Posted by
Hemos
on from the good-week-end-for-NASA dept.
lonedfx writes "After nine delays, STS 103 has launched and its crew should service the Hubble space telescope in the next few days. Hopefully Hubble will be soon back to give us great pictures to stare at. "
Does anyone know if the sort of problems the Hubble is having are "routine" Yeah; they're routine. The telescope was designed to be upgradable and reparable, and the gyroscopes -- the main problem -- have lasted longer than was originally anticipated. It was never a question of if the gyroscopes would fail, but when.
As for beset by problems: okay, the focus thing when it first went up was unfortunate and expensive, but since then, its problems were those of any satellite with a shitload of different technologies aboard. Its original aim -- to spot extra solor planets -- has never been achieved, but it's been a stunning success in every other regard.
I for one don't trust the shuttle to be in the air in 11 days time.
Don't worry, neither does NASA. They said they'd cut one "EVA" (spacewalk) which would have covered some peeling paint(!) on rails around the telescope, in order to get back in time for Y2K. They're concentrating on replacing the 6 gyroscopes this time, according to the local talking heads on TV.
I saw the launch live last night (I live in Melbourne, FL) and it was lovely. No matter how you feel about the government's space program (I'm ambivalent-to-negative on it, much as I'm a fan of space exploration in general) a night launch from the Cape is a beautiful sight. JMR
Yeah all the coverage makes it sound like the thing is falling apart. These reporters must be of the mind that when you buy a car, it's already got oil in it, why would you have to change it? Just wastes more of my/taxpayers money. Chuckleheads...
The big secret that nobody at NASA wants to tell anyone is that it wasn't really the Gyroscopes that failed. Some technician dropped his ham sandwich into the optical relay and ever since launch the cheese in it has been heating up and cooling down, thus forming a thin layer of cheese across the mirror. This is why we get all those stunning colorful shots with a yellow tint. The observatories were obviously annoyed so they sent up the shuttle to recover the ham sandwich.
-- Contrary to the popular belief, there indeed is no God.
Re:Lest We Forget...
by
Anonymous Coward
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· Score: 4
"Except that I read somewhere that, unofficially, the shuttles' software has never been able to handle a year change correctly, anyway..." You are right, the software cannot handle a year-end rollover. The navigation routines that tell the orbiter where to de-orbit perform their calculations in the M50 (Mean of Aries 1950) coordinate system. This system is an inertial coordinate system, which means that it is referenced to a fixed point in space. Now, in order to deorbit into the right window, we need to tell the orbiter how the earth is positioned within this inertial reference frame. To accomplish this we need to use a Rotation Nutation Precession (RNP) matrix to transform the orbiter's position in M50 coordinates to a position in Earth Centered Earth Fixed (ECEF) coordinates. The RNP matrices are computed on the ground for various times during the year and each are only good for about 3-months on either side of their designed time. If a launch slips over the year end, the RNP matrix is no longer any good, no matter how stale it is (1 day or 1 month or [1 year - 1 hour]). The good news is that we have now designed an improvement to the flight software that calculates the RNP matrix on-board. This would be able to get us out of this predicament, but I would venture to guess that the program still would never have a mission that would cross the year-end boundary in orbit. Actually, we could probably get out of it by patching a new RNP while in orbit, but that is a risk that the program is most likely unwilling to take. - These views are mine and do not necessarily represent those of my employer.
Purpose? I don't think so.
by
Tau+Zero
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· Score: 3
Its original aim -- to spot extra solor planets
BZZZT!Sorry, but thanks for playing.The biggest original purpose of the Hubble Space Telescope was to determine the value of the Hubble Constant by calculating the luminosity of Cepheid variable stars in galaxies too distant for ground-based telescopes to perform the work.Extra-solar planets cannot be reliably detected by their reflected light at this time (only one freakish case has allowed this), and Hubble has not been involved in the detection of these planets; it has been done with ground-based telescopes collecting extremely precise spectrometry data. -- The Karma Century Club is taking new members.
-- Time is Nature's way of keeping everything from happening at once... the bitch.
The BBC reports that the mission will be shorter than originally planned since the launch was delayed and the "agency did not want astronauts in space over millennium eve in case of computer problems."
Kinda worrying that NASA aren't so confident about their Y2K readiness. Guess you have to be when you're so much in the public eye. But what happens if they have some other non-Y2K problems that hold them up further... into the new millenium?
Even if NASA had 100% confidence in the systems aboard the "manned space truck" they'd have to worry about all the ground systems. And even if they had 100% confidence in all the ground systems they have to consider that their are factors they cannot control on the ground. What if third-party systems like power and water fail. What if some satellite based communications fail because of third-party ground systems? What if they run out of champagne? (you can't have a dog-and-pony-show celebration without champagne!) And I'm sure their official checklist includes fear of millenial terrorists attacking the space shuttle, and the melissa virus doing some non-descript "bad thing" to their computers.
The bottom line is that, weather the threats are real or imagined, they can't control everything so they should error on the side of caution. It is just good risk management.
The end-of-year rollover has been a recurrent source of problems in many programs that predict the orbits of spacecraft, such as antenna control software for ground stations. Even without the year 2000, it is a time to be avoided. The ranges (Cape Canaveral & Vandenberg) also are partially shutdown at the end of the year so that people can take holiday vacations.
It's not just a function of old age. The two major delays this mission were to check the wiring (after finding faulty wiring on another shuttle) which is purely a safety consideration and to repair a dented pipe, which was probably caused by a freak occurence. These are problems which could strike any space mission, new or old, and doesn't really have anything to do with the age of our shuttle fleet.
Granted, the shuttles are old, but these delays are simply the result of the Challenger incident and NASA's goal to keep people alive. The shuttles themselves are probably in better shape than your current car, and they're certainly in better shape than any car you've owned for 20 years.
Of course, I'm not saying that a newer design isn't warranted (and NASA has actively been researching towards that goal), but don't dismiss the shuttles because of the delays. It really isn't 'bad design' that's causing them. I think 20 years from now we'll still be able to use the shuttles, even if it's in a workhouse capacity (see the old Nebula-class starships from Star Trek, ST:TNG, and ST:DSN if you need an example).
