it will not go to lay the foundation for that destination.

---
"...build a tug that could nudge the original telescope to a safe haven and have something to show for it when it's over. A useful tug, perhaps the first of many instead of a one shot doomsday machine. Even if it fails, the engineers will have been thinking in the right direction, one of creation rather than destruction."

Nope, because if you don't save Hubble before its batteries fail, then the whole telescope is worthless. Why? If Hubble loses power, it can no longer keep its electronics warm in the cold of space, and they will be quickly ruined. Pushing Hubble into a higher orbit for some future service mission isn't going to happen.

Plus, raising the orbit requires much more fuel then simply deorbiting, so the deorbiting will be tens of millions cheaper. You would need a pretty big ion tug to do it with too, which doesn't exsist if you go the ion route. Don't think of it as throwing away something useful, think of it as safely disposing something dangerous... which it is, its a gaggle of meteors that are starting to slowly come down to hit us from right over our heads.

---
"I agree the Space elevator is to massive but the Pipline to space isn't!"

Yes it is Errorist, even more massive infact.
---

I am curious about the options for using ion drive propulsion to push Hubble-II out to LaGrange instead of MEO, and use ion engines (vectored ones?) to effect stationkeeping once there. You would obviously want to include a large oversupply of ion propellant.

RobertDyck · 2005-02-05 04:23:22

Hubble was launched with an improperly ground mirror, which was why it’s initial images did not have the expected resolution. It is not like it broke soon after launch, it was defective to begin with. If Hubble II is not broken to begin with, we can expect it to last at least 5-10 years. Saying that we will have to launch new telescopes every year is simply ridiculous.

You assume everything will work perfectly. They assumed that with the original Hubble space telescope, but it didn't.

How exactly does the high cost of Hubble servicing missions cause new telescopes to be unaffordable? Why should we restrict ourselves to short duration probes when we have already launched probes that have operated for decades without maintenance?

Assume the new telescope will require servicing. Mars Pathfinder operated on Mars just 3 days before the battery froze. Mars Polar Lander was never heard from after it started its atmospheric entry sequence; engineers believe when it opened its legs it triggered the ground contact switch and shut off the landing rockets, falling to the ground. Mars Climate Orbiter descended too deeply into the atmosphere and burt up. Shit happens. The Mars Exploration Rovers, Spirit and Opportunity, are working perfectly but that's the second mission after Sojourner/Pathfinder failed. We could list all the missions that succeeded or failed, but the point is you just don't know. Chances are a large complex telescope will need something. If you assume servicing missions will be necessary for the next space telescope, then replacing Hubble doesn't get you out of paying for servicing, it just adds cost for the new telescope.

NASA has been complaining that it is too expensive or too dangerous to service Hubble in LEO with the shuttle. Sending astronauts to MEO via shuttle tug and capsule would be much more dangerous and expensive. If we send a telescope to any orbit besides LEO, then we are not going to have people servicing it.

No, politicians have been saying it's too dangerous, and high-ranking administrators who try to pander to politicians' whims are saying it's too expensive when you add all that crap. They won't out-right say it's affordable if you don't add the unnecessary crap. Astronauts have been saying it isn't dangerous and are willing to go any time as a standard Shuttle mission. As for going beyond LEO, that's what the CEV is for.

There is also no point in having a single 24-meter mirror. The sheer weight of something like that would be prohibitive. Even large ground-based telescopes use segmented mirrors now, so it makes no sense not to do the same if you are going to use a mirror that big.

Segmented mirrors of ground-based telescopes are designed to compensate for atmospheric fluctuations. Astronomers would prefer a single smooth mirror, but truely big telescopes get a blury image from our murky atmosphere. A really big mirror in the perfect viewing conditions of space would get an astronomical view (pun intended).

ERRORIST · 2005-02-05 04:54:23

"Wouldn't micrometeroids fly right through aerogel? Or at least into it. You'ld want some sort of micrometeoroid resistant coating on the mirror, and a micrometeoroid resistant backing. You could keep telescope mass down by exposing the mirror to space like the James Webb space telescope. Needs a sun shade."

Yes they would get stuck in it like the star dust mission but this would happen to any mirror. Cemical vapor deposition would make it stronger and more reflective.Scientist say it can be accomplished.A huge scope could be built at the space station and would be many times less massive than any scope ever built.Also repairable.

