I agree that in hindsight, we would have been better off just lunching 'disposable' telescopes and not spending the money on repairing Hubble. However, with no projected replacement for Hubble anythime in the next 10+ years (the Webb IR telescope only replaces part of the Hubble's functionality), we should commit to one last servicing mission. If for no other reason, we have to send something up to deorbit Hubble in a controlled manner. Once the gyros go out and Hubble starts tumbling, we're screwed - we can't repair it or control its deorbit at that point. It's big enough to cause damage on the ground and it passes over highly populated areas.
Plus, Adaptive ground optics cannot replace Hubbble - they can only view the sky in a very narrow field of view near a bright guidea star to properly controll the optics. Also, you can't do IR or US spectroscopy with ground based instruments, no matter how advanced they get because of atmospheric absorbtion.
I agree that we shouldn't keep dupming money into Hubble forever but the SM4 repair mission is cheap in comparison to the ISS (2% of the ISS shuttle budget alone) and will prevent a huge loss of space-based telescope capabilites. We've ready already sunk a ton of money into Hubble, this one last bit will give us a much improved instrument that will last at least an additional 6 years. Personally, the cost-to benefit is too good to not repair Hubble. Once the Webb goes up, we can lose Hubble without it being TOO painful to the astronomy community but that won't happen until 2012 at the earliest.
Congratulations, you just once again demonstrated that you don't know what you're talking about.
The original wavelengths ARE known. Every piece of observation evidence ever collected supports the idea that the laws of physics that regulate spectral emission have not changed at any point in the visible history of the universe. Those spectral lines are very well known and very accurate. By looking how a particular hydrogen line has redshifted, you immediately know what the redshift is to a great deal of accuracy. The uncertainty has been determining the distance to an object. Unless you have something like a class 1a supernova to use as an absolute distance gauge, you know the object's speed but not distance. The determination of an accurate Hubble constant require both values.
Again, the dark era is pretty damned certain. We know that the universe is expanding away from us. This implies that the visible matter of the universe was once much more compact and dense. Therefore, it simply a matter of back extrapolation to calculate the density of the matter at a given point in time. The dark era is simply when the density of matter would have caused enough light-matter interaction to ionize bulk interstellar gas, making it impermeable to light. There is nothing controversial or speculative about this - the microwave background radiation we can observe is a direct image of this plasma. Optical observations haven't been able to see back to that point yet but we're getting close.
I guess that if you posit that the Big Bang didn't happen and that the universe isn't expanding that it is possible the dark era didn't happen but otherwise, it is a forgone conclusion. There are still some theories like 'lazy light' and alternate gravitational behaviour that are competitors to the Big Bang but they are matching actual data even more poorly as time goes along. Mostly, astrophysicists argue over details on the Big Bang theory these days. Very little serious effort is given to alternate theories since the Big Bang theory fits the data so much better than everything else.
Also, you've completely missed my point. We aren't sitting around and looking at pretty pictures - this is serious science, some of which - like studying interstellar plasma behavior may have practical benefits to building the very space infrastructure you talk about. Cancelling the Hubble will have almost no positive effect upon building a space infrastructure but it WILL have a major negative effect on scientific studies.
I wholeheartedly support robotic and manned missions to Mars and other planets to get hands on sample to work with. However, we have learned FAR more about the solar system and the universe and physics from remote observational tools like Hubble than all the the planetary landers and moon landings put together. Hell, most of the data we have on Mars comes from remote imaging just like what Hubble does.
Further, insisting upon some nebulous, huge space infrastructure is necessary to get to Mars is false. The Mars Direct plan by Zubrin, while having some flaws, demonstrates that you need little to no infrastructure to get to Mars. Big lunar mines make no sense in terms of orbital energetics. It's as if the settlers of the old West had waited for the US government to build a freeway system to be built before heading out. IF that had been the case, the US would still be stranded at the Mississippi river and the native Americans would probably have been much better happier.
If we want to go to Mars, we should go to Mars. If we want to build space telescopes, we should build htem on the ground and launch them. If we just go to Mars and start making colonies, we will eventually build the space infrastructure you talk about as it becomes necessary. There is no way that taxpayers will invest in the infrastructure first and then go - the Shuttle is a prime example of what happens when you start working that way.
Even worse, without the Hubble SM4 repair missions, the Hubble could be non-operation as soon as this year. They're hoping to stretch it out to 2007 but that still leaves a *5* year gap with no wide field UV/optical/IR telescope. The SM4 mission is supposed to get the Hubble running out to 2010 which would allow it to overlap the Webb telescope if we're careful. The Webb isn't a good Hubble replacement but better than nothing. As far as replacing the UV/visible cabailities of the Hubble, a replacement telescope isn't even on the *drawing board* yet.
To make things even better, when the Hubble loses control, it will start tunbmling and basically make repairs impossible. Furthermore, at that point, we won't be able to control the Hubble deorbit. The Hubble is big enough to have large pieces of debris hit the ground and the orbital plane goes over some densely populated areas. So, unless we want to play 'Pin the Hubble on the City', we've got to send SOMETHING up to bring it out of orbit in a controlled manner.
Helpful hint: before making authoritative posts about scientific matters please ensure that you have half a clue about said scientific subject first.
Fission and fusion are perfectly well understood. The fundamentals involved were well hammered out by the late 40's. The experimental observation of the particles involved was done by the late 60's and if you want to be stickler and insist on getting wierd, exotic particles like the W, then we've had fission and fusion completely nailed down for 20 years now.
The reason that we don't have controllable fusion power has nothing to do with understanding the fusion process. Plasma instabilities caused by the interaction of the plasma's own magnetic fields with the containment field cause the reaction to be unstable and die out. Ironically, observations of space-based plasmas done with instruments like the Hubble have proved and are proving quite useful in getting these plasma instabilities under control.
As far as practicality, there are presently NO practical applications for the stuff that particle accelerators have done in the last 40 years or so. It is pure and basic research at its best. Of course, there's the hope that this research will lead to a better unified field theory which could have substantial spin-off applications but so far, this has not been the case. Virtually all of the modern technology we use came from high energy physics research done before 1950. Most of it came from research done before 1930 - the research up to that point was enough to invent quantum physics as most engineers know it.
And finally, your comment about fuzzy blobs in the sky is so monumentally asinine and moronic, I'm not certain how to even respond. The observation and formation and testing of hypotheses is EXACTLY WHAT SCIENCE *IS*!
While the parent was kinda... well, lame, at least the poster was cool about it. It's a seriously posed question and doesn't deserve to be modded as a troll.
To answer the question, here are the tangible Hubble benefits as I see them:
1: experience in large space based optics and space-based repair missions. While the repairs with the shuttle have ended up being more expensive than a new telescope, the knowledge we've gained fixing the Hubble will pay off in the future where at least some level of space based repair capability will be needed.
2: We now have a far better grasp of the overall structure and composition of the universe than before. Remember that big hullabaloo about the universe's expansion speeding up and dark matter and dark energy. Well, you can thank Hubble for being one of the major instruments responsible for those obervations. We are now much closer to understanding the formation and structure of the universe than ever before. For quite a while, it looked like there were fundamental questions we'd never be able to answer. Now, we've got high accuracy measurements of the curvature, matter/dark matter/dark energy composition of the universe. This is one of the most exciting periods in astrophysics in decades. The tangible beneftis of this evidence are as follows:
2a: These detailed comological observations can be used to test physics theories. Thing like superstring theory and quantum gravity and other theories that can't be tested in the lab can be tested using the history of the universe as a gigantic physics experiment. About a hundred years ago, some wierd observation about the photoelectric effect led to the development of quantum physics and then semiconductors, lasers, modern chemistry, molecular biology, modern materials science, etc. If we can use this new data to help replace the standard model of physics, we might suddenly find a host of new technologies. A true understanding of quantum gravity might lead to no practical applications or it might lead to the ability to manipulate gravity and space-time in a controllable manner. I leave it as an exercise for the reader to imagine what the latter would mean for engineering.
2b: we are closer to being able to understand the how and why of the formation of the universe. As an atheist, scientific understanding of the universe is something akin to being able to read the Bible for the first time. Even for the non-atheistic, I think that having an obervational understanding of where we come from and why we're here is very important and a worthwhile pursuit.
Although your plan is a cool one, it lacks a certain practicality. Namely, how do we plan to pay for all of these telescopes? NASA doesn't even havea single Hubble equivalent repalcement on the *drawing board* yet. They seem to be dead set against doing a repair on an existing telescope, much less put up a constellation of new ones.
USing mass production for telescoeps isn'tterribly effective either as the launch costs are still a major component of the cost equation. IIRC, a Titan IV launch is about $400 million. I can assure you that universities won't be able to afford a half billion dollar instrument.
Newer designs like the Webb do bring costs down and it might be possible to geta fleet of Webb-like optical scopes up at some point but that's probably a 2015-2020 timeframe. In the meantime, we really have to keep the Hubble going until the WEbb provides at least a partial replacement capacity. (something that most posters seem to forget is that the cancelled SM4 repair was to extend the life of Hubble until 2010 when the Webb will be operational. Without the repair, Hubble could be dead in less than a year.)
Ummm, no offense but do you know ANYTHING about astronomy? The Hubble gives high quality data about the luminosity, composition and redshift for stellar objects. It's not a guess - we can get detailed information about the elemental makeup of stars and galaxies out to nearly the end of the universe with spectroscopy. The Hubble deep field measurements along with Hubble supernova obervations have been a critical component along with the wide angle microwave anisotropy data that has allowed us to completely revolutionize astrophysics in the last few years.
Because of this, we now have solid numbers confirmed through independent observation techniques about the age, expansion rate and general composition of the universe. A decade ago, the error bars on some of those variables had error bars nearly as big as the values! Measurements like these also might help to verify or debunk things like superstring theory which we have little hope of doing with terrestrial experiments.
The space infrastructure you speak of is at least several decades off. You talk about space elevators as if they're something that's going to happen soon. We still don't even know if it will be practical to build one of these things. When someon is capable of making even a foot of nanotube rope with a tensile strength that's within an order of magnitude of what's eventually needed, I'll start to take space elevators a little more seriously.
What you're talking about is equivalent to telling me I should stop changing the oil in my car and start walking everywhere for some indeterminant length of time so that you can build a car factory in my backyard. I'm sorry but that's silly.
The cost of fixing the Hubble is less than 2% of the cost of the ISS which contributes virtually nothing meaningful in terms of science and also very little in terms of furthering the space infrastructure you talk about. If you want to get your space infrastructure started, can the ISS and use that money.
The Hubble has been one of the most spectacularly successful space science missions in history. I've heard quoted that it has been responsible for about 1/3rd of the science papers coming out of NASA over the last decade! It is NOT a useless little space telescope as you say. Furthermore, the SM4 upgrade that the repair mission will provide will give a huge boost on the scope capabilities. The optics in Hubble are still excellent. The new IR camera that would have been installed would have given a 10-fold increase in Hubble's IR capabilities and the new wide field camera would have let us push the deep field exposures much further out to the edge of the observable universe. The UDF got us 90% of the way back to the dark era where light cuts off. I don't know the exact level of improvement in dark noise with the SM4 cameras vs the previous servicing mission but it probably would have been enough to push us back to limit of space based astronomy - without needing some gradiose fleet of giant telescopes.
We lived in the ignorance of the danger of large extraplanetary impactors until very recently and it hasn't done us in yet. A base on Mars won't be a viable escape plan for at least a century until the Mars base becomes truly self-sufficient. Until then, we're much better off doing cataloging of asteroids and getting a better understanding of the solar system around us - which is information derived from the very sort of science you want to cut with the Mars mission.
Don't get me wrong, I'm all for a manned Mars mission but not at the cost of gutting a very successful robotic space program which already uses far less money than our rather poor manned space program. If you want to find a place to cut budgets, kill the ISS - it isn'ta valid starting point for going to Mars because of the orbital inclination and is basically useless from a scientific perspective.
Something like %35 of the NASA scientific papers in the last decade have come from Hubble and the repair mission would cost 2% of the estimated cost to finish the ISS. It's just perverse to kill Hubble and then continue to work on the ISS which is a much bigger money hog. If we want to send people to Mars, we need to be decisive and just do it. The only way NASA can be decisive about it is to free up the majority of its budget. The only way it can do that is to remove the Shuttle and ISS funding and direct it towards the focussed devlopment of technology directly related to getting to Mars and the Moon.
Furthermore, if you want to inspire the public, look at the unmanned space missions. A far larger proportion of the public is familiar with the Hubble and the Mars rovers than with the ISS. The former have returned enourmous amounts of valuable scientific information and been the most popular attractions at the NASA website. It sys something that the heavist traffic in the history of NASA came from a pair of robotic rovers.
I'm fairly certain that image is from the microscopic imager which means that it's not a tire track. The folks at enterprise mission are grade A kooks but that is an interesting photo. I'd be curious to see if the size of this particular 'fossil' is similar to the rottini artifact. They look strikingly similar and this was taken pre-RAT-drilling which means that it can't be an artifact of the drilling process.
If I was something like those artifacts on Earth, the first thing I'd think of was that I'd just found a fossil and I know that a lot of people at NASA are thinking the same. I wonder if there's any criterion that could be used to prove or disprove the authenticity of these fossils with therover instruments?
I was looking at the big version and thought you were smokin' crack or something. However, a quick at the smaller picture and I'm seeing the same pattern. It's almost certainly our brains picking out a meaningless correlation.
It's not a gravitational lens as the other response suggests. Gravitational lensing also severly distorts the image and anything powerful enough to create a distortion as big as those rings would make the whole image look like it was viewed through a fisheye lens. Plus I can't see any mirroring across the center - a gravitational lens should show duplicated images on etiher side of the center like a kaleidoscope.
Actually, it looks more like a big spiral to me now that I look at it more closely.
It's probably just like the human-like figure they found when they first strated going galactic surveys.
Either that or the cosmos is trying to hypnotize astronomers to to do wacky hijinks 'ala Scooby Doo.
(And I would have gotten away with it too if it hadn't been for those nosy Slashdotters!)
The VLA and VLBA are, as you said, radio telescopes. First, they give VERY different information than what Hubble gives which means they can't supplant Hubble. Furthermore, optical baseline interferometry requires a stability on the same order as the wavelength of the radiation being measured. With the VLBA and measuring 1M radio waves, this is easy. As long as your radio telescoeps aren't jumping around a significant fraction ofa meter with respect to each other (in which case, you've probably got bigger problems to worry about), it works great. Doing the same with optical scopes requires that they be stable to each other to a small fraction of a micron. This is possible when the scoeps are right nect to each other and can share a very similar optical path therough the atmosphere and have adaptive optics. To do this on Earth on opposite side of the world would be a waste of time. There are plans to try long baseline optical interferometry - and guess what - they're all space based. No atmosphere, no ground vibrations, etc.
You can get additional sensitivity by grouping lots of ground scopes but resolution comes from being able to do interferometry or adaptive optics. The current and forseen ground based technologies for both of these surpass Hubble in many areas but don't replace it.
While I'm not a terribly big O'Keefe fan, I think that this doesn't give the man enough credit. He may not be a space scientist but he has shown a good head for managing NASA financially in his tenure. I suspect that Hubble is getting canned because he's being pressured from above. The Moon/Mars initiative basically guts NASA's budget for the next 20 years. While I'm very stongly in favor of sending up SM4, given the choice between repairing Hubble or having to can the Webb telescope, I'd lose Hubble. I think we whould have both telescopes and lose one of the tin cans off the ISS but they didn't consult me.
O'Keefe really shouldn't be the brunt of anger here - he's just doing his job and probably doesn't feel too good about it. Put the blame on the administration's space initiative program. While I support certain features like the scrapping of the next-gen shuttle and the eventual scuppering of ISS, the eventual gutting of the unmanned science programs for a poorly thought out manned presence on the moon is just plain stupid.
Thanks for the good comments, all these unimformed 'D00d, Hubble bites ass, ground based scopes and new telescopes will totally roxxor it!' comments are starting to chafe me...
Just a few comments: 1: Ample evidence shows that at least part of NASA has internally concluded that SM4 is safer than going to the ISS. That doesn't even take into account the fact that SM4 requires 2 flights and the ISS requires 25+. While the public spin is that this is for safety, I strongly suspect that is simply a boogeyman to try and avoid external questioning of the decision. While I can sympathize with NASA's budget problems and a need to kill projects to be able to meet the requirements of this new Moon/Mars initiative, I don't appreciate getting a whitewash about the reasons. While it can be argued that SM4 is only a few percent of the ISS budget and therefore not a productive place for NASA to cut fat, the projected Bush plan will hit NASA hard, requiring them to cut budgets wherever they can.
2: I was under the impression that SM4 was going to replace the gyros. I could have sworn they were replaced once before - or was this the reaction wheels?
3&4: Agreed - while there's been some work on using lasers to excite upper atmospheric gasses to make artificial guide stars so that you can look away from the bright stars, this tech isn't yet at a useful stage, to my knowledge.
and 5: The Webb telescope is a vast improvement over Hubble in terms of resolution and sensitivity. However, it fails to cover the shorter visible spectrum and UV. Since UV can't be done from the ground, this puts a major hole in our space based telescope capabilities - there are lots of astronomical observations that require UV.
Futhermore, there's a gap of something like 3 years between the presently planned death of Hubble and the Webb going up. Even worse, the Webb uses a folding mirror that hasn't been operationally tested, a launcher that has a history of catastrophic failure and a location that's way beyond our ability to go to for servicing. If the Webb suffers some sort of failure, we face the very real possibility of losing our space-based optical imaging capabilities for 5-10 years. At a time when we're on the verge of cracking some of the long-standing questions about the origins and fundamental constants of the universe this is an unacceptable situation. At the least, we should look at a way to extend Hubble's lifetime until we have Webb up and operating reliably.
I was thinking of someone faking the documents (perhaps even a disgruntled NASA employee) and sending them to the Zubrin crowd. However, since NASA's keeping quiet about this, I'm assuming they're legit.
The possibility of a hoax occurred to me as well. However, if it is a hoax, it's a good one - the general tone and feel looks like a NASA document. Furthermore, to my knowledge, NASA has not disavowed these documents. Given their high visibility, NASA would have said something if they were faked.
Listen, dipshit, this is analysis carried out by NASA. Someone at NASA anonomously leaked the analysis documents to the public which directly contradicts NASA's public stance. How about RTFA before calling FUD. Both documents can be accessed from the Mars society website and probably other places as well. Try actually reading those documents - oh wait, that would get in the way of speading your own FUD, nevermind.
The 'lifeboat' capability of ISS is basically illusory. The ISS cannot handle the additional life support load of a shuttle-load of astronauts on top of its exiting crew. Even if the shuttle can succesfully dock at ISS after being damaged, you do not have a meaningful extension of the amount of time to repair the shuttle/launch a rescue mission. If you read below, a Hubble mission has the option of having another shuttle ready to go up for a rescue mission in a few days. This is not possible with the ISS. It is possible that the Russians could start doing a Soyuz lifeboat brigade but each Soyuz can carry 3 people, IIRC. Assume an ISS crew of 3 and then a shuttle crew of 6. Thats two seperate soyuz launches and using the lifeboat Soyuz to get everyone off. NASA is already very concerned about the life support systems on the ISS. The implicit conclusion of the leaked reports is that there is a significant probability of life support failure with that many people on board. Can the Russians get two seperate launches up to ISS fast enough to deal with a life support failure? Possible but by no means guaranteed.
If you opt to repair the damage, the Hubble and ISS missions will have the same capabilites - the Hubble servicing mission isn't planned until after the damage inspection and repair fixes are planned to be implemented anyways. The planned repair capability is planned to be on the shuttle, not the ISS which means that the ISS gives no advantages in being able to do repairs. It is noteworthy that the Columbia was lost due to massive amounts of damage to the wing. The shuttles have flown with large amounts of damage to the thermal control system before and been fine. (over 3000 instances of tile damage >1 inches in diameter have been recorded) The shuttle even returned several times with missing tiles and once with a damaged area 10x20 inches in size. Barring massive damage like on Columbia, in flight repairs are quite realistic.
If you have to go in and do a rescue mission, the Hubble repair mission actually has a huge advantage. The Hubble repair mission can be launched right before an ISS mission - allowing a second shuttle to be prepped and ready to launch. That second shuttle can be quickly retasked to do a rescue if the Hubble mission has problems. You can't do that with an ISS mission since it would require having the next ISS mission ready to go before launching - then the third mission would have to be prepped before the second flight could depart - and so on. With only 3 active shuttles, this is basically impossible. Therefore, ISS missions don't have a rescue option.
Even worse, although the total space debris impact probability is about the same in both orbits, going to the ISS greatly reduces the ability of the Shuttle to maneuver to avoid incoming debris. Therefore, the danger of debilitating debris damage going to the ISS is higher than going to the Hubble. This notably includes a significantly higher danger of imacts that would depressurize the crew cabin. The estimated probability of 'critical' impact damage during the completion of ISS is worse than 1 in 12. As for adding the Hubble repair mission - quote, "It is noteworthy to observe that the collective odds of thermal control system critical damage for the remaining 25 flights to complete the assembly of the ISS are not significantly increased with the addition of one HST Servicing Mission from the current value of 1 in 11.6."
All of the above is taken *directly* from NASA's own analysis of the situation. If Hubble did actually pose a significant risk to astrona
The Mars Society has got copies of the leaked documents on its page. I don't know if those documents were sent to Mars Society of if they're mirror from another site.
OK, I swear, this is the last time I'll post this message in this thead....
The James Webb telescope is cool, yes. But it can't see anything below 600nm in wavelength. In these IR wavelengths, the Webb pwn3z!!!11!! Hubble but only at those wavelenghts. If you wan't to view something green or in the UV, you're out of luck with Webb. Although I believe that one of the other current telescopes can see some UV, we've got a huge gap in out observing capabilities with no Hubble.
Furthermore, There's no guarantee that the Webb will work. It's going up on an Arianne 5 which blows up with distressing regularity. The Webb uses an untested folding mirror - what if it pulls a Gallileo and the mirror doesn't deploy? It's not like we can go and fix it at L2 or anything.
Furthermore, the optics in Hubble are still just fine. It's got problems with failing gyroscopes which would have been replaced with the cancelled repair. Furthermore, the new cameras (which are already completed and cost us $400 million, BTW) upgrade Hubble to the point where it's as good as any of the new telescopes we've lofted, short of a larger aperture size.
It's not like we throw out the Keck because a new CCD camera comes our - we use the same optics and throw in a new camera assembly. The cancelled Hubble mission is just like that - the Hubble optics are still just fine. There's no reason that we can't take that 18 years and extend it another 8-10 with the servicing mission.
OK, I've posted this same message, like 10 times, already in this discussion and I'm starting to feel like a Spam-bot or something. I want to make sure people read this, though.
Leaked NASA documents (you can see them at the Mars Society web page) show that Hubble is no more dangerous than going to ISS. In fact, the high orbital inclination of ISS probably makes it more dangerous to get to. If this were actually an issue of astronaut safety, I'd be applauding NASA for making the right decision. However, this is clearly a politically motivated move to save money for the ISS.
No argument about Webb being tecnically superior to Hubble. However, there's two problems.
1: as the other reply mentions, Webb can't do green to UV measurements. Ground based telescopes lack the ability to do good UV measurements due to atmospheric absorbtion. There's still plenty of stuff that astronomers want to do in those wavelenghts.
2: The Webb isn't up and running. What if that Ariane 5 blows up like they seem to be prone to do? What if the mirror doesn't deploy properly? The folding mirror has never been operationally tested - we never did conclusively figure out why Gallileo's main antenna didn't deploy - what if Webb does the same? What if the cryogenic dewar springs a leak or outgasses faster than anticipated? What if any number of a million possible things go wrong and the Webb doesn't work We can't fix it at L2 so we're now stuck with a dead telescope. We should at least keep Hubble running until Webb is properly running.
As I and some others have pointed out, the ISS is actually riskier to get to because of it's high orbital inclination. As it is, Hubble needs a single servicing mission at a 2% risk which is the same now as it was before either Columbia or Challenger. Docuents leaked from NASA confirm this. I have no problem letting Hubble die if it actually does pose a threat to astronauts but this is a purely politically motivated move.
Slashdot Mirror
I agree that in hindsight, we would have been better off just lunching 'disposable' telescopes and not spending the money on repairing Hubble. However, with no projected replacement for Hubble anythime in the next 10+ years (the Webb IR telescope only replaces part of the Hubble's functionality), we should commit to one last servicing mission. If for no other reason, we have to send something up to deorbit Hubble in a controlled manner. Once the gyros go out and Hubble starts tumbling, we're screwed - we can't repair it or control its deorbit at that point. It's big enough to cause damage on the ground and it passes over highly populated areas.
Plus, Adaptive ground optics cannot replace Hubbble - they can only view the sky in a very narrow field of view near a bright guidea star to properly controll the optics. Also, you can't do IR or US spectroscopy with ground based instruments, no matter how advanced they get because of atmospheric absorbtion.
I agree that we shouldn't keep dupming money into Hubble forever but the SM4 repair mission is cheap in comparison to the ISS (2% of the ISS shuttle budget alone) and will prevent a huge loss of space-based telescope capabilites. We've ready already sunk a ton of money into Hubble, this one last bit will give us a much improved instrument that will last at least an additional 6 years. Personally, the cost-to benefit is too good to not repair Hubble. Once the Webb goes up, we can lose Hubble without it being TOO painful to the astronomy community but that won't happen until 2012 at the earliest.
Congratulations, you just once again demonstrated that you don't know what you're talking about.
The original wavelengths ARE known. Every piece of observation evidence ever collected supports the idea that the laws of physics that regulate spectral emission have not changed at any point in the visible history of the universe. Those spectral lines are very well known and very accurate. By looking how a particular hydrogen line has redshifted, you immediately know what the redshift is to a great deal of accuracy. The uncertainty has been determining the distance to an object. Unless you have something like a class 1a supernova to use as an absolute distance gauge, you know the object's speed but not distance. The determination of an accurate Hubble constant require both values.
Again, the dark era is pretty damned certain. We know that the universe is expanding away from us. This implies that the visible matter of the universe was once much more compact and dense. Therefore, it simply a matter of back extrapolation to calculate the density of the matter at a given point in time. The dark era is simply when the density of matter would have caused enough light-matter interaction to ionize bulk interstellar gas, making it impermeable to light. There is nothing controversial or speculative about this - the microwave background radiation we can observe is a direct image of this plasma. Optical observations haven't been able to see back to that point yet but we're getting close.
I guess that if you posit that the Big Bang didn't happen and that the universe isn't expanding that it is possible the dark era didn't happen but otherwise, it is a forgone conclusion. There are still some theories like 'lazy light' and alternate gravitational behaviour that are competitors to the Big Bang but they are matching actual data even more poorly as time goes along. Mostly, astrophysicists argue over details on the Big Bang theory these days. Very little serious effort is given to alternate theories since the Big Bang theory fits the data so much better than everything else.
Also, you've completely missed my point. We aren't sitting around and looking at pretty pictures - this is serious science, some of which - like studying interstellar plasma behavior may have practical benefits to building the very space infrastructure you talk about. Cancelling the Hubble will have almost no positive effect upon building a space infrastructure but it WILL have a major negative effect on scientific studies.
I wholeheartedly support robotic and manned missions to Mars and other planets to get hands on sample to work with. However, we have learned FAR more about the solar system and the universe and physics from remote observational tools like Hubble than all the the planetary landers and moon landings put together. Hell, most of the data we have on Mars comes from remote imaging just like what Hubble does.
Further, insisting upon some nebulous, huge space infrastructure is necessary to get to Mars is false. The Mars Direct plan by Zubrin, while having some flaws, demonstrates that you need little to no infrastructure to get to Mars. Big lunar mines make no sense in terms of orbital energetics. It's as if the settlers of the old West had waited for the US government to build a freeway system to be built before heading out. IF that had been the case, the US would still be stranded at the Mississippi river and the native Americans would probably have been much better happier.
If we want to go to Mars, we should go to Mars. If we want to build space telescopes, we should build htem on the ground and launch them. If we just go to Mars and start making colonies, we will eventually build the space infrastructure you talk about as it becomes necessary. There is no way that taxpayers will invest in the infrastructure first and then go - the Shuttle is a prime example of what happens when you start working that way.
WHOA... [rubs eyes] ...
WHOA... an intelligent comment? Are you sure you're posting on the right website?
BTW, good suggestion, I just fired off two E-mails to my senators.
To follow up on the other response:
Even worse, without the Hubble SM4 repair missions, the Hubble could be non-operation as soon as this year. They're hoping to stretch it out to 2007 but that still leaves a *5* year gap with no wide field UV/optical/IR telescope. The SM4 mission is supposed to get the Hubble running out to 2010 which would allow it to overlap the Webb telescope if we're careful. The Webb isn't a good Hubble replacement but better than nothing. As far as replacing the UV/visible cabailities of the Hubble, a replacement telescope isn't even on the *drawing board* yet.
To make things even better, when the Hubble loses control, it will start tunbmling and basically make repairs impossible. Furthermore, at that point, we won't be able to control the Hubble deorbit. The Hubble is big enough to have large pieces of debris hit the ground and the orbital plane goes over some densely populated areas. So, unless we want to play 'Pin the Hubble on the City', we've got to send SOMETHING up to bring it out of orbit in a controlled manner.
Helpful hint: before making authoritative posts about scientific matters please ensure that you have half a clue about said scientific subject first.
Fission and fusion are perfectly well understood. The fundamentals involved were well hammered out by the late 40's. The experimental observation of the particles involved was done by the late 60's and if you want to be stickler and insist on getting wierd, exotic particles like the W, then we've had fission and fusion completely nailed down for 20 years now.
The reason that we don't have controllable fusion power has nothing to do with understanding the fusion process. Plasma instabilities caused by the interaction of the plasma's own magnetic fields with the containment field cause the reaction to be unstable and die out. Ironically, observations of space-based plasmas done with instruments like the Hubble have proved and are proving quite useful in getting these plasma instabilities under control.
As far as practicality, there are presently NO practical applications for the stuff that particle accelerators have done in the last 40 years or so. It is pure and basic research at its best. Of course, there's the hope that this research will lead to a better unified field theory which could have substantial spin-off applications but so far, this has not been the case. Virtually all of the modern technology we use came from high energy physics research done before 1950. Most of it came from research done before 1930 - the research up to that point was enough to invent quantum physics as most engineers know it.
And finally, your comment about fuzzy blobs in the sky is so monumentally asinine and moronic, I'm not certain how to even respond. The observation and formation and testing of hypotheses is EXACTLY WHAT SCIENCE *IS*!
While the parent was kinda... well, lame, at least the poster was cool about it. It's a seriously posed question and doesn't deserve to be modded as a troll.
To answer the question, here are the tangible Hubble benefits as I see them:
1: experience in large space based optics and space-based repair missions. While the repairs with the shuttle have ended up being more expensive than a new telescope, the knowledge we've gained fixing the Hubble will pay off in the future where at least some level of space based repair capability will be needed.
2: We now have a far better grasp of the overall structure and composition of the universe than before. Remember that big hullabaloo about the universe's expansion speeding up and dark matter and dark energy. Well, you can thank Hubble for being one of the major instruments responsible for those obervations. We are now much closer to understanding the formation and structure of the universe than ever before. For quite a while, it looked like there were fundamental questions we'd never be able to answer. Now, we've got high accuracy measurements of the curvature, matter/dark matter/dark energy composition of the universe. This is one of the most exciting periods in astrophysics in decades. The tangible beneftis of this evidence are as follows:
2a: These detailed comological observations can be used to test physics theories. Thing like superstring theory and quantum gravity and other theories that can't be tested in the lab can be tested using the history of the universe as a gigantic physics experiment. About a hundred years ago, some wierd observation about the photoelectric effect led to the development of quantum physics and then semiconductors, lasers, modern chemistry, molecular biology, modern materials science, etc. If we can use this new data to help replace the standard model of physics, we might suddenly find a host of new technologies. A true understanding of quantum gravity might lead to no practical applications or it might lead to the ability to manipulate gravity and space-time in a controllable manner. I leave it as an exercise for the reader to imagine what the latter would mean for engineering.
2b: we are closer to being able to understand the how and why of the formation of the universe. As an atheist, scientific understanding of the universe is something akin to being able to read the Bible for the first time. Even for the non-atheistic, I think that having an obervational understanding of where we come from and why we're here is very important and a worthwhile pursuit.
Although your plan is a cool one, it lacks a certain practicality. Namely, how do we plan to pay for all of these telescopes? NASA doesn't even havea single Hubble equivalent repalcement on the *drawing board* yet. They seem to be dead set against doing a repair on an existing telescope, much less put up a constellation of new ones.
USing mass production for telescoeps isn'tterribly effective either as the launch costs are still a major component of the cost equation. IIRC, a Titan IV launch is about $400 million. I can assure you that universities won't be able to afford a half billion dollar instrument.
Newer designs like the Webb do bring costs down and it might be possible to geta fleet of Webb-like optical scopes up at some point but that's probably a 2015-2020 timeframe. In the meantime, we really have to keep the Hubble going until the WEbb provides at least a partial replacement capacity. (something that most posters seem to forget is that the cancelled SM4 repair was to extend the life of Hubble until 2010 when the Webb will be operational. Without the repair, Hubble could be dead in less than a year.)
Ummm, no offense but do you know ANYTHING about astronomy? The Hubble gives high quality data about the luminosity, composition and redshift for stellar objects. It's not a guess - we can get detailed information about the elemental makeup of stars and galaxies out to nearly the end of the universe with spectroscopy. The Hubble deep field measurements along with Hubble supernova obervations have been a critical component along with the wide angle microwave anisotropy data that has allowed us to completely revolutionize astrophysics in the last few years.
Because of this, we now have solid numbers confirmed through independent observation techniques about the age, expansion rate and general composition of the universe. A decade ago, the error bars on some of those variables had error bars nearly as big as the values! Measurements like these also might help to verify or debunk things like superstring theory which we have little hope of doing with terrestrial experiments.
The space infrastructure you speak of is at least several decades off. You talk about space elevators as if they're something that's going to happen soon. We still don't even know if it will be practical to build one of these things. When someon is capable of making even a foot of nanotube rope with a tensile strength that's within an order of magnitude of what's eventually needed, I'll start to take space elevators a little more seriously.
What you're talking about is equivalent to telling me I should stop changing the oil in my car and start walking everywhere for some indeterminant length of time so that you can build a car factory in my backyard. I'm sorry but that's silly.
The cost of fixing the Hubble is less than 2% of the cost of the ISS which contributes virtually nothing meaningful in terms of science and also very little in terms of furthering the space infrastructure you talk about. If you want to get your space infrastructure started, can the ISS and use that money.
The Hubble has been one of the most spectacularly successful space science missions in history. I've heard quoted that it has been responsible for about 1/3rd of the science papers coming out of NASA over the last decade! It is NOT a useless little space telescope as you say. Furthermore, the SM4 upgrade that the repair mission will provide will give a huge boost on the scope capabilities. The optics in Hubble are still excellent. The new IR camera that would have been installed would have given a 10-fold increase in Hubble's IR capabilities and the new wide field camera would have let us push the deep field exposures much further out to the edge of the observable universe. The UDF got us 90% of the way back to the dark era where light cuts off. I don't know the exact level of improvement in dark noise with the SM4 cameras vs the previous servicing mission but it probably would have been enough to push us back to limit of space based astronomy - without needing some gradiose fleet of giant telescopes.
We lived in the ignorance of the danger of large extraplanetary impactors until very recently and it hasn't done us in yet. A base on Mars won't be a viable escape plan for at least a century until the Mars base becomes truly self-sufficient. Until then, we're much better off doing cataloging of asteroids and getting a better understanding of the solar system around us - which is information derived from the very sort of science you want to cut with the Mars mission.
Don't get me wrong, I'm all for a manned Mars mission but not at the cost of gutting a very successful robotic space program which already uses far less money than our rather poor manned space program. If you want to find a place to cut budgets, kill the ISS - it isn'ta valid starting point for going to Mars because of the orbital inclination and is basically useless from a scientific perspective.
Something like %35 of the NASA scientific papers in the last decade have come from Hubble and the repair mission would cost 2% of the estimated cost to finish the ISS. It's just perverse to kill Hubble and then continue to work on the ISS which is a much bigger money hog. If we want to send people to Mars, we need to be decisive and just do it. The only way NASA can be decisive about it is to free up the majority of its budget. The only way it can do that is to remove the Shuttle and ISS funding and direct it towards the focussed devlopment of technology directly related to getting to Mars and the Moon.
Furthermore, if you want to inspire the public, look at the unmanned space missions. A far larger proportion of the public is familiar with the Hubble and the Mars rovers than with the ISS. The former have returned enourmous amounts of valuable scientific information and been the most popular attractions at the NASA website. It sys something that the heavist traffic in the history of NASA came from a pair of robotic rovers.
I'm fairly certain that image is from the microscopic imager which means that it's not a tire track. The folks at enterprise mission are grade A kooks but that is an interesting photo. I'd be curious to see if the size of this particular 'fossil' is similar to the rottini artifact. They look strikingly similar and this was taken pre-RAT-drilling which means that it can't be an artifact of the drilling process.
If I was something like those artifacts on Earth, the first thing I'd think of was that I'd just found a fossil and I know that a lot of people at NASA are thinking the same. I wonder if there's any criterion that could be used to prove or disprove the authenticity of these fossils with therover instruments?
I was looking at the big version and thought you were smokin' crack or something. However, a quick at the smaller picture and I'm seeing the same pattern. It's almost certainly our brains picking out a meaningless correlation.
It's not a gravitational lens as the other response suggests. Gravitational lensing also severly distorts the image and anything powerful enough to create a distortion as big as those rings would make the whole image look like it was viewed through a fisheye lens. Plus I can't see any mirroring across the center - a gravitational lens should show duplicated images on etiher side of the center like a kaleidoscope.
Actually, it looks more like a big spiral to me now that I look at it more closely.
It's probably just like the human-like figure they found when they first strated going galactic surveys.
Either that or the cosmos is trying to hypnotize astronomers to to do wacky hijinks 'ala Scooby Doo.
(And I would have gotten away with it too if it hadn't been for those nosy Slashdotters!)
The VLA and VLBA are, as you said, radio telescopes. First, they give VERY different information than what Hubble gives which means they can't supplant Hubble. Furthermore, optical baseline interferometry requires a stability on the same order as the wavelength of the radiation being measured. With the VLBA and measuring 1M radio waves, this is easy. As long as your radio telescoeps aren't jumping around a significant fraction ofa meter with respect to each other (in which case, you've probably got bigger problems to worry about), it works great. Doing the same with optical scopes requires that they be stable to each other to a small fraction of a micron. This is possible when the scoeps are right nect to each other and can share a very similar optical path therough the atmosphere and have adaptive optics. To do this on Earth on opposite side of the world would be a waste of time. There are plans to try long baseline optical interferometry - and guess what - they're all space based. No atmosphere, no ground vibrations, etc.
You can get additional sensitivity by grouping lots of ground scopes but resolution comes from being able to do interferometry or adaptive optics. The current and forseen ground based technologies for both of these surpass Hubble in many areas but don't replace it.
While I'm not a terribly big O'Keefe fan, I think that this doesn't give the man enough credit. He may not be a space scientist but he has shown a good head for managing NASA financially in his tenure. I suspect that Hubble is getting canned because he's being pressured from above. The Moon/Mars initiative basically guts NASA's budget for the next 20 years. While I'm very stongly in favor of sending up SM4, given the choice between repairing Hubble or having to can the Webb telescope, I'd lose Hubble. I think we whould have both telescopes and lose one of the tin cans off the ISS but they didn't consult me.
O'Keefe really shouldn't be the brunt of anger here - he's just doing his job and probably doesn't feel too good about it. Put the blame on the administration's space initiative program. While I support certain features like the scrapping of the next-gen shuttle and the eventual scuppering of ISS, the eventual gutting of the unmanned science programs for a poorly thought out manned presence on the moon is just plain stupid.
Thanks for the good comments, all these unimformed 'D00d, Hubble bites ass, ground based scopes and new telescopes will totally roxxor it!' comments are starting to chafe me...
Just a few comments:
1: Ample evidence shows that at least part of NASA has internally concluded that SM4 is safer than going to the ISS. That doesn't even take into account the fact that SM4 requires 2 flights and the ISS requires 25+. While the public spin is that this is for safety, I strongly suspect that is simply a boogeyman to try and avoid external questioning of the decision. While I can sympathize with NASA's budget problems and a need to kill projects to be able to meet the requirements of this new Moon/Mars initiative, I don't appreciate getting a whitewash about the reasons. While it can be argued that SM4 is only a few percent of the ISS budget and therefore not a productive place for NASA to cut fat, the projected Bush plan will hit NASA hard, requiring them to cut budgets wherever they can.
2: I was under the impression that SM4 was going to replace the gyros. I could have sworn they were replaced once before - or was this the reaction wheels?
3&4: Agreed - while there's been some work on using lasers to excite upper atmospheric gasses to make artificial guide stars so that you can look away from the bright stars, this tech isn't yet at a useful stage, to my knowledge.
and 5: The Webb telescope is a vast improvement over Hubble in terms of resolution and sensitivity. However, it fails to cover the shorter visible spectrum and UV. Since UV can't be done from the ground, this puts a major hole in our space based telescope capabilities - there are lots of astronomical observations that require UV.
Futhermore, there's a gap of something like 3 years between the presently planned death of Hubble and the Webb going up. Even worse, the Webb uses a folding mirror that hasn't been operationally tested, a launcher that has a history of catastrophic failure and a location that's way beyond our ability to go to for servicing. If the Webb suffers some sort of failure, we face the very real possibility of losing our space-based optical imaging capabilities for 5-10 years. At a time when we're on the verge of cracking some of the long-standing questions about the origins and fundamental constants of the universe this is an unacceptable situation. At the least, we should look at a way to extend Hubble's lifetime until we have Webb up and operating reliably.
I was thinking of someone faking the documents (perhaps even a disgruntled NASA employee) and sending them to the Zubrin crowd. However, since NASA's keeping quiet about this, I'm assuming they're legit.
Dammit, Slashdot stripped my foghorn Leghorn modifiers out of my message....
I got modded INSIGHTFUL for that? It's a joke, son! Slashdot...sheesh...
The possibility of a hoax occurred to me as well. However, if it is a hoax, it's a good one - the general tone and feel looks like a NASA document. Furthermore, to my knowledge, NASA has not disavowed these documents. Given their high visibility, NASA would have said something if they were faked.
Listen, dipshit, this is analysis carried out by NASA. Someone at NASA anonomously leaked the analysis documents to the public which directly contradicts NASA's public stance. How about RTFA before calling FUD. Both documents can be accessed from the Mars society website and probably other places as well. Try actually reading those documents - oh wait, that would get in the way of speading your own FUD, nevermind.
The 'lifeboat' capability of ISS is basically illusory. The ISS cannot handle the additional life support load of a shuttle-load of astronauts on top of its exiting crew. Even if the shuttle can succesfully dock at ISS after being damaged, you do not have a meaningful extension of the amount of time to repair the shuttle/launch a rescue mission. If you read below, a Hubble mission has the option of having another shuttle ready to go up for a rescue mission in a few days. This is not possible with the ISS. It is possible that the Russians could start doing a Soyuz lifeboat brigade but each Soyuz can carry 3 people, IIRC. Assume an ISS crew of 3 and then a shuttle crew of 6. Thats two seperate soyuz launches and using the lifeboat Soyuz to get everyone off. NASA is already very concerned about the life support systems on the ISS. The implicit conclusion of the leaked reports is that there is a significant probability of life support failure with that many people on board. Can the Russians get two seperate launches up to ISS fast enough to deal with a life support failure? Possible but by no means guaranteed.
If you opt to repair the damage, the Hubble and ISS missions will have the same capabilites - the Hubble servicing mission isn't planned until after the damage inspection and repair fixes are planned to be implemented anyways. The planned repair capability is planned to be on the shuttle, not the ISS which means that the ISS gives no advantages in being able to do repairs. It is noteworthy that the Columbia was lost due to massive amounts of damage to the wing. The shuttles have flown with large amounts of damage to the thermal control system before and been fine. (over 3000 instances of tile damage >1 inches in diameter have been recorded) The shuttle even returned several times with missing tiles and once with a damaged area 10x20 inches in size. Barring massive damage like on Columbia, in flight repairs are quite realistic.
If you have to go in and do a rescue mission, the Hubble repair mission actually has a huge advantage. The Hubble repair mission can be launched right before an ISS mission - allowing a second shuttle to be prepped and ready to launch. That second shuttle can be quickly retasked to do a rescue if the Hubble mission has problems. You can't do that with an ISS mission since it would require having the next ISS mission ready to go before launching - then the third mission would have to be prepped before the second flight could depart - and so on. With only 3 active shuttles, this is basically impossible. Therefore, ISS missions don't have a rescue option.
Even worse, although the total space debris impact probability is about the same in both orbits, going to the ISS greatly reduces the ability of the Shuttle to maneuver to avoid incoming debris. Therefore, the danger of debilitating debris damage going to the ISS is higher than going to the Hubble. This notably includes a significantly higher danger of imacts that would depressurize the crew cabin. The estimated probability of 'critical' impact damage during the completion of ISS is worse than 1 in 12. As for adding the Hubble repair mission - quote, "It is noteworthy to observe that the
collective odds of thermal control system critical damage for the remaining 25 flights
to complete the assembly of the ISS are not significantly increased with the addition of
one HST Servicing Mission from the current value of 1 in 11.6."
All of the above is taken *directly* from NASA's own analysis of the situation. If Hubble did actually pose a significant risk to astrona
The Mars Society has got copies of the leaked documents on its page. I don't know if those documents were sent to Mars Society of if they're mirror from another site.
www.marssociety.org
It should be fairly clsoe to the top, still.
Dude, all he has to do is have the Death Star make a hyperspace jump and we're toast. Keep it down, he might hear you!
OK, I swear, this is the last time I'll post this message in this thead....
The James Webb telescope is cool, yes. But it can't see anything below 600nm in wavelength. In these IR wavelengths, the Webb pwn3z!!!11!! Hubble but only at those wavelenghts. If you wan't to view something green or in the UV, you're out of luck with Webb. Although I believe that one of the other current telescopes can see some UV, we've got a huge gap in out observing capabilities with no Hubble.
Furthermore, There's no guarantee that the Webb will work. It's going up on an Arianne 5 which blows up with distressing regularity. The Webb uses an untested folding mirror - what if it pulls a Gallileo and the mirror doesn't deploy? It's not like we can go and fix it at L2 or anything.
Furthermore, the optics in Hubble are still just fine. It's got problems with failing gyroscopes which would have been replaced with the cancelled repair. Furthermore, the new cameras (which are already completed and cost us $400 million, BTW) upgrade Hubble to the point where it's as good as any of the new telescopes we've lofted, short of a larger aperture size.
It's not like we throw out the Keck because a new CCD camera comes our - we use the same optics and throw in a new camera assembly. The cancelled Hubble mission is just like that - the Hubble optics are still just fine. There's no reason that we can't take that 18 years and extend it another 8-10 with the servicing mission.
OK, I've posted this same message, like 10 times, already in this discussion and I'm starting to feel like a Spam-bot or something. I want to make sure people read this, though.
Leaked NASA documents (you can see them at the Mars Society web page) show that Hubble is no more dangerous than going to ISS. In fact, the high orbital inclination of ISS probably makes it more dangerous to get to. If this were actually an issue of astronaut safety, I'd be applauding NASA for making the right decision. However, this is clearly a politically motivated move to save money for the ISS.
No argument about Webb being tecnically superior to Hubble. However, there's two problems.
1: as the other reply mentions, Webb can't do green to UV measurements. Ground based telescopes lack the ability to do good UV measurements due to atmospheric absorbtion. There's still plenty of stuff that astronomers want to do in those wavelenghts.
2: The Webb isn't up and running. What if that Ariane 5 blows up like they seem to be prone to do? What if the mirror doesn't deploy properly? The folding mirror has never been operationally tested - we never did conclusively figure out why Gallileo's main antenna didn't deploy - what if Webb does the same? What if the cryogenic dewar springs a leak or outgasses faster than anticipated? What if any number of a million possible things go wrong and the Webb doesn't work We can't fix it at L2 so we're now stuck with a dead telescope. We should at least keep Hubble running until Webb is properly running.
As I and some others have pointed out, the ISS is actually riskier to get to because of it's high orbital inclination. As it is, Hubble needs a single servicing mission at a 2% risk which is the same now as it was before either Columbia or Challenger. Docuents leaked from NASA confirm this. I have no problem letting Hubble die if it actually does pose a threat to astronauts but this is a purely politically motivated move.