As for beset by problems: okay, the focus thing when it first went up was unortunate and expensive, but since then, its problems were those of any satellite with a shitload of different technologies aboard. Its original aim -- to spot extra solor planets -- has never been achieved, but it's been a stunning success in every other regard.
True.... most of which the general public never sees. The primary purpose of that big 'scope was to do research in the infared and ultraviolet and radio frequency realms, things which don't need that big mirror with its "contact lens" to work right. Hubble started sending good science within a couple of weeks of finishing outgassing, before they even planned a mission to "fix" it. The visual-spectrum lens system is just there to send back pretty pictures and make the public go "ooh" and "ahhh" and "vote for this, mister congressman." It serves little scientific value.
Is it really worth it? Hafta ask somebody else, I was just the sysadm for a sister project when the thing went up. Didn't stick around for the results.
Glenn Stone former Data Validation system administrator NASA UARS (Georgia Tech) now under contract to another fine airplane company in the Seattle area
I don't strap my car to two solid rocket boosters and send it into orbit, at least not regularly. This is a very bogus comparison, the tolerances (e.g. heat, stress) required for normal operation of a car, and the tolerances required for a man rated launcher are not comparable.
You also don't baby your car the way that NASA babies it's space shuttles, nor do you meticulously repair the maybe slightly defective parts the way NASA does with the space shuttle. Both vehicles are designed for certain limits, and both operate within those limits.
Unfortunately is bad design thats causing the delays, the shuttle design was a compromise (much like the current ISS debacle) due to repeated budget cuts. Initially design targets were to have something that could fly and turn around again in a matter of days or weeks, they were looking for a shuttle that could fly (at a minimum) twenty or thirty times a year. What they ended up with falls very short of the mark, something that was actually more expensive to launch than a normal rocket. The shuttle is an aging launcher, with design compromises at every turn, it shows.
Compromise of the initial design vision isn't what's delaying the shuttle in any way. If the shuttle was built to be used 20-30 times a year, it still would undergo the safety checks that NASA is giving it now, and if they wiring was bad on one of those shuttles, I'm sure NASA would take the time to check each one, and it would probably still have an excessive number of miles of wiring. What's causing the delay here isn't the design of the shuttles, whatever form that design may be, but NASA's anality (analism, analness?) about safety. Rightly so, I might add, since protecting the lives of the passengers should be the top priority.
Hopefully, VentureStar won't be as big a disappointment, although personally I still think they should have gone with the Delta Clipper (at least they had a working prototype in hardware).
Yeah, and in the meantime, what do you use? The current 'bad design' that's really only failed once in 20 years of usage, right? NASA's not going to make the mistake again of stopping all space flight for development of a launching mechanism when they have a perfectly good one. And given the VentureStar or the Delta Clipper's design snafus, I'm glad they're still researching it.
No way, we've already stretched the design lifetime well beyond the inital estimates.
Then how can it be a bad design? It may not fulfill the initial design vision, but as anyone who's ever worked in design can tell you, the vision changes as you work on a project. The fact that the shuttles have lasted this long with only problems to the launch device, not the orbiter itself, shows exactly how great and durable a design it actually is.
The BBC reports that the mission will be shorter than originally planned since the launch was delayed and the "agency did not want astronauts in space over millennium eve in case of computer problems." Kinda worrying that NASA aren't so confident about their Y2K readiness. Guess you have to be when you're so much in the public eye. But what happens if they have some other non-Y2K problems that hold them up further... into the new millenium?
It's not a matter of confidence; NASA's primary responsibility isn't showing off their confidence, but the safety of the astronauts. All things considered, having crew on orbit over the new year just isn't a good idea. The risk may be small, but the consequences could be fatal.
Boosting public confidence is the job of agencies like the FAA, which is making a point of having its administrator in flight over the Y2K clock tick (except she keeps getting flights cancelled out from under her, due to low demand).
As for problems not related to Y2K, it's more likely that they would then merely cut the mission short. The chance of an in-flight failure that prevents a return to Earth (e.g. cargo bay door stuck open) is the same as before, and nobody wants to think about that. There simply isn't any contingency for a rescue of a disabled shuttle. ----
-- lake effect weblog {Network engineer in Chicago--looking for work!}
That sounds a little extreme just because of some launch delays (which have *always* been the norm with the space program). But if you want to look at a commercial reusable launch platform, take a look at this site.
-- Admit nothing, deny everything and make counter-accusations.
Can anyone tell me why the BBC has better intel on the NASA/shuttle situation than anybody IN the US? It just seems kinda odd that with all the DIRT our local media can dig up why can't they get any REAL inforamtion on what is going on at NASA.
This isn't "intel", it's been publicly announced that they chose to launch Sunday but trim one of the spacewalks (the insulation, which has the lowest priority, will now be part of repair mission 3B in 2001).
It is, however, true that NASA has a set way of dealing with the media, and are notorious for preferring those reporters who will play ball with their PR line. The constituencies within NASA who deviate from the official story are punished or exiled. The NASA public affairs office can be extraordinarily petty (viz. the way they tried to require that all Hubble photography carry only the NASA logo, no matter that the Space Telescope Science Institute prepared it or that European Space Agency equipment was used).
The media, in general, mostly run stories about NASA when they have: a) a ready-made success story b) pretty pictures c) a major failure c) 1) if major failure within last year, also report all minor failures in ominous tones
----
-- lake effect weblog {Network engineer in Chicago--looking for work!}
Odd... it seems to me that every time I turn around, Hubble has broken again... are we attacking the symptoms here or the disease, so to speak?
You might want to learn a little more about the Hubble mission. When this thing was put together, several servicing missions were anticipated to replace components as the wore out, and to upgrade or swap out instruments. These missions are planned on a three year cycle.
The ORIGINAL plan was to bring the Hubble back to earth for refitting every 5 years, however the ability of shuttle crews to do in-orbit servicing has made this unnecessary.
IN FACT, the Hubble has been one of the greatest successes of the entire space program.
This mission not only includes replacement of gyroscopes (that lasted longer than originally planned), but upgrading some instruments and the main Hubble computer system.
Venture Star killed the real competition
by
Tau+Zero
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· Score: 5
Back in the days of the unjustly-maligned Strategic Defense Initiative, there was a group of people who were charged with getting SDI satellites into orbit. They had advantages over NASA in this regard. They were tied to neither the existing launch-vehicle fleet nor the high-cost aerospace contractors; this let them examine things afresh. They took out a clean sheet of paper and tried to design, not a vehicle, but a program for getting a vehicle.