GCNRevenger · 2005-02-05 10:27:07

"You assume everything will work perfectly. They assumed that with the original Hubble space telescope, but it didn't."

Yes, that is correct, I assume it will work perfectly. The original Hubble was broken because of a stupid mistake in its manufacture that the builder did not check for. Any Hubble-II mirrors would be checked before assembly this time, I am certain.

Frankly, we can build a telescope with a high chance of working perfectly for its design life without repair. Your assertions to the contrary are a rejection of reality, that NASA has built several space telescopes and a host of space probes that have worked flawlessly the first time.

This is really beside the point anyway... how do you intend to mount any servicing mission to Hubble-II? The CEV lacks a cargo bay, grappling arm, enough OMS fuel for high orbit, or much room internally for the big NASA full-duty EVA space suits. The hatch might even be too small to fit the suit backpack through if it lacks an airlock module. Bottom line is, it will cost big money to modify/upgrade CEV for a Hubble-II servicing mission.

Big enough money that it would probobly be better just to build another replacement telescope! Perhaps a little more expensive, sure, but you would get a longer life out of it and perhaps superior performance.

You also don't seem to know that segmented mirrors in ground-based telescopes aren't for correcting atmospheric effects, but rather so you can build a really big mirror. Adaptive optics correct for atmospheric effects, and they are a black box attached to the secondary mirror.

Speaking of adaptive optics, there is one thing they can't do very well, and that is wide-angle viewing at high resolution. Hubble can't do this very well either even if it is fixed... but HOP can, with its third instrument, a wide-field camera. It will make HOP much more powerful then Hubble-I ever was.

"Mars Pathfinder operated on Mars just 3 days before the battery froze."

Excuse me? That would be because Pathfinders' batteries were not aerospace grade heated batteries, but were high-end commertial D-cell rechargeable flashlight batteries! The Pathfinder was built "on the cheap" so to speak, and we got what we paid for. So too was Polar Lander and Climate Orbiter, both of these were rushed to meet launch dates and pushed to keep costs down, and Dan Goldin pushed too hard. Again, got what we paid for.

Hubble-I also fits in this catagory... the ambitious project was pushed too hard, and its componets were not tested before launch because we were in a hurry to get it up there, being the project was behind schedule... You could even say that Challenger and maybe Columbia too were victims of too much pressure. ...When NASA takes its time and doesn't get in a panic to save money or push schedules, NASA has proved that it can build things with reasonably low risk time and time again.

The original Hubble was concieved back in the early days of the Shuttle program, an orbiting telescope that would be serviced every so often by a "cheap" Shuttle flight. It would even be returned to Earth for refurbishing at the end of its design life and re-launched. Since it was to be based in LEO, the batteries and gyros would be worked very hard, but Hubble is already pretty heavy... So, since Shuttle could visit often on the cheap, the designers included smaller batteries and gyros to keep the weight down fully knowing they wouldn't last even half the design life.

...But that is obviously not the case as Shuttle never lived up to its billing, and CEV will not be much better. Hubble-II however need not be plauged with these problems, since it is lighter and will operate in a higher orbit, the batteries and gyroscopes will be put under far less strain. We will take our time building it, and not get into a panic over the possibility some astronomers won't be happy for a while, and we will get a much better telescope out of the deal then Hubble-I ever was.

GCNRevenger · 2005-02-05 10:46:09

I also want to address this...:

"...high-ranking administrators who try to pander to politicians' whims are saying it's too expensive when you add all that crap. They won't out-right say it's affordable if you don't add the unnecessary crap... As for going beyond LEO, that's what the CEV is for."

Which bascially alludes to me that you think that a Shuttle SM should cost much less then what NASA or the AAS says that it will. Would you please explain your reasoning behind this statement and cite evidence? What "crap" could be cut from the mission that would reduce its price by large double-digit percentages?

Also, the CEV is for carrying people beyond LEO, and will lack a cargo bay, grappling arm, or extended OMS tankage.

Overall, I get the sense that you think that building any intentionally expendable space vehicle is somehow immoral, which is absolutely rediculous.

