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Clock Ticking for Hubble
DoraLives writes "Ok then, what are we going to do with Hubble? Eventually, it MUST come down. The New York Times has a piece that addresses this less than pleasant (at least for the astronomical community) subject. Additionally "The decision about what happens then has been complicated by the breakup of the Columbia." Read all about it."
Why would that complicate things? All the incident proved was what we know already. Besides, Hubble's done some great things, and of course it'll have to come down eventually. We just have to move on and produce a successor.
Bash script for FP whores
Why not just shove it into a bit higher orbit?
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Of course, Taco Bell will put a big floating bullseye in the ocean and if some titanium part of hubble hits it everyone in the US wins a Taco!
Wooo Hoooo!
Why don't we get some other country
to foot the bill on boosting it
into a sustainable orbit and paying
for the initial maintenance after
2010. I'm sure that an India or
Taiwan would be willing to take it on
for less than $500 million.
Click here
Reality has a liberal bias
Not that 're-deployment' would be easy, mind you, but unless there's some kind of fuel issue, I don't see why it wouldn't be possible (bearing in mind I'm far from an expert on the subject).
On one hand, it would develop skills for astronauts that would be needed on the Space Stations, on the other, it's not cheap and doesn't provide advancement in deployed equipment.
Then again, maybe in 50 years, retrofitting sattelites for technology upgrades by Space Station personnel might become a regular thing.
"Gotta do an EVA to install an upgrade on the Hubble, back in about half an hour. Want me to pick up anything while I'm out?"
No way! Then you run the risk of Paramount taking William Shatner out of drydock.
And they'll shoot more "extra" footage that is really really really dull.
NASA has long planned to end Hubble's spectacular run and bring it down in 2010 to make way in the budget for the James Webb Space Telescope, scheduled to be launched in 2011.
Theres a gap there in time where we wont have a telescope up there. this will be the end of the world, as we wont be able to see the asteroid comming at earth in time to send our best deep crust drillers to drop a nuke in it and split it up!
If sending up a Shuttle to re-establish a fresh orbit for Hubble would be cheaper than building a new and improved Hubble and launching it?
Development cost of Hubble: $2 billion
Cost of one space shuttle launch: $600 million
So you can get in excess of three launches for the same cost of the Hubble.
Toronto-area transit rider? Rate your ride.
I just find is pathetic that the U.S. can't find $600m to refurb the HST. We're spending about twice that EVERY DAY on operations in Iraq.
Just pull the troops out two days earlier and there you have it... enough cash to service the Hubble twice!
My opinion is that the HST should be retrofitted with a small nuclear power source (like those on the Voyager series) and send out of the solar system. But unlike previous missions were the probes were sent past the outer planets, we should send HST perpendicular to the Earth's orbit, so we can look back "down" on ourselves and surrounding stars/planets.
I can't recall if the solar system plane is about parallel to the galactic plane, but if so this would also give us a tremendous perspective on the galaxy that we haven'y had before. Yea, yea it would take a decade or two to get to a distance that would mean anything astronomically, but it has to happen some time, why not now.
Article X: The powers not delegated... by the Constitution...are reserved...to the people
Hubble is in Low Earth Orbit (LEO). It's got an orbital velocity of around 4KM/Sec.
To raise the orbit far enough to get to the Moon, takes a total deltaV of 7KM/S (or another 3KM/S on it's current speed).
The Earth orbits the sun at around 30KM/S, give or take. So to send something - anything - into the sun requires a deltaV of the same amount: you've got to cancel out the existing 30KM/Sec velocity, otherwise you're just going to send the object into a different orbit around the sun
The fastest any object has left the earth is around 8KM/S for the interplanetary probes (Pioneer, Voyager, Cassini, Galileo etc). That's as fast as the human race has ever gotten anything going[*]. Without a major advance in rocket technology (i.e. away from chemical rockets), that's about as fast as we're going to get anything going, too.