What they wound up with looked very different from the Space Scuttle and VultureStar. It was a squarish bullet, covered in thermal-blanket material originally developed for the Shuttle. It was not terribly fussy about its engines; it could have flown on J2's or RL-10's. The innovations were several:
It was designed to land tail first, under power. This takes advantage of the engines, which are along for the ride, to provide landing capabilities. This eliminates the need to be able to glide subsonically; the glideslope, flare and landing maneuver required by Shuttle (and VentureStar) is unnecessary.
It did not have wings. This saved a great deal of weight in the airframe.
Its landing gear was a system of struts and pads. No wheels required. This saved more weight.
The pilot went away also. When so many missions are just putting unmanned birds or cargo in orbit, why carry people along all the time?
The vehicle was to be called the Delta Clipper, or DC-1.
The development program was very innovative: build a little, fly the results, roll the lessons learned back into the next generation. The first vehicle (low-altitude atmospheric testing, designed to prove some of the required maneuvers for takeoff, landing and aborts) was the DC-X. The second-generation, subscale, orbital (with no payload) vehicle was to be the DC-Y; it would have tested fuel tankage, weight-saving and thermal-protection systems.
The total cost of DC-X and DC-Y was to be less than one year's budget for the Shuttle program.
SDIO borrowed stuff from everywhere to build DC-X. They got 4 RL-10's on loan from Rocketdyne, had the aeroshell built by Scaled Composites (Burt Rutan's outfit), and reprogrammed an airliner autopilot to fly the bird. DC-X was a phenomenal success, proving everything it was set out to do. And then SDIO, shutting down and getting outside of their bailiwick (which was NOT to develop commercial spacecraft launchers), turned the program and the prototype over to NASA.
NASA completed the scheduled test flights and then crashed and burned the prototype when someone neglected to reconnect a landing-gear unlock line before flight. Accident? Deliberate? No one's talking.
After the destruction of the DC-X, NASA let a contract for the development of a successor to the Shuttle. The developers of the DC-X had a bid in, but the contract was awarded to a company whose vehicle:
Had no development record;
Could not be delivered for many years longer;
Had a much more expensive development program.
On the other hand it took off vertically like Shuttle, landed on (and required) a runway like Shuttle, and required a new engine development program. The winner was not the low bidder. Can you say "more pork"?
When the winner of the contract was announced, the counsel for NASA was present. This was apparently to keep the DC-1 proponents from getting the idea of suing to either get the contract or find out what funny business had gone on. In the mean time, the Shuttle and its standing army of maintenance people are still working, and there's a lucrative R&D contract for the VentureStar (even though it's having serious difficulties with its composite LH2 tanks delaminating). It's great for everyone except the taxpayer and people who might benefit from flying satellites cheaper; IOW, it sucks. -- The Karma Century Club is taking new members.
-- Time is Nature's way of keeping everything from happening at once... the bitch.
Does anyone know if the sort of problems the Hubble is having are "routine" or if this was a problem inherent in the design of the telescope? It seems (and maybe I'm just too influenced by the media) that this project has been beset by problems from the very start. Too bad too...its images are breathtaking.
If you want the whole story, I highly recommend reading Eric Chaisson's The Hubble Wars ; he was a senior scientist on the project during the pre-launch and commissioning, and is a tremendously detailed but engaging scientific writer. Read it, and you'll never look at NASA the same way again. (For a similar perspective on people in space, read Dragonfly.)
The problems with Hubble are too many to enumerate here, but they begin with the overselling of the shuttle's capabilities, i.e. flight rate and cost. (In the 1970s, they would have laughed at the idea of a six-month delay in launching a servicing mission.) The Hubble was also beset by requirements that they borrow tech from the military spysat side, but without classified knowledge about the limitations of that tech. The closed procurement process probably factored in the misshapen mirror.
But it is also crystal-clear from the book that NASA fumbled the PR. First they dissembled about the problems, then they labeled it a complete failure. Chaisson and others desperately tried to show that it could do real science even with the astigmatism, and they succeeded. And they came up with a correction, and NASA got on board with installing the fix. Since the fix, it has performed at or above expectations.
The gyros were known to have a limited lifespan, and having them replaced was always a possibility. The telescope is happily waiting in safe mode for its systems to be repaired. The shuttle repair mission was moved up, but then it was held, and held, and held again, while the gyros began to fail. Having Hubble offline is extremely disappointing, but this particular problem is really not to be compared with a design flaw. In fact, with this mission and the 3B repair mission in '01, we can probably expect Hubble to outperform its expected 15-year on-orbit lifespan.
(If anyone can recommend a decent book from outside Chaisson's perspective, I'd like to hear of it, just to hear the other side of the story.) ----
-- lake effect weblog {Network engineer in Chicago--looking for work!}
The Hubble was also beset by requirements that they borrow tech from the military spysat side, but without classified knowledge about the limitations of that tech. The closed procurement process probably factored in the misshapen mirror.
It most certainly did. The mirror on the Hubble was built by Perkin-Elmer, in a plant devoted to spysats. NASA was not allowed access to the plant to verify the correct figuring of the mirror, and an error by P-E in the construction of the test gear caused it to be built to an incorrect focus. As a cost-saving measure, the entire Hubble was not checked for proper focus before launch (Perkin-Elmer was assumed to know what they were doing). In contrast, the backup mirror contract was let to Kodak; after the problem with the P-E mirror was discovered after launch, Kodak's mirror was checked and found to be flawless.
I guess "open-source" isn't just good for software, it's good for space projects too. -- The Karma Century Club is taking new members.
-- Time is Nature's way of keeping everything from happening at once... the bitch.
>>The closed procurement process probably factored in the misshapen mirror. >It most certainly did.
To be sure, Chaisson merely theorizes to that effect. He implies that the NASA officials overseeing the process were not allowed access to the spysat optical tech and were not, in a sense, qualified to check Perkin-Elmer's work.
NASA was not allowed access to the plant to verify the correct figuring of the mirror,
It's not clear to Chaisson (ten years after the fact), but he believes that NASA simply rubber-stamped P-E's own tests, even though they may have shown the error.