RobertDyck · 2005-02-05 11:15:36

This is really beside the point anyway... how do you intend to mount any servicing mission to Hubble-II? The CEV lacks a cargo bay, grappling arm, enough OMS fuel for high orbit, or much room internally for the big NASA full-duty EVA space suits. The hatch might even be too small to fit the suit backpack through if it lacks an airlock module. Bottom line is, it will cost big money to modify/upgrade CEV for a Hubble-II servicing mission.

I said mount a CEV capsule on a reusable tug. If you want details the tug could be based on the CEV Resource Module and either arm from the CEV Autonomous Cargo Vehicle or hand from CanadArm2. The capusule would be a CEV Crew Control Module. (http://www.boeing.com/defense-space/space/ses/buildingblocks.html]CEV reference) The tug could be used unmanned to move satellites, and when not used parked at a space station. We have one space station right now, so use that. Gemini and Apollo depressurized the cabin for EVA, the whole spacecraft was the airlock, so do the same with CEV. After all, CEV as currently proposed is just a capsule anyway, not really different than Apollo. Since you could go "EVA" from an Apollo capsule with an A7L or A7L-B suit, why couldn't you do so from CEV? Of course you could.

The EMU is too damn big, it's time to admit it's obsolete. NASA developed the MCP suit as an advanced spacesuit intended for the Lunar surface. Unfortunately it wasn't ready in time for Apollo 11, so they used the A7L. The MCP suit was cancelled in 1972 along with the rest of Apollo. We need a suit for lunar and Mars surface, and the EMU won't do. The obvious solution is to finish the MCP suit. After all, MCP is much safer, lighter, and more dexterous than AL7-B or EMU. Actually, A7L-B is too heavy for Mars and can't bend at the waist, so we need a better suit for Mars. I really want an MCP suit for Mars, let the Moon or service missions from CEV be the excuse.

You also don't seem to know that segmented mirrors in ground-based telescopes aren't for correcting atmospheric effects, but rather so you can build a really big mirror. Adaptive optics correct for atmospheric effects, and they are a black box attached to the secondary mirror.

Adaptive optics work by tilting the mirror segments. The Keck uses hexagon segments with a 2-dimensional gymbal for each. The military developed a flexible mirror that could be deformed for adaptive optics. Always look what's inside the black box, you'll often find a surprise (like dependence on primary mirror design).

"Mars Pathfinder operated on Mars just 3 days before the battery froze."
Excuse me? That would be because Pathfinders' batteries were not aerospace grade heated batteries, but were high-end commertial D-cell rechargeable flashlight batteries! The Pathfinder was built "on the cheap" so to speak, and we got what we paid for. So too was Polar Lander and Climate Orbiter, both of these were rushed to meet launch dates and pushed to keep costs down, and Dan Goldin pushed too hard. Again, got what we paid for.

The Mars Exploration Rovers, Spirit and Opportunity, were also rushed. They had to make the launch window. I watched news reports as they were making it, including video of machinists making wheel armature parts; it was quite a concern whether it would be ready in time. The machinists had to work 24/7 for a few months to get it done in time. Yet, Spirit and Opportunity work perfectly. Flippant remarks like "Dan Goldin pushed too hard" or "got what we paid for" just don't cut it.

Hubble-I also fits in this catagory... the ambitious project was pushed too hard, and its componets were not tested before launch because we were in a hurry to get it up there, being the project was behind schedule...

Actually they had worked on it for several years; in the end it sat in a warehouse (prep-room) for months waiting for launch. They had plenty of time to test everything, and did check everything else several times. However, no one thought to check the mirror for spherical aboration. They did check for smoothness, weight, strength, etc., but didn't think of this one basic test.

Shuttle never lived up to its billing, and CEV will not be much better.

CEV had better be! If CEV isn't much better than Shuttle then why would we spend all that money?!

Palomar · 2005-02-05 11:27:27

The entire Hubble debate is strictly PR and emotion.

*I respectfully disagree. Hubble has returned lots of very good, hard science. One could also reverse the argument, i.e. that folks in opposition are reacting purely out of emotion. Presumptions should be avoided, IMO.

There are now ground based telescopes with more under construction that surpass hubbles resolution. Adaptive optics, as GCNR stated will fruther reduce the Hubbles relevence.

*But those 'scopes are still at the mercy of fickle changes in the weather.

I'm glad they killed the service mission, the money is beter spent on the James Webb space telescope that will be replacing the Hubble.