As a reference, the on-orbit manoever capability of the Shuttle, is a total of about 100M/S
Oh, and Hubble has much MUCH less manoever capability than this
This is why things are de-orbited, rather than "sent towards the sun" or further out. De-orbiting from LEO requires only a little "kiss" of deceleration before the orbit intersects the atmosphere, from where friction does the rest. The only exceptions are Satellites in higher orbits (e.g. GPS in the 12-hr / 12,000KM orbits, or Geostationary sats) which tend to be "retired" in slightly higher orbits because these are thought to be more stable over longer (geological) time periods than lower ones, and there's not enough residual manoever capability to lower the orbit enough to graze the atmosphere
[*] = However, we've learnt the trick of gravitational assists which lets Mother Nature (or Newton, or Einstein depending on your religious orientation :-) speed up our probes considerably at the expense of the orbital energy of the planet we're assisting from.
--
I'd rather have a bottle in front of me than a frontal lobotomy
I've been an avid avid amateur telescope maker since I was twelve years old. It led to me studying astronomy for a time at Caltech. While I'm a programmer now, it's still a very enjoyable and intellectually stimulating hobby.
While a basic newtonian is a straightforward instrument that can be built by anyone who's good with their hands, telescope making can get as complicated as you want if you're really looking for a challenge. Optical design is still a wide open area of research in mathematics, software engineering, and physics, and some of the more interesting designs take quite a bit of skill to fabricate. That means anyone can make a satisfying telescope, but the hobby will yield a lifetime of interest because there's always new things to learn.
You can construct your own telescope with a primary mirror of 8 inches in diameter for less than $200. It will take quite a bit of work, but it is enjoyable and meditative work. Grinding mirrors is one of the things I do to relax and relieve the strain of coding all day.
A good place to start looking for information is the ATM FAQ. The procedures for grinding, polishing and figuring are pretty involved - you should buy one of the books from astronomy publisher Willman-Bell.
There are a number of people and business who sell inexpensive mirror grinding kits. They will come with a glass mirror blank and an assortment of different sizes of abrasive grits. I would recommend asking on the ATM mailing list (that you can find in the FAQ) when you're ready to order your first kit.
The 8" plate glass kit I bought from Dan Cassaro for my current project set me back $64. When I get done working on the mirror, it will cost me about $35 to have a vacuum coating laboratory aluminize it. Good quality eyepieces cost about $50 - just one will do to start with but it helps to have more.
While fancy equatorial mountings can be expensive to make, it's possible to make a quite servicable altazimuth mount out of common materials like plywood and a few hand tools.
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I'm certain that it would have brain-dead simple to convince GM or Ford or DuPont to spend billions of dollars to build, launch, and maintain something which produces pictures of objects in space. In fact, I seem to recall that NASA had to sue a number of such companies to keep them from launching several other pure science satellites which had no commercial value. Stockholders in those companies were outraged that the attempts of their management to dump billions of dollars into altruistic enterprises were thwarted by evil bureaucrats. Idiot. Get a clue as to what private companies do and why and how they do it.
Hubble was designed to be serviced, on-orbit, by the Shuttle. This is '70s NASA remember which was juust getting the hang of perpetually self-justifying programs. Why do we need a Shuttle? To service Hubble, of course! Ahh, but why do we need Hubble? To give the Shuttle something to do!
Rather less cynically, note that the design life[*] of most unattended satellites is 5 years. After that period of time, enough is going to have started going wrong (fading power from radiation and micro-meteorite damaged solar cells is the classic example) that it's just not worth adding extra redundancy into the design up front to cover it (remember that redundancy = mass consumed that can't be used for the primary purpose of the sat.). Hubble has been up nearly 15 years now, and still has 5 years of useful life in it. That's because all of the things that traditionally go wrong - see the solar cells - have been replaced at least once. Also note that not only was the critical design-flaw in the mirror corrected on-orbit by the first Shuttle service mission (turning what would have been a wasted sat. requiring complete replacement and relaunch into a fully-functioning success), but later service missions have replaced components with improved versions, increasing the capabilities of Hubble enormously. It's like there's been 3 Space Telescopes up there, for the cost of... well, let's not go there. NASA's more than capable of making it look like it's cost less than 3 complete new telescopes, I'm sure...
[*] = as opposed to the actual life which can be much longer, but can't be predicted in advance
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I'd rather have a bottle in front of me than a frontal lobotomy
We spent so much time, money and effort fixing it, why not spend some more and upgrade it for another decade of use?