As a cost-saving measure, the entire Hubble was not checked for proper focus before launch (Perkin-Elmer was assumed to know what they were doing).
To be clear, this was a result of the lower bid entered by P-E. It wasn't made after the fact. ("Hey, let's not check the mirror.") It may have been an oversight ("Hey, how come this bid's cheaper?"). NASA tried to pump up the testing cost to astronomical levels after the fact, to defend this choice, but Chaisson believes it could have been tested very cheaply. It was simply not considered critical to check the contractor's work on delivery.
In contrast, the backup mirror contract was let to Kodak; after the problem with the P-E mirror was discovered after launch, Kodak's mirror was checked and found to be flawless.
This is incorrect; I just read that chapter. The Kodak mirror was delivered to P-E before they had finished their own mirror. The crate in which it arrived remained on the P-E premises (as of 1991's writing), but nobody could/would verify whether or not it still contained a mirror. It was rumored to have been recycled into a spysat. Chaisson believes that it was probably flawless, since Kodak used a more reliable (standard) process to make it.
So, Kodak delivered a good mirror, but P-E (for some odd reason) had the choice to use their mirror or a competitors. Guess which they went with. ----
-- lake effect weblog {Network engineer in Chicago--looking for work!}
With all the delays that Discovery and the rest of the shuttles have been experiencing, I think it may be time to retire the shuttles in favor of a newer design.
That's pretty disingenuous. What "newer design" is flight-ready? None.
While I'm no fan of the money-sucking, delay-prone, self-perpetuating shuttle program (I'd rather see that money spent on science missions, unless they're going to do something worthwhile like go to Mars), the shuttle is it for now. They're presently testing future shuttle technologies, e.g. X-33 and X-34 testbeds, X-38 flying wing station escape pod (CRV), and the big flying wing project from LockMart called VentureStar (we made it, it's really expensive, please buy it to make us rich). These are steps in the right direction, but they're baby steps. We're nowhere near designing the real next-generation shuttle. In fact, given the fact that shuttle's main apparent problems are not in fact problems -- that is, the people running the show care not about launch costs nor about delays, since the shuttle has so little to do nowadays -- it's hard to argue that it needs replacement.
There is a slate of possible shuttle upgrades, but again, they tend to solve problems we don't actually have (i.e. nobody cares about): making launches cheaper, or faster, or more capable. These would be nice to have, but there is no mission that requires them.
Meanwhile, the commercial launch business is sprinting toward next-generation vehicles like Rotary Rocket that have a good shot at reducing launch costs dramatically, which will change the equation for putting satellites in orbit -- and maybe just turn NASA into an agency buying a transport-to-orbit service from the market. ----
-- lake effect weblog {Network engineer in Chicago--looking for work!}
LOL! I have the 300kbps NASA TV stream running here at work. They were printing the "morning mail" on Discovery. They have a laptop apparently running Windows, hooked up to a Thermal Impact printer. They apparently have a pretty nice setup, nicer than I would have expected. They can do colour or black and white print-outs, they have MS Office, etc.
They get daily messages sent up from Mission Control with data and instructions, checklist changes, etc for the upcoming day's activities. I wonder if it's a standard email system with a TCP/IP stack on the laptop, or if it's some shuttle specific protocol?
Well anyway, they apparently had a paper jam in the printer this morning. I had a good chuckle as I listened to the conversation between CAPCOM Chris Hadfield and John Grunsfeld in orbit as he fixed it. He was opening documents in MS Word and printing out single pages, describing garble characters, pagination problems, etc. It was neat to hear them talking about this stuff that a lot of us have dealt with in luser support. They were talking about computer stuff in Astronaut terminology.
Chips with smaller feature sizes are usually more susceptible to radiation. Space qualified, radiation hardened chips are often several generations behind commercial chips. Most vendors have bailed out of the milspec/space market. The profits (if any) are too small in comparison to the commercial market. ESA designed a space qualified version of the SPARC and Sandia National Laboratory is working on a space qualified Pentium.
This is listed as STS 103, but the NASA guy during the lift-off yesterday mentioned this as being the 96th flight of the shuttle program. Where are the other 7?
Shuttle flights are numbered in the order that the missions are planned. The shuttle schedule gets moved around for all sorts of reasons, from weather in Kazakhstan to wiring problems to wacked-out gyroscopes in orbit. It would be confusing to change the numbers around to match the actual launch order.
The big gap is unusual, mainly because about a dozen International Space Station missions, that have to be done in a certain order, are all waiting on the Russians to launch the Service Module.
Consider that the STS-103 numbering scheme is an improvement over the cryptic "STS-61C" scheme they briefly used in the 1980s: first digit=year, second digit=launch site (1=KSC, 2=Vandenberg), final character=order scheduled in year. And even those would get mixed around. ----
-- lake effect weblog {Network engineer in Chicago--looking for work!}
The embarassing thing about the Hubble is, as Scientific American pointed out some years back, is that one repair mission costs more than all the currently proposed ground-based telescope projects. A few new state-of-the-art ground-based telescopes would both more useful to astronomers and much cheaper, they reported. And they were complaining about the first repair mission.
So it's a pork program.
The basic problem with space travel, of course, is that chemical fuels just don't have enough energy to do the job right. So all space vehicles are mostly fuel, and all flight hardware has to be weight-reduced unreasonably, resulting in tiny payloads and expensive, fragile systems. This is why space travel hasn't made much progress since the 1960s. (The Shuttle, remember, is a 1960s design.)
None of the alternatives to chemical fuels look good. Nuclear propulsion would work, but it's messy. Antimatter looks possible but dangerous. Beanstalks are beyond current technology. The NASA program on alternative propulsion hasn't come up with much. (Links to this seem to be down during the renaming of NASA Lewis to NASA Glenn.) Laser propulsion was considered seriously around 1980 but seems to have been dropped. So we're stuck with chemical fuels until somebody has a really good new idea.
Someone mentioned Rotary Rocket. That's a cute idea, but like all single-stage-to-orbit vehicles has a very tight weight budget. In fact, since they had to back off on the rotary engine and went with an off-the-shelf design, their vehicle will not be able to reach orbit. Almost, though.