JWST isn't an optical telescope like Hubble, therefore it is not really "a replacement."

I'm all for the newly proposed plan. 1 billion only? That's a bargain, compared to recent demands for $461 billion for other "stuff" (military/non-science).

--Cindy

Ad Astra · 2005-02-05 11:28:41

I'm an environmentalist and all, but sometimes it is just better to throw something away.

Let's not forget that, no matter what we do, Hubble will be coming down in 2013 or so. The only question is whether it will be working in the period after 2008 due to a servicing mission.

Sending a shuttle to bring the telescope back to earth has already been nixed, as it would be an expensive mission for creating a museum piece and it would pose unneeded dangers to the crew.

RobertDyck · 2005-02-05 11:37:51

Which bascially alludes to me that you think that a Shuttle SM should cost much less then what NASA or the AAS says that it will. Would you please explain your reasoning behind this statement and cite evidence? What "crap" could be cut from the mission that would reduce its price by large double-digit percentages?

The service mission can be conducted as a standard Shuttle mission. You don't need a safe haven, or ejection pod, or ejection seats, or anything else. The Challenger accident occurred when they launched after SRB engineers told them not to. Engineers said you can't launch when it's that cold. For Columbia, NASA was aware there were some tiles lost but not which ones. When Columbia first launched in 1980 it also lost tiles so the military used its telescope in Hawaii to image exactly which tiles were missing. They could have done the same thing to determine if it was safe to land. However, in 1980 NASA released the images to the media; the military was upset that NASA released images showing exactly what capability the military had. They could count exactly which rivets of Skylab were missing, much less Shuttle missing tiles. A single NASA manager for the last Columbia mission had the responsibility of deciding whether to call the military to ask for use of the telescope again. He didn't. One person at NASA tells me that guy doesn't work for NASA any more. Both times a Shuttle was lost it was the result of stupid mistakes. Just be careful and don't make mistakes this time.

Cost: one simple method: don't count the fixed overhead cost of space centers. Shuttle is being returned to flight anyway, so that cost will be incurred regardless of Hubble. Just count the incremental cost for an additional launch. That chops off half a billion right there.

GCNRevenger · 2005-02-05 11:52:33

Ohhh so you would instead launch multiple seperate vehicles to mount a single service mission. A CEV capsule with its service module and the tug vehicle with the replacement parts strapped to its exterior... what a bad idea.

If you would think for a minute, it would be obvious that the tug like you have pictured here wouldn't be very reuseable, since it would need much of its fuel to reach high orbit, and would have to be launched with the repair parts new. Since most of its mass is fuel, and there is no way to refuel it without sending up a maneuverable fuel tank, it doesn't make sense to re-use a chemical tug with Earthly fuel with no RLV... Oh, and we don't have any satelites that need moving around in orbit.

I shouldn't have to remind you that there is no way CEV could go from an ISS orbit to equitorial orbit without a TLI-sized propulsion stage...

So, with about a quarter billion each for the CEV and the tug, and another quarter billion traditionally spent on replacement parts & engineering... a billion dollars for a CEV-based repair mission with margins is not unreasonable.

"However, no one thought to check the mirror for spherical aboration."

And we won't now? ...Mars Polar Lander was an especially eregorious example of pushing too hard and cut costs by skipping software testing, the MERs on the other hand were well funded.

"Shuttle never lived up to its billing, and CEV will not be much better... CEV had better be! If CEV isn't much better than Shuttle then why would we spend all that money?!"

No, I mean that the CEV will not be much better for fixing things in orbit.
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"Adaptive optics work by tilting the mirror segments."

Yeees, on the secondary mirror, not the main mirror.
---

"*I respectfully disagree. Hubble has returned lots of very good, hard science. One could also reverse the argument, i.e. that folks in opposition are reacting purely out of emotion. Presumptions should be avoided, IMO."

ABSOLUTELY NOT! I am insulted Cindy! Have you not been reading what I have been writing? How you can possibly say that!?

GCNRevenger · 2005-02-05 12:00:56

Cost: one simple method: don't count the fixed overhead cost of space centers. Shuttle is being returned to flight anyway, so that cost will be incurred regardless of Hubble. Just count the incremental cost for an additional launch. That chops off half a billion right there.

*LAUGHS*

You surely must be joking... sure, lets just ask NASA to somehow mount an EXTRA Shuttle mission while they feverishly rush to finish the ISS with the remaining orbiters! What a great idea! I am sure that they will be happy to oblige!

Your idea is preposterous, and borderlines on an accounting slight of hand... And unless the mission is mounted in addition to the planned maximum flight rate all-to-ISS flights, then your SM4 flight won't be "marginal" it will just be replacing a $1.0Bn normal flight cost. Not that it matters anyway, since HOP is still a better deal...

...and suppose that they did go with SM4, and the marginal cost for the flight was reduced to half a billion (tank & boosters go for as much as ~$200M a set), and another quarter billion for Hubble engineering/training/parts...

$750M-800M for Shuttle SM4 (with a little margin) versus around $1.00Bn for HOP... and HOP will last double or tripple as long as the repaired Hubble, and will have the superior wide field imaging mode. And won't be 200% of its design life, where something could fail just from age, like the electrical system.

EVEN THEN, assuming a Shuttle launch costs half of estimated, it is STILL a bad deal!

RobertDyck · 2005-02-05 12:13:49

Overall, I get the sense that you think that building any intentionally expendable space vehicle is somehow immoral, which is absolutely rediculous.

Let me explain something to you. I was elected the president of the community organization. I had a problem that the senior administrator refused orders, embezzled money, took credit for everything community members did but excluded those same community members from decision making, and even excluded them from participation in the block party annual even that they had founded. I overruled her but she refused to obey. I confirmed the order with the board of directors, but she challenged their authority. I want to emphasize this: she refused to obey the president and board of directors of the organization that paid her salary. She had split the community into 3 organizations and whenever one organization said something she didn't like, she claimed the other organization had authority. I led the community to merge them back together, primarily to establish clear line of authority. She hired a lawyer and threatened to sue the board of directors. So many directors quit that we no longer had quorum. She got one of the sponsoring agencies to manipulate the election and media coverage so I and the other members of the board were not reelected. Now she continues to embezzle money and run the whole thing without community involvement. The community organization no longer involves the community; it's just a scam to fill her pockets.

Lesson from this story: be careful about any reorganization. It could easily result in loosing everything.

Now the space community is talking about retiring a reusable space shuttle and replacing it with expendable vehicles. The US government has demonstrated a habit of pushing a project until first results, then abandoning it. I'm seriously worried that replacing the Shuttle with an expendable capsule will result in only one flight of that capsule, then it will be abandoned as well. America will no longer have any manned spaceflight capability. After all, it's easy to abandon a vehicle if it has to be built for every mission: just stop building them. It's much harder to abandon a shuttle that's sitting in a hanger waiting to be refueled.

Palomar · 2005-02-05 12:18:38

"*I respectfully disagree. Hubble has returned lots of very good, hard science. One could also reverse the argument, i.e. that folks in opposition are reacting purely out of emotion. Presumptions should be avoided, IMO."
ABSOLUTELY NOT! I am insulted Cindy! Have you not been reading what I have been writing? How you can possibly say that!?

*Um...I don't know if you're jesting or are truly upset? ???

I wasn't implying anyone here -is- in opposition out of emotion. Just that a given point (PurdueUSAFGuy's) could be reversed (anything's possible, you know).

--Cindy

John Creighton · 2005-02-05 12:19:05

The CEV is suppose to be modular and able to doc with other stages in orbit. To me it makes sence if orbital repair is need to have a CEV capable of docking with a robotic arm mounted on an ION tug. That way unlike the shuttle the extra weight needed for the repair platform would not need to be launched each flight.

The CEV would not dock at the ISS but rather near the object it is trying to repair. If it is reasonable for the repair platform to pick up parts and fuel at the ISS that would be just fine. The repair platform could possibly be designed so it could operate autonomously as well. This would give the NASA the choice between autonomously repair missions and crew assisted repair missions. The platform could even first try to repair a satellite autonomously and then later send a crew up if it was clear the platform could not accomplish the mission alone.

GCNRevenger · 2005-02-05 12:25:53

A real shame about your community organization or whatever, and the so-called moral of the story... but it has exactly diddly squat to do with the future of the Hubble Space Telescope and of UV/Vis space-based astronomy in general. Not much to do with future manned flights either.

Shuttle is going away, it doesn't matter if NASA wanted to fly it any more or not, change is going to happen reguardless.

The use of a capsule on top of an expendable rocket has been a sound proven concept for travel in Cislunar space. The rocket that will carry it pretty much already exsists, and only requires modifications. The basic designs of the older capsules could even be dug up.

Small reuseable spaceplanes, intended to fly often and small crews (3-4), do not have a worthwhile destination to justify their higher development costs and reduced flexibility. There is no way such a vehicle can be relied on safely return from Lunar orbit without a revolutionary heat shield material. Nor is a spaceplane with a huge drop tank really reuseable either.

A large reuseable spaceplane, that we will ultimatly need some day, likewise has no destination to fly to in order to justify it. It would also incur extreme development costs.

...So, the only option that makes sense and that NASA can afford to fulfill VSE is to go with expendable capsules and rockets. There will be no spaceplane involved because it isn't practical return it to Earth from the Moon, it is less efficent with its wheels and wings, and will cost more to develop.

GCNRevenger · 2005-02-05 12:31:46

"*I respectfully disagree. Hubble has returned lots of very good, hard science. One could also reverse the argument, i.e. that folks in opposition are reacting purely out of emotion. Presumptions should be avoided, IMO."
ABSOLUTELY NOT! I am insulted Cindy! Have you not been reading what I have been writing? How you can possibly say that!?
*Um...I don't know if you're jesting or are truly upset? ???
I wasn't implying anyone here -is- in opposition out of emotion. Just that a given point (PurdueUSAFGuy's) could be reversed (anything's possible, you know).
--Cindy

I am not kidding, I am upset with you!

"...reacting purely out of emotion..."

This is what I take offense at, the implication that my position is somehow born soley out of emotion and not out of reasoned analysis of the facts of the situation. If anything the Hubble-Huggers are the ones reacting of emotion, since there is no valid rationale to repair Hubble given the circumstances.

GCNRevenger · 2005-02-05 12:35:05

The CEV is suppose to be modular and able to doc with other stages in orbit. To me it makes sence if orbital repair is need to have a CEV capable of docking with a robotic arm mounted on an ION tug. That way unlike the shuttle the extra weight needed for the repair platform would not need to be launched each flight.
The CEV would not dock at the ISS but rather near the object it is trying to repair. If it is reasonable for the repair platform to pick up parts and fuel at the ISS that would be just fine. The repair platform could possibly be designed so it could operate autonomously as well. This would give the NASA the choice between autonomously repair missions and crew assisted repair missions. The platform could even first try to repair a satellite autonomously and then later send a crew up if it was clear the platform could not accomplish the mission alone.

Won't work:

-Hubble-I will be dead by the time CEV is ready
-Hubble Origins (Hubble-II) will be at a higher orbit then the standard CEV can reach
-The tug vehicle would therefore have to push the CEV to Hubble-II
-Ion tugs are too slow to push people, forcing the tug to use chemical fuels
-A chemical fueled reuseable tug does not make sense, and flying a new tug with CEV for each service mission would cost more then replacing Hubble-II.

Palomar · 2005-02-05 12:39:38

"*I respectfully disagree. Hubble has returned lots of very good, hard science. One could also reverse the argument, i.e. that folks in opposition are reacting purely out of emotion. Presumptions should be avoided, IMO."
ABSOLUTELY NOT! I am insulted Cindy! Have you not been reading what I have been writing? How you can possibly say that!?
*Um...I don't know if you're jesting or are truly upset? ???
I wasn't implying anyone here -is- in opposition out of emotion. Just that a given point (PurdueUSAFGuy's) could be reversed (anything's possible, you know).
--Cindy
I am not kidding, I am upset with you!
"...reacting purely out of emotion..."
This is what I take offense at, the implication that my position is somehow born soley out of emotion and not out of reasoned analysis of the facts of the situation. If anything the Hubble-Huggers are the ones reacting of emotion, since there is no valid rationale to repair Hubble given the circumstances.

*GCN: My comments weren't aimed at you in the least. I happened to only begin reading at this thread today (an hour ago), and was simply and only responding to PurdueUSAFGuy. Please don't take it personally, because I've just now gotten around to reading -your- posts. Thus, I couldn't (and didn't) possibly have had you in mind.

-*-

Robert Dyck wrote:

Lesson from this story: be careful about any reorganization. It could easily result in losing everything.

You are so right, Robert. What a truly hideous person you gave as an example. Just an additional comment: I had to deal with a similarly unpleasant person about 10 years ago; one of the most genuinely rotten, vicious persons I've yet personally encountered. Let me just say: The come-uppance is always a distinct pleasure to behold. :laugh:

I hope the person in your example goes to jail. The person in my experience was told "resign or be fired." Which was indeed a public humiliation -- and a well-deserved one at that (a lot of good employees suffered ridicule and extremely shoddy treatment at that person's hands...complete abuse of power, etc.).

--Cindy

P.S.: Sorry, back on topic entirely!

GCNRevenger · 2005-02-05 12:51:31

Fine fine Cindy...

Oh, and if your next post Robert is about "sustainability" and we should build a reuseable manned ITV vehicle crewed by mini-MAKS, the next question is "why?"

The ISS is not a valid reason either, since the US is ending involvement for intents and purposes, and the ISS is worthless in every sense of the term anyway.

You will have to fly the manned spaceplane at least once, perhaps twice to deliver crew and consumeables, and have to launch an expendable rocket with TLI fuel and another rocket or two for lander fuel and surface payload depending on lander size and desired downmass.

Lunar fuel mining to eliminate the fuel launch from Earth is not going to happen initially because of the lack of infrastructure, infrastructure which will need humans to assemble and tend perhaps. Furthremore, even with Lunar fuel, the capsule aproach is not signifigantly more expensive for an ITV/ISRU aproach then a spaceplane, and will be safer since it could handle direct return to Earth.

Ang again, if you intend to bring up old threads even more, the HL-20 nor MAKS never really left the drawing board and is not in any shape form of fasion "half finished" as you might like to believe. It will also cost much more now to build, thanks to inflation and the obviously too-low original price. There is no need to fly often enough to warrent it, especially if the capsule can be reused too.

RobertDyck · 2005-02-05 13:22:51

Oh, and if your next post Robert is about "sustainability" and we should build a reuseable manned ITV vehicle crewed by mini-MAKS, the next question is "why?"

I didn't even need to say it. I drew a picture http://chapters.marssociety.org/winnipe … e.gif]here. Microsoft Paint didn't convert well from .bmp to .gif, it has funny blue shadows. Yes, that's an HL-20 with an alloy 1460 drop tank on one of NASA's 747s. As I said before the lunar transfer vehicle (LTV) can use a refractory heatshield to aerocapture into Earth orbit and aerobrake down to ISS. The heatshield can be fabric over a frame, the same fabric as the outer layer of shuttle AFRSI thermal blankets. I did say the reusable ITV for Mars would use an expendable TMI propulsion stage. Eventually replace the propulsion stage with a reusable advanced system (when it's available) and fuel with asteroid fuel, not lunar fuel. That's after you've established asteroid mines for other purposes. I doubt you'll ever get anything but oxygen and metals from the Moon. The ITV could use the same fabric heatshield as the LTV.

As for "why", remember the life support, avionics, and other spacecraft systems are much more expensive than a fuel tank.

ERRORIST · 2005-02-05 19:23:03

The heck with this bickering none of it makes sense. Lets get back to the aerogel mirror????

LtlPhysics · 2005-02-05 22:53:23

"...build a tug that could nudge the original telescope to a safe haven and have something to show for it when it's over. A useful tug, perhaps the first of many instead of a one shot doomsday machine. Even if it fails, the engineers will have been thinking in the right direction, one of creation rather than destruction."

Nope, because if you don't save Hubble before its batteries fail, then the whole telescope is worthless. Why? If Hubble loses power, it can no longer keep its electronics warm in the cold of space, and they will be quickly ruined. Pushing Hubble into a higher orbit for some future service mission isn't going to happen.

It's a given that Hubble will be scientifically useless way before 2013, whatever its location. It will never be refurbished The idea of building a tug isn't so much about the Hubble as it is about the tug.

Now it could be your position that a tug is a boat with no clear mission, other than the experience of its construction, which is much like the ISS. What would the tug tug? If the current trend is one of expendables, why bother designing tugs?

Simple crude assembly of future probes, perhaps, although the notion of complex constructions in orbit is way oversold.

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Re: Finally, a sensible solution to the Hubble debate - ... that we can all agree on...maybe.

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