NeoCode writes: "It's been 11 years already and the stats are mind boggling. Hubble is celebrating its 11th birthday and it sent another beautiful image. Stories here (CNN) and here (Space). A lot of these images have been called "space-art". The image bank can be found here."
Re:Science is simply faith
by
phil+reed
·
· Score: 2
What if light slowed down away from the earth?
What if monkeys flew out of my butt? If you can get away from the earth and test this presumption, that would be one thing.
As it turns out, this proposal is testable. The speed of light is controlled by two fundamental variables - the permissivity and permittability of free space (I think I've got these names right). These variables control other things as well, such as the binding energy between electrons and the nucleus of an atom. We can measure that binding energy by looking at atomic absorption and emission lines in spectra of far-off stars. Those lines are the same as we see on earth, therefore we conclude that the fundamental variables have the same value there as here, therefore we can conclude the speed of light is the same there as here.
Therefore we conclude the objection about a varying speed of light is bogus and can be discarded, along with all the predictions it makes.
...phil
--
...phil "For a list of the ways which
technology has failed to improve our quality of life, press
3."
Re:Is Hubble So useful? Adaptive optics is cheaper
by
RayChuang
·
· Score: 2
While using adaptive optics helps reduce the effects of the atmosphere, it's still not going to completely negate the effects of water vapor, dust and pollution particles.
Remember, the Next Generation Space Telescope will operate at the same altitude as Hubble--350 to 400 miles off the ground, which eliminates the atmospheric effects from the particles I mentioned above. For example, could you have been able to get those astonishing pictures from the Eagle Nebula from ground-based telescopes? I don't think so.:-) And only Hubble could see the numerous galaxies at a supposedly dark part of the sky that ground-based observers noted.
-- Raymond in Mountain View, CA
Re:The largest waste of my money
by
RayChuang
·
· Score: 3
If I could moderate I'd mod you down to troll status.:-)
The thing about Hubble--epecially since COSTAR was installed--is that it offers extremely sharp pictures you'll never see on a ground-based telescope, even with the new telescopes going up at Mauna Kea in Hawaii and the European Southern Observatory in Chile.
The reason is simple: no atmospheric interference. Even at the high altitudes of the ground observatories I mentioned, you still have a lot of atmosphere to contend with.
Why do you think both NASA and ESA are on a fairly fast track to build more powerful space telescopes that will be launched starting late this decade?
-- Raymond in Mountain View, CA
Re:The largest waste of my money
by
JJ
·
· Score: 2
The Hubble is by far the most powerful telescope advance in the history of astronomical observations. And your estimate of "not only did it cost billions of dollars before it was even launched" is just plain wrong. While expensive, it cost no more than the Palomar observatory cost in constant dollars. It's operation costs are very reasonable and any astronomer who has ever seen pictures from it will inform you that it is the best investment we could have made. While Hubble initially did initially have a problem with its focus, it was still working and the array of instruments on board allowed observations to be made continuously.
The Hubble has been an incredible success, is an exemplar of government sponsored science at reasonable cost.
-- So long and thanks for all the fish . . . !!!
Re:Shame it only sees an illusion.
by
Y-Leen
·
· Score: 2
get even better
pictures soon...
You got it! The link in the story doesn't give show all the images (just the latest HH Neb.). There is a complete image collection here. Enjoy.
Re:Wow... Just pause a moment and take it all in.
by
cowscows
·
· Score: 2
I'll definately agree that space is full of fascinating things, and I'm all for the exploration of space, but come on, maybe you should get off of your computer and go outside a little more often. The trees and mountains and rivers and animals are every bit as beautiful and interesting, and they're just a little more accecssible.
The sad thing about it is, taking money from the space program probably does not benefit the health of the earth very much. Infact, the space program is responsible for much of the knowledge of the earth that we have. A lot of the current ecological buzzwords that people are worrying about are considered 'global issues', and where else can you observe the globe as one big object than from space?
oh, and on a side note, the CNN page linked about it had a little box with the 'hubble top ten', the first one of which was about hubble's view of Jupiter getting attacked by the shoemaker-levy comet, and it talked about how great a view hubble had. I just had to say that the picture they included with it was absolutely awful. I haven't really done any searching for images, but I hope hubble got a few better than the one that CNN just showed me.
--
One time I threw a brick at a duck.
Re:Is Hubble So useful? Adaptive optics is cheaper
by
mattorb
·
· Score: 2
If all you cared about was image resolution, then sure, AO would be great. But you're neglecting a much more fundamental limitation of graound-based astronomy, which is that the Earth's atmosphere is quite opaque over large regions of wavelength space -- that is, you just can't observe in, say, the far ultraviolet from the ground, because you can't see through the atmosphere.
Of course, this is an argument for space-based missions generally, not HST specifically. But still, Hubble is a great orbiting platform with unbelievably good pointing (amazing what you can do with a few billion dollars), whose general operational procedures / problems are well understood. Contrast this with a new satellite system, built from the ground up.
Note, also, that great things are still in the cards for Hubble -- eg the Cosmic Origins Spectrograph, which will be installed onboard in a couple years. So it's not just decades-old technology that has since been superseded by ground-based stuff...
Actually, the real image bank can be found here. It's got a lot of image series neatly lined up. The link in the story only shows the last (Horsehead Nebula) series.
And its done all this...
by
randomErr
·
· Score: 2
And its done all this with a set of corrective lenses. Lets hear it for glasses!
-- You say things that offend me and I can deal with it. Can you?
"Hubble was launched by the shuttle Discovery on April 24, 1990. Two days later, the telescope was on its own, drifting into space, recording cosmic images."
"On its own, drifting into space, the Hubble space telescope is a reckless, lone rebel without a cause."
Then the universe would be even older than the 15-20 billion years it appears to be.
Thus the universe's age is in reality not established AT ALL, not that scientists can agree on that either!
Observation: some scientists think the universe is fifteen billion years old.
Observation: other scientists think the universe is twenty billion years old.
shadrax's conclusion: Scientists can't agree on the age of the universe; therefore the universe might actually be six thousand years old.
I can't help but wonder: when shadrax sees an old man on the street, and can't decide whether the man is closer to seventy or eighty, does shadrax conclude that the man might actually be five?
Scientists use circular logic. For example, a dinosaur bone might be dated to x million years old. So we've disproved the Bible--or have we? How do biologists know what level of carbon dating is how old? Well, the geologist over there says the rock it was found in is x million years old. So ask the geologist how he knows how old the rock is. Well, of course, fossils just that old happen to be found there, so of course the rock is that old!
This would be a valid argument if radiometric dating measured only two isotopes. By using isochron methods, which require three isotopes, the age of materials can be determined radiometrically without the sort of circular reasoning shadrax describes.
Not to mention that shadrax is apparently unaware that carbon dating is only good for dates up to tens of thousands of years (carbon dating is only one type of radiometric dating; others are good for much larger ages). Also, carbon dating has been validated by non-radiometric methods, such as counting tree rings or ice layers.
Scientists insist that cave and rock formations must have been formed over millions of years. They have never considered the possible effect of a single catastrophic event, such as the Flood, in creating rock formations like the Grand Canyon.
Never take moderation advice from sigs, including this one.
Re:Shame it only sees an illusion.
by
aussersterne
·
· Score: 2
NASA is willing to spend billions on these high tech toys, and nothing at all on discovery of ancient relics.
Yeah, I'd much rather have a shattered old clay pot with some leftover "Jesus" dandruff in it than all of these images of the vastness of creation in all its glory.
What are they thinking, dabbling in all this stuff, so clearly shallow and frivolously pretty?
(I can't figure out whether you're joking or serious, but I hope to god you're not serious...)
-- STOP . AMERICA . NOW
Wow... Just pause a moment and take it all in.
by
aussersterne
·
· Score: 2
Thank you Hubble.
And thank you, Slashdot for posting the link to the image archive. It has made my day. It's when I see things like this that I realize how much I miss the "space race" and everything it brought with it.
I know that it's important to save the trees and everything else here on Earth, but I'll be damned if space isn't just a whole hell of a lot prettier anyway, and spaceships and aliens a whole hell of a lot more fun.;^)
We- STScI, not NASA- are currently migrating the Archive from 12-inch optical media (6GB/platter) to 5.25-inch magneto-optical media (5.2GB/platter, but looking to upgrade to 9.1 next year). In FY02 we want to find a good way of caching the data for distribution on magdisk, to cut down on our reliance on jukeboxes. We're required to keep a permanent version, though, so we'll still write MOs.
Also, we don't actually store 6TB. For the currently operating instruments (WFPC2 & STIS, but not FOC, which doesn't get used much any more), we don't store the calibrated data; we calibrate it on the fly when it's retrieved. We're just now getting ready to take that back a step: we won't even store the uncalibrated data, just the very raw data from the telescope, before it's broken out into FITS files. This will then be turned into uncalibrated data, calibrated, and the result sent to the user (On-the-fly Reproecssing, OTFR). With OTFR, I think we'll actually be storing somewhere between 1 and 2 TB, including the engineering data. OTFR will also apply to future instruments, like ACS and NICMOS (when the latter gets turned back on).
Tim Kimball//
Archive Systems Analyst II//
Space Telescope Science Institute
-- Exit, pursued by a bear.
Higher quality, higher res pics available
by
Joe+Hardy+(_yoda)
·
· Score: 3
If you want to have a look at the same pic at *much* higher resolutions than the linked site offers, check out NOAO's great image gallery here.
The rest of the gallery is worth looking at as well.
Traveled more than 1.6 billion miles (2.6 billion km)
Made more than 400,000 exposures
Observed 15,000 astronomical targets
Downloaded more than 6 terabytes of data
6 terabytes worth of info is certainly a lot of shit to store. I wonder whats NASA using for storage, certainly isn't a Netapp. Clariion? S'more than my whole company.
Happy Birthday telescope thingy.
"Neither in French nor in English nor in Mexican." George W. Bush declining to answer reporters' questions at the Summit of the Americas, Quebec City, Canada, April 21, 2001
Is Hubble So useful? Adaptive optics is cheaper
by
linca
·
· Score: 2
Well, Hubble is a great project that brings us nice images of the space and etc..., but it is now outdated technology.
with the advent of
adaptive optics It is now easy to get images as neat as those photographied by Hubble, and even better, from the earth.
The advantages being that since it is based on the ground, it is much, much cheaper. No need to send Shuttles in the space or on the moon... Of course it is less spectacular, but it is better for Science. It is currently being installed on the European Space observatory at least.
So Hubble is quite old enough...
This technology supresses the effect of the atmosphere by mesuring the noise it produces and cancelling it. It is explained on the link...
Re:Is Hubble So useful? Adaptive optics is cheaper
by
pavonis
·
· Score: 4
Well, AO in optical wavelengths is still an immature technology, in the sense that every rigup is rather unique and experimental. It's only become really usable at all in the last year or so. And it's quite expensive too, though admittedly less so than Hubble.
It's a wonderful use of technology, and a terrific example of wholly separate fields of science aiding each other; but it's not the endall to telescopes, either. Space scopes have a number of advantages over even the best ground-based telescopes, like ESO and Keck-
You need to build a bigger scope on the ground to get the same amount of light, due to atmospheric lossage. Admittedly it's relatively easy to build big scopes on the ground.
Hubble can look at (almost) any target at any time, 24 hours a day, and it never rains up there. This means that in sheer amount of observing done, it needs to be compared to at least 3 telescopes, not just one.
Good sites for ground telescopes are in increasingly short supply, as cities spread around the world. Many, for instance, now take sites in the Chilean Andes that are about as hard to get to, and work from, as any place on Earth. That ends up costing quite a bit, too.
No ground-based scope can ever take an exposure lasting more than maybe eight hours. The Deep Field would be impossible to ever do on Earth. And the effectiveness of AO declines the longer your exposure, of course.
While, tragically, launch prices are not coming down much yet, we can at least imagine that eventually they will, and space telescopes will be cheaper.
It would be very hard, maybe impossible, to do long-baseline optical interferometry on Earth, because of things like ground tremors. It may be possible to use baselines miles long in space. This would utterly change the face of astronomy. The first test will be NASA's Terrestrial Planet Finder, sometime this decade. For optical interferometry, see Keck's web site- here.
Hubble's successor, the NGST, will actually be a near-infrared telescope. Light from very distant objects is red-shifted all the way into the infrared, so NGST will be optimized for this kind of large-scale, cosomological research. This is hard to do from the ground, as the atmosphere is a tremendous source of infrared noise even at night in cold places.
So while AO is extremely valuable, I don't think any astronomer is prepared to say "Okay, let's ditch the space telescopes now." And if you can launch them working right the first time, and don't have to foot the bill for shuttle repair missions, they are not so expensive as most folks here seem to think.
Re:the future of our eyes
by
Spagornasm
·
· Score: 3
There's a process called "interferometry." It is the combining of several smaller telescopes along the exact curvature of a larger one to produce a similar effect to the larger one. Anyone seen Contact? The VLA(where Jodie Foster heard that signal), or Very Large Array, is a series of radio telescopes layed out over almost a mile (I think) in a big peace sign. They can gather the same kind of information that a single, unimaginably more expensive telescope could.
The reason we don't have these large arrays of optical telescopes has to do with the nature of light. Radio waves have such a large wavelength that aligning several telescopes along the exact parabolic curve of a simulated large reflector is not difficult (radio waves can be anywhere from several inches to several hundred feet long).
An optical telescope array presents a much more difficult problem. Light in the visible spectrum has very small wavelengths (less than an inch). Thus, aligning even two telescopes along the proper parabolic curve for interferometry is extraordinarily difficult on earth. People are trying this with the twin 10 meter Keck telescopes in Hawaii, though, and have met with some success. The easiest place for interferometry, though, is space.
There are actually plans in NASA (I don't know if Daniel Goldin has cancelled this yet) for a few new space telescopes.
The first one is the NGST, or Next Generation Space Telescope. This will have a large solar shield (basically, a large sheet of mylar to reflect heat away from the mirrors). It will have several octagonal mirror surfaces, and will unfold to be about 8 meters across (Hubble is less than 3). It will also have various infrared and microwave cameras built in, so dangerous "upgrade" missions won't be required nearly as much.
A more long-term telescope project is under way to actually image earth-sized planets. The first will be a series of two or three small telescopes orbiting between Earth and Mars. These will be testing laser tracking and micro-rocket stability systems, and will atempt to keep the telescopes perfectly aligned down to the micrometer.
If this is successful, then a few years later a couple of telescopes the size of NGST (this is into the 2010's) will be launched and aligned in a similar manner beyond Jupiter (the plan is to spread them over about 300 meters. Imagine that - a 300 meter wide telescope, in space, without any of the distortions our atmosphere provides!). This will allow them not only an unprecedented clarity (one of the main reasons Hubble can take such amazing pictures), but also size (it could theoretically see back to half a million years after the Big Bang), and it could, of course, resolve a visual image of an earth-like planet.
Such a telescope could take the spectra of such planets. A spectrum is the rainbow you see when white light is shone through a prism. When light bounced off a certain substance is analyzed, there are dark bars present, that can tell a scientist precisely what elements (and how much of each) are present. Sometimes, in labs, scientists will burn a chunk of material with a laser, and record that (it's much brighter), but astronomers can do it with telescopes. This means that astronomers, from light years away, could tell if a planet had liquid water, oxygen, nitrogen, methane, sulfur, whatever. It is, however, highly unlikely that such a telescope could see lights at night. For one thing, it's not a given that any species would even NEED light (or that if we could detect civilization from so far away, why wouldn't we also be recieving radio or maser signals from them?). For another, just when it would be possible to see the dark side of that planet would be when it is silhouetted against its sun (imagine trying to read the date off of a dime a thousand miles away when it's held in front of a 4D flashlight).
Even further down the road (like approaching 2100) is the idea of a gravity telescope. These would be several dozen AU away (an AU, or Astronomical Unit, is the average distance from Earth to the sun, or 93,000,000 miles). These telescopes would take advantage of the fact that gravity bends light (if you ever look at some of the deep space images that the large telescopes have taken, you can see large arcs, and what look like misplaced images. These are the images of galaxies that have been bent, distorted, or magnified by either another galaxy or galaxy cluster between it and us). These gravity telescopes would be placed exactly where the gravity of the sun focuses light to a point, and thus be able to see simply unbelievable amounts of the universe. Even one of these, sweeping through a tiny arc of its several hundred year orbit, would quickly amass more information than NASA is currently capable of storing.
All in all, though, there is so much left to learn from deep space, it almost makes you cry. I find the whole endeavor rather exciting.
--
When nuance becomes the only objective we lose the ability to function
Slashdot Mirror
What if monkeys flew