Well seeing the space shuttle take off from 300 miles away is a religious experience. First you see the cirrus clouds way of in the distance get faint red, then you see a huge ball of fire rise right under the red clouds, illuminating them from underneath and arcing to the right. Then it punches through the clouds, flares up, and spits out two smaller balls of fire, the boosters. The white ball of fire produced by the main engines keeps burning forever and arcs right until it looks horizontal but really you're seeing the curvature of the earth. Then it becomes just another star, like Battlestar Galactica. I got the whole thing on Realvideo. It's extremely rare to get a perfectly clear night in Fl*rida in December.
Then how can it be a bad design? It may not fulfill the initial design vision...
You just answered your own question. If you design something that doesn't do what it was supposed to do, no matter how well it does something else, then it is a bad design.
You didn't show the rest of the post in which I said that 'visions change'. Quake III was just released. If you look at the original screenshots from way back when, you see a lot of curved surfaces, undulating walls, and really cool character faces. The levels that were released with the final version weren't anything like these screenshots. They changed the way they designed those levels because of the way those levels impacted computer systems. Was the final design a bad design? No. Did it fulfill their goals? Yes, or so they say. Did it fulfill the initial design vision? No. And things rarely do. That's the great thing about the design process. Things change as you move through it.
I think in the mid 70s, the idea of the space shuttle was a great one and the initial vision was a perfect one, but the technology didn't exist then to actually create a machine that would do everything that they wanted it to do. So they chose the things they really wanted (people in orbit, reusable, big payload) and trimmed out the things they wanted (speed, cheapness) and modified the design goals. If we tried to do the space shuttle's initial design today, I think we would get a lot closer to those original goals, but I think that NASA, even from the outset, has been about public relations, and there's no way they are going to satisfy themselves with general aviation requirements for a vehicle that carries people into outer space. If you want that kind of safety, you are not going to get a two-week turnaround on spacecraft. It just won't happen.
I attended a lecture by Constance Adams, the chief architect for NASA (she designs the habitation modules for the space station, as one of her duties). She said that NASA, unlike other organizations, has zero tolerance for failure. Every system is designed not to fail. They're not designed just to do their job, but they're also designed not to fail (and she made the distinction). Furthermore, systems are designed to handle failure within their systems so that if a failure does happen (and remember, they have zero tolerance for failure), then those part won't fail. That kind of redundancy takes time to ensure. The space shuttle is by no means 'experimental technology'. It was tested many many many times before it ever even made it's way up to the launch pad. It's still tested many many many times before every launch. Just because something is one-of-a-kind does not make it experimental. NASA was more positive of the outcome of its first shuttle launch than you are of your car.
But I digress. Back to the original comment, yes, the shuttle is a bad design for the inital design vision, but that's not what it was designed for. It was designed for a highly modified (some might say compromised) design that you see fulfilled every time a shuttle makes it safely to and from orbit. Yes, we need a new orbiter system and we'll get it. NASA wants it more than you or I. But NASA also realizes the incredible value and stability of its current system and chastising that system is simply ignoring its incredible success.
Slashdot Mirror
Under the link to the crew is a list of what they're having to eat. It seems that Curtis Brown is having Rehydratable Shrimp Cocktails for both lunch and dinner today! Must be nice. :)
After reading these menus, I'm pretty hungry... I think I'll go grab a donut. :^)
"I have never let my schooling interfere with my education." - Mark Twain
Does anyone know if the sort of problems the Hubble is having are "routine"
Yeah; they're routine. The telescope was designed to be upgradable and reparable, and the gyroscopes -- the main problem -- have lasted longer than was originally anticipated.
It was never a question of if the gyroscopes would fail, but when.
As for beset by problems: okay, the focus thing when it first went up was unfortunate and expensive, but since then, its problems were those of any satellite with a shitload of different technologies aboard. Its original aim -- to spot extra solor planets -- has never been achieved, but it's been a stunning success in every other regard.
I for one don't trust the shuttle to be in the air in 11 days time.
Don't worry, neither does NASA. They said they'd cut one "EVA" (spacewalk) which would have covered some peeling paint(!) on rails around the telescope, in order to get back in time for Y2K. They're concentrating on replacing the 6 gyroscopes this time, according to the local talking heads on TV.
I saw the launch live last night (I live in Melbourne, FL) and it was lovely. No matter how you feel about the government's space program (I'm ambivalent-to-negative on it, much as I'm a fan of space exploration in general) a night launch from the Cape is a beautiful sight.
JMR
Try e-gold - (contact me). I'm NOT e-
"Mike broke the Hubble, Mike broke the Hubble"
-MST3k (The Movie)
Yeah all the coverage makes it sound like the thing is falling apart. These reporters must be of the mind that when you buy a car, it's already got oil in it, why would you have to change it? Just wastes more of my/taxpayers money. Chuckleheads...
Blar.
The big secret that nobody at NASA wants to tell anyone is that it wasn't really the Gyroscopes that failed. Some technician dropped his ham sandwich into the optical relay and ever since launch the cheese in it has been heating up and cooling down, thus forming a thin layer of cheese across the mirror. This is why we get all those stunning colorful shots with a yellow tint. The observatories were obviously annoyed so they sent up the shuttle to recover the ham sandwich.
Pity none with equal capabilities is available right now or even in sight... Even without a requirement for cutting launch costs!
What about Rotary Rocket ?
Contrary to the popular belief, there indeed is no God.
"Except that I read somewhere that, unofficially, the shuttles' software has never been able to handle a year change correctly, anyway..." You are right, the software cannot handle a year-end rollover. The navigation routines that tell the orbiter where to de-orbit perform their calculations in the M50 (Mean of Aries 1950) coordinate system. This system is an inertial coordinate system, which means that it is referenced to a fixed point in space. Now, in order to deorbit into the right window, we need to tell the orbiter how the earth is positioned within this inertial reference frame. To accomplish this we need to use a Rotation Nutation Precession (RNP) matrix to transform the orbiter's position in M50 coordinates to a position in Earth Centered Earth Fixed (ECEF) coordinates. The RNP matrices are computed on the ground for various times during the year and each are only good for about 3-months on either side of their designed time. If a launch slips over the year end, the RNP matrix is no longer any good, no matter how stale it is (1 day or 1 month or [1 year - 1 hour]). The good news is that we have now designed an improvement to the flight software that calculates the RNP matrix on-board. This would be able to get us out of this predicament, but I would venture to guess that the program still would never have a mission that would cross the year-end boundary in orbit. Actually, we could probably get out of it by patching a new RNP while in orbit, but that is a risk that the program is most likely unwilling to take. - These views are mine and do not necessarily represent those of my employer.
That's a Galileo project picture. Some Hubble shots are available at http://marvel.stsci.edu/top.html.
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The Karma Century Club is taking new members.
Time is Nature's way of keeping everything from happening at once... the bitch.
Kinda worrying that NASA aren't so confident about their Y2K readiness. Guess you have to be when you're so much in the public eye. But what happens if they have some other non-Y2K problems that hold them up further ... into the new millenium?
Regards, Ralph.
It's not just a function of old age. The two major delays this mission were to check the wiring (after finding faulty wiring on another shuttle) which is purely a safety consideration and to repair a dented pipe, which was probably caused by a freak occurence. These are problems which could strike any space mission, new or old, and doesn't really have anything to do with the age of our shuttle fleet.
Granted, the shuttles are old, but these delays are simply the result of the Challenger incident and NASA's goal to keep people alive. The shuttles themselves are probably in better shape than your current car, and they're certainly in better shape than any car you've owned for 20 years.
Of course, I'm not saying that a newer design isn't warranted (and NASA has actively been researching towards that goal), but don't dismiss the shuttles because of the delays. It really isn't 'bad design' that's causing them. I think 20 years from now we'll still be able to use the shuttles, even if it's in a workhouse capacity (see the old Nebula-class starships from Star Trek, ST:TNG, and ST:DSN if you need an example).
Is it really worth it? Hafta ask somebody else, I was just the sysadm for a sister project when the thing went up. Didn't stick around for the results.
Glenn Stone
former Data Validation system administrator
NASA UARS (Georgia Tech)
now under contract to another fine airplane company in the Seattle area
I don't strap my car to two solid rocket boosters and send it into orbit, at least not regularly. This is a very bogus comparison, the tolerances (e.g. heat, stress) required for normal operation of a car, and the tolerances required for a man rated launcher are not comparable.
You also don't baby your car the way that NASA babies it's space shuttles, nor do you meticulously repair the maybe slightly defective parts the way NASA does with the space shuttle. Both vehicles are designed for certain limits, and both operate within those limits.
Unfortunately is bad design thats causing the delays, the shuttle design was a compromise (much like the current ISS debacle) due to repeated budget cuts. Initially design targets were to have something that could fly and turn around again in a matter of days or weeks, they were looking for a shuttle that could fly (at a minimum) twenty or thirty times a year. What they ended up with falls very short of the mark, something that was actually more expensive to launch than a normal rocket. The shuttle is an aging launcher, with design compromises at every turn, it shows.
Compromise of the initial design vision isn't what's delaying the shuttle in any way. If the shuttle was built to be used 20-30 times a year, it still would undergo the safety checks that NASA is giving it now, and if they wiring was bad on one of those shuttles, I'm sure NASA would take the time to check each one, and it would probably still have an excessive number of miles of wiring. What's causing the delay here isn't the design of the shuttles, whatever form that design may be, but NASA's anality (analism, analness?) about safety. Rightly so, I might add, since protecting the lives of the passengers should be the top priority.
Hopefully, VentureStar won't be as big a disappointment, although personally I still think they should have gone with the Delta Clipper (at least they had a working prototype in hardware).
Yeah, and in the meantime, what do you use? The current 'bad design' that's really only failed once in 20 years of usage, right? NASA's not going to make the mistake again of stopping all space flight for development of a launching mechanism when they have a perfectly good one. And given the VentureStar or the Delta Clipper's design snafus, I'm glad they're still researching it.
No way, we've already stretched the design lifetime well beyond the inital estimates.
Then how can it be a bad design? It may not fulfill the initial design vision, but as anyone who's ever worked in design can tell you, the vision changes as you work on a project. The fact that the shuttles have lasted this long with only problems to the launch device, not the orbiter itself, shows exactly how great and durable a design it actually is.
The BBC reports that the mission will be shorter than originally planned since the launch was delayed and the "agency did not want astronauts in space over millennium eve in case of computer problems." Kinda worrying that NASA aren't so confident about their Y2K readiness. Guess you have to be when you're so much in the public eye. But what happens if they have some other non-Y2K problems that hold them up further ... into the new millenium?
It's not a matter of confidence; NASA's primary responsibility isn't showing off their confidence, but the safety of the astronauts. All things considered, having crew on orbit over the new year just isn't a good idea. The risk may be small, but the consequences could be fatal.
Boosting public confidence is the job of agencies like the FAA, which is making a point of having its administrator in flight over the Y2K clock tick (except she keeps getting flights cancelled out from under her, due to low demand).
As for problems not related to Y2K, it's more likely that they would then merely cut the mission short. The chance of an in-flight failure that prevents a return to Earth (e.g. cargo bay door stuck open) is the same as before, and nobody wants to think about that. There simply isn't any contingency for a rescue of a disabled shuttle.
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lake effect weblog
{Network engineer in Chicago--looking for work!}
That sounds a little extreme just because of some launch delays (which have *always* been the norm with the space program). But if you want to look at a commercial reusable launch platform, take a look at this site.
Admit nothing, deny everything and make counter-accusations.
Can anyone tell me why the BBC has better intel on the NASA/shuttle situation than anybody IN the US? It just seems kinda odd that with all the DIRT our local media can dig up why can't they get any REAL inforamtion on what is going on at NASA.
This isn't "intel", it's been publicly announced that they chose to launch Sunday but trim one of the spacewalks (the insulation, which has the lowest priority, will now be part of repair mission 3B in 2001).
It is, however, true that NASA has a set way of dealing with the media, and are notorious for preferring those reporters who will play ball with their PR line. The constituencies within NASA who deviate from the official story are punished or exiled. The NASA public affairs office can be extraordinarily petty (viz. the way they tried to require that all Hubble photography carry only the NASA logo, no matter that the Space Telescope Science Institute prepared it or that European Space Agency equipment was used).
The media, in general, mostly run stories about NASA when they have:
a) a ready-made success story
b) pretty pictures
c) a major failure
c) 1) if major failure within last year, also report all minor failures in ominous tones
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lake effect weblog
{Network engineer in Chicago--looking for work!}
Odd... it seems to me that every time I turn around, Hubble has broken again... are we attacking the symptoms here or the disease, so to speak?
You might want to learn a little more about the Hubble mission. When this thing was put together, several servicing missions were anticipated to replace components as the wore out, and to upgrade or swap out instruments. These missions are planned on a three year cycle.
The ORIGINAL plan was to bring the Hubble back to earth for refitting every 5 years, however the ability of shuttle crews to do in-orbit servicing has made this unnecessary.
IN FACT, the Hubble has been one of the greatest successes of the entire space program.
This mission not only includes replacement of gyroscopes (that lasted longer than originally planned), but upgrading some instruments and the main Hubble computer system.
What they wound up with looked very different from the Space Scuttle and VultureStar. It was a squarish bullet, covered in thermal-blanket material originally developed for the Shuttle. It was not terribly fussy about its engines; it could have flown on J2's or RL-10's. The innovations were several:
- It was designed to land tail first, under power. This takes advantage of the engines, which are along for the ride, to provide landing capabilities. This eliminates the need to be able to glide subsonically; the glideslope, flare and landing maneuver required by Shuttle (and VentureStar) is unnecessary.
- It did not have wings. This saved a great deal of weight in the airframe.
- Its landing gear was a system of struts and pads. No wheels required. This saved more weight.
- The pilot went away also. When so many missions are just putting unmanned birds or cargo in orbit, why carry people along all the time?
The vehicle was to be called the Delta Clipper, or DC-1.The development program was very innovative: build a little, fly the results, roll the lessons learned back into the next generation. The first vehicle (low-altitude atmospheric testing, designed to prove some of the required maneuvers for takeoff, landing and aborts) was the DC-X. The second-generation, subscale, orbital (with no payload) vehicle was to be the DC-Y; it would have tested fuel tankage, weight-saving and thermal-protection systems.
The total cost of DC-X and DC-Y was to be less than one year's budget for the Shuttle program.
SDIO borrowed stuff from everywhere to build DC-X. They got 4 RL-10's on loan from Rocketdyne, had the aeroshell built by Scaled Composites (Burt Rutan's outfit), and reprogrammed an airliner autopilot to fly the bird. DC-X was a phenomenal success, proving everything it was set out to do. And then SDIO, shutting down and getting outside of their bailiwick (which was NOT to develop commercial spacecraft launchers), turned the program and the prototype over to NASA.
NASA completed the scheduled test flights and then crashed and burned the prototype when someone neglected to reconnect a landing-gear unlock line before flight. Accident? Deliberate? No one's talking.
After the destruction of the DC-X, NASA let a contract for the development of a successor to the Shuttle. The developers of the DC-X had a bid in, but the contract was awarded to a company whose vehicle:
- Had no development record;
- Could not be delivered for many years longer;
- Had a much more expensive development program.
On the other hand it took off vertically like Shuttle, landed on (and required) a runway like Shuttle, and required a new engine development program. The winner was not the low bidder. Can you say "more pork"?When the winner of the contract was announced, the counsel for NASA was present. This was apparently to keep the DC-1 proponents from getting the idea of suing to either get the contract or find out what funny business had gone on. In the mean time, the Shuttle and its standing army of maintenance people are still working, and there's a lucrative R&D contract for the VentureStar (even though it's having serious difficulties with its composite LH2 tanks delaminating). It's great for everyone except the taxpayer and people who might benefit from flying satellites cheaper; IOW, it sucks.
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The Karma Century Club is taking new members.
Time is Nature's way of keeping everything from happening at once... the bitch.
Does anyone know if the sort of problems the Hubble is having are "routine" or if this was a problem inherent in the design of the telescope? It seems (and maybe I'm just too influenced by the media) that this project has been beset by problems from the very start. Too bad too...its images are breathtaking.
If you want the whole story, I highly recommend reading Eric Chaisson's The Hubble Wars ; he was a senior scientist on the project during the pre-launch and commissioning, and is a tremendously detailed but engaging scientific writer. Read it, and you'll never look at NASA the same way again. (For a similar perspective on people in space, read Dragonfly.)
The problems with Hubble are too many to enumerate here, but they begin with the overselling of the shuttle's capabilities, i.e. flight rate and cost. (In the 1970s, they would have laughed at the idea of a six-month delay in launching a servicing mission.) The Hubble was also beset by requirements that they borrow tech from the military spysat side, but without classified knowledge about the limitations of that tech. The closed procurement process probably factored in the misshapen mirror.
But it is also crystal-clear from the book that NASA fumbled the PR. First they dissembled about the problems, then they labeled it a complete failure. Chaisson and others desperately tried to show that it could do real science even with the astigmatism, and they succeeded. And they came up with a correction, and NASA got on board with installing the fix. Since the fix, it has performed at or above expectations.
The gyros were known to have a limited lifespan, and having them replaced was always a possibility. The telescope is happily waiting in safe mode for its systems to be repaired. The shuttle repair mission was moved up, but then it was held, and held, and held again, while the gyros began to fail. Having Hubble offline is extremely disappointing, but this particular problem is really not to be compared with a design flaw. In fact, with this mission and the 3B repair mission in '01, we can probably expect Hubble to outperform its expected 15-year on-orbit lifespan.
(If anyone can recommend a decent book from outside Chaisson's perspective, I'd like to hear of it, just to hear the other side of the story.)
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lake effect weblog
{Network engineer in Chicago--looking for work!}
With all the delays that Discovery and the rest of the shuttles have been experiencing, I think it may be time to retire the shuttles in favor of a newer design.
That's pretty disingenuous. What "newer design" is flight-ready? None.
While I'm no fan of the money-sucking, delay-prone, self-perpetuating shuttle program (I'd rather see that money spent on science missions, unless they're going to do something worthwhile like go to Mars), the shuttle is it for now. They're presently testing future shuttle technologies, e.g. X-33 and X-34 testbeds, X-38 flying wing station escape pod (CRV), and the big flying wing project from LockMart called VentureStar (we made it, it's really expensive, please buy it to make us rich). These are steps in the right direction, but they're baby steps. We're nowhere near designing the real next-generation shuttle. In fact, given the fact that shuttle's main apparent problems are not in fact problems -- that is, the people running the show care not about launch costs nor about delays, since the shuttle has so little to do nowadays -- it's hard to argue that it needs replacement.
There is a slate of possible shuttle upgrades, but again, they tend to solve problems we don't actually have (i.e. nobody cares about): making launches cheaper, or faster, or more capable. These would be nice to have, but there is no mission that requires them.
Meanwhile, the commercial launch business is sprinting toward next-generation vehicles like Rotary Rocket that have a good shot at reducing launch costs dramatically, which will change the equation for putting satellites in orbit -- and maybe just turn NASA into an agency buying a transport-to-orbit service from the market.
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lake effect weblog
{Network engineer in Chicago--looking for work!}
LOL! I have the 300kbps NASA TV stream running here at work. They were printing the "morning mail" on Discovery. They have a laptop apparently running Windows, hooked up to a Thermal Impact printer. They apparently have a pretty nice setup, nicer than I would have expected. They can do colour or black and white print-outs, they have MS Office, etc.
They get daily messages sent up from Mission Control with data and instructions, checklist changes, etc for the upcoming day's activities. I wonder if it's a standard email system with a TCP/IP stack on the laptop, or if it's some shuttle specific protocol?
Well anyway, they apparently had a paper jam in the printer this morning. I had a good chuckle as I listened to the conversation between CAPCOM Chris Hadfield and John Grunsfeld in orbit as he fixed it. He was opening documents in MS Word and printing out single pages, describing garble characters, pagination problems, etc. It was neat to hear them talking about this stuff that a lot of us have dealt with in luser support. They were talking about computer stuff in Astronaut terminology.
Chips with smaller feature sizes are usually more susceptible to radiation. Space qualified, radiation hardened chips are often several generations behind commercial chips. Most vendors have bailed out of the milspec/space market. The profits (if any) are too small in comparison to the commercial market. ESA designed a space qualified version of the SPARC and Sandia National Laboratory is working on a space qualified Pentium.
Mea navis aericumbens anguillis abundat
(somewhat off-topic)
This is listed as STS 103, but the NASA guy during the lift-off yesterday mentioned this as being the 96th flight of the shuttle program. Where are the other 7?
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
So it's a pork program.
The basic problem with space travel, of course, is that chemical fuels just don't have enough energy to do the job right. So all space vehicles are mostly fuel, and all flight hardware has to be weight-reduced unreasonably, resulting in tiny payloads and expensive, fragile systems. This is why space travel hasn't made much progress since the 1960s. (The Shuttle, remember, is a 1960s design.)
None of the alternatives to chemical fuels look good. Nuclear propulsion would work, but it's messy. Antimatter looks possible but dangerous. Beanstalks are beyond current technology. The NASA program on alternative propulsion hasn't come up with much. (Links to this seem to be down during the renaming of NASA Lewis to NASA Glenn.) Laser propulsion was considered seriously around 1980 but seems to have been dropped. So we're stuck with chemical fuels until somebody has a really good new idea.
Someone mentioned Rotary Rocket. That's a cute idea, but like all single-stage-to-orbit vehicles has a very tight weight budget. In fact, since they had to back off on the rotary engine and went with an off-the-shelf design, their vehicle will not be able to reach orbit. Almost, though.
And that's the way it is.
Well seeing the space shuttle take off from 300 miles away is a religious experience.
First you see the cirrus clouds way of in the distance get faint red, then you see a huge ball of fire rise right under the red clouds, illuminating them from underneath and arcing to the right. Then it punches through the clouds, flares up, and spits out two smaller balls of fire, the boosters. The white ball of fire produced by the main engines keeps burning forever and arcs right until it looks horizontal but really you're seeing the curvature of the earth. Then it becomes just another star, like Battlestar Galactica. I got the whole thing on Realvideo. It's extremely rare to get a perfectly clear night in Fl*rida in December.
Then how can it be a bad design? It may not fulfill the initial design vision...
You just answered your own question. If you design something that doesn't do what it was supposed to do, no matter how well it does something else, then it is a bad design.
You didn't show the rest of the post in which I said that 'visions change'. Quake III was just released. If you look at the original screenshots from way back when, you see a lot of curved surfaces, undulating walls, and really cool character faces. The levels that were released with the final version weren't anything like these screenshots. They changed the way they designed those levels because of the way those levels impacted computer systems. Was the final design a bad design? No. Did it fulfill their goals? Yes, or so they say. Did it fulfill the initial design vision? No. And things rarely do. That's the great thing about the design process. Things change as you move through it.
I think in the mid 70s, the idea of the space shuttle was a great one and the initial vision was a perfect one, but the technology didn't exist then to actually create a machine that would do everything that they wanted it to do. So they chose the things they really wanted (people in orbit, reusable, big payload) and trimmed out the things they wanted (speed, cheapness) and modified the design goals. If we tried to do the space shuttle's initial design today, I think we would get a lot closer to those original goals, but I think that NASA, even from the outset, has been about public relations, and there's no way they are going to satisfy themselves with general aviation requirements for a vehicle that carries people into outer space. If you want that kind of safety, you are not going to get a two-week turnaround on spacecraft. It just won't happen.
I attended a lecture by Constance Adams, the chief architect for NASA (she designs the habitation modules for the space station, as one of her duties). She said that NASA, unlike other organizations, has zero tolerance for failure. Every system is designed not to fail. They're not designed just to do their job, but they're also designed not to fail (and she made the distinction). Furthermore, systems are designed to handle failure within their systems so that if a failure does happen (and remember, they have zero tolerance for failure), then those part won't fail. That kind of redundancy takes time to ensure. The space shuttle is by no means 'experimental technology'. It was tested many many many times before it ever even made it's way up to the launch pad. It's still tested many many many times before every launch. Just because something is one-of-a-kind does not make it experimental. NASA was more positive of the outcome of its first shuttle launch than you are of your car.
But I digress. Back to the original comment, yes, the shuttle is a bad design for the inital design vision, but that's not what it was designed for. It was designed for a highly modified (some might say compromised) design that you see fulfilled every time a shuttle makes it safely to and from orbit. Yes, we need a new orbiter system and we'll get it. NASA wants it more than you or I. But NASA also realizes the incredible value and stability of its current system and chastising that system is simply ignoring its incredible success.