Same reason many people will junk an old car which they've spent lots of time, money, and effort fixing. It's nearly the same cost to just buy a new one as to fix the old one, and the new one comes with more features.
For everything Hubble has done to further astronomy (and since it was practically the only bright spot of the otherwise maligned space program), they owe it a better end than what they are proposing. To deorbit it and let it burn up with as much thought as one would give to flushing a dead goldfish is just plain wrong.
It should definitely be retrieved and become a piece in the Air & Space Museum's collection.
Drastic and sorry failures? Do you have any evidence to back your claims that all of these programs are failures?
Let us imagine for a moment what things would be like without public education.
For one, a lot of children would receive *no* education. Either because their parents could not afford it, or because their parents did not believe that education is a necessary component of a democratic society.
Secondly, many high school graduates (of private high schools) would not be able to attend college. Even public college tuition is expensive these days.
Another interesting thing about publicly funded research is that it benefits everyone. The goal of publicly funded programs is to benefit our society as a whole. The goal of privately funded programs is to make money for the company. If something isn't ultimately profitable, it won't get funded, even if it is beneficial in other ways.
The moon race isn't the only example, SSI, public education, medicade/medicare are all drastic and sorry failures.
Yeah, not like the shining examples of Amtrak, Worldcom, and Enron.
> I was just thinking, what happened to the space program is a classic example of why it's better for things to be privatized. I mean, one of the worst possible things that can happen to a government program is
I find myself wondering whether you've every had a job. Surely even the most casual observation reveals that private enterprise doesn't have all the magical properties commonly attributed to it. Failed or discontinued projects in the private sector are a dime a dozen, as are pet projects that get funded on the basis of which manager is the best suck-up rather than on the basis of which best satisfies some other requirement (even if that requirement has no higher social goals than raking more gold into corporate coffers). Waste and "dumbsizing" of good projects seem to be the rule in the private sector as much as in the public sector; you're just less likely to see them in the news or hear them harped on for political exploitation by radio talkjox.
Sheesh, evil *and* a jerk. -- Jade
Hubble is an overgrown version of a digital camera. As CCDs improve, you eventually want to replace the ones up there with better ones. This has already been done a couple of times, but electronics keeps improving.
It also has batteries and solar cells that provide power, and these wear out and have to be replaced.
Hubble needs to point itself at things, and it does so using heavy spinning rotors, which are
turned one way, and by Newton's Law, Hubble
turns the other way. There are 5 of these
"Control Moment Gyros", or CMGs. Being mechanical devices, they wear out and break over time.
You need 3 out of 5 to be working to point Hubble, and if they have an MTBF of 12.5 years (which is pretty good for a mechanical device), then you need to visit every 5 years and replace 2 to keep Hubble running.
Hubble has no propulsion and you don't want any until you are ready to kill it. Fluids sloshing in tanks will mess up your pointing of the telescope, and any exhaust from a rocket will contaminate the optical surfaces. When the Shuttle visits, the thrusters are 50-75 feet away, which is much less of a problem than if your booster pack is on the back end of the telescope only 2 feet from the science instruments.
And yes, IAARS, in fact the first group I worked at at Boeing back in 1981 supplied the graphite/epoxy frame that holds Hubble's mirrors in place.
Daniel
Sure hubble has done great things for astronomy but it is just a hunk of metal (and other materials).
I am sure that I still have my first computer somewhere in the loft but that didn't cost me $600 M to keep.
Wouldn't be much better and more respectfull to the exsisting peice of metal to spend the money you would use preserving it to build a bigger better teliscope. (what happened to the idea of building arrays of teliscopes in orbit?)
A lot of the things in the air and space museam are replicas anyway, one more won't hurt.
Maybe it's time for the US to test some of their cool new weaponry. They must have SOMETHING neat that was designed to take out high altitude stuff. What better chance to prove it's effectiveness? I mean, the Hubble has to come down anyway, so why not give us all a show?
They need to just point the Hubble back to earth and create the worlds best voyeur porn site. They could fund all their other missions with that money.
Why not rename it the Hubbard Space Telescope? Then you can get Hollywood Scientology types to pay big bucks to keep it in the air.
`which fortune`
For the same reason you don't put an 80GB ATA133 in that old 486.
Sometimes it's better to just to get a new machine.
It *will* be sad when Hubbble burns up. (And don't think that it's ever going to come down nicely. That opportunity was lost with Columbia as others have pointed out.)
If you don't want to repeat the past, stop living in it.
Off by a factor of two, give or take. 8 km/sec for a typical LEO velocity would be better.
The Earth orbits the sun at around 30KM/S, give or take.
This one's right where it ought to be.
The fastest any object has left the earth is around 8KM/S for the interplanetary probes
8 miles per second it is. Chalk it up to a conversion error.
Otherwise your post is on the money. Yeah yeah, I know I know, it's a damnable bit of persnickityness, but no sense in giving folks bad numbers when good ones are just as cheap, eh?
Is it fascism yet?
There is a ton of debris in space, there is no reason to bring all of that down
Actually, there is. It's a hazard to satellites and orbiting spacecraft. A few years back, one of the shuttles had a small crater made in its windshield when it was hit by an orbiting *paint chip*.
There's just so much space junk and it's moving so fast, that it's tough if not impossible to safely intercept and capture. NORAD actually tracks and catalogs every piece of it large enough to get a radar return. When a shuttle is up, they constantly monitor its path for errant debris so it can maneuver if necessary. I believe they do the same for the ISS.
~Philly
I haven't seen this suggestion here, maybe I missed it.
The HST does have attitude control jets. Generally those are used just to rotate the HST in various axes. They could be reprogrammed to thrust in pairs on the same side of the system, and thus accelerate rather than rotate it. This would slightly alter the orbit each time. Done at the proper points in the orbit it could gradually 'leapfrog' into a higher orbit with minimal effect on the system or usage.
This would take much more thruster fuel than it presently carries, so on the next Shuttle visit, they could bring a larger fuel tank and adapters to mount it to the HST. (They might even be able to develop a remote refueling port that could be used by a robotic tender, but that's more complicated.) This would require some research on how to do so without unduly disturbing the center of mass and reprogramming to deal with the different moment of inertia, but it seems not much more complicated than things they've done before like replacing the mirror, or doing the upgrade a couple of years ago. I think (but I'm not an astronomer) that in between thrust events most observations could continue with updated ephemera.
Another way would be to add a small ion thruster and reaction 'fuel' to the end of the HST and use a small continuous thrust to move it to higher orbit - perhaps even to one of the LaGrange points (L5?). This method would make many types of observations difficult during the entire thrust period of perhaps a year. I speculate that the solar panels would provide enough electrical power to drive the ion thruster(s).
Either of these methods would be stressing the HST at the same order of magnitude as the existing stabilization systems, and it would seem to me that engineering either of these mods is doable in the time frame for the next Shuttle visit, thereby avoiding a separate, expensive visit.
While the Web telescope is anticipated to be much better, there are good reasons to have HST still available. The fact that it is such a piece of science history, I would dearly like to see it moved to a place where it is safe from total destruction, like one of the LaGrange points. It might even become a popular sightseeing "flyby" for tourists on the way to the moon. There it could rest and continue to be used until a means of, for example, safely bringing it down to a museum on the moon could be developed in 50 years or so. Letting it burn up in the atmosphere would be too bad.
It's easier to be a result of the past, but more fun to be a cause of the future! http://www.spacefinancegroup.com/
It's actually worse than that. Orbits at altitudes reachable by the Shuttle decay rapidly, because the atmosphere's a little too thick up there - satellites like the Hubble, with big solar arrays, are particularly vulnerable.
The most important thing that happens on Hubble servicing missions has nothing to do with fixing hardware. The Shuttle catches the Hubble, then fires its maneuvering engines and carries the Hubble up to a higher orbit.
I know this because my company did some computer modeling for NASA to help them predict how often these reboosts would be needed. The amount of atmospheric drag varies with sunspot activity - increased solar output makes the atmosphere "puff up" and makes orbits decay faster.
And guess what? The Space Station is in an orbit reachable by the Shuttle, and also has big solar panels, so it needs reboosting by the Shuttle too.
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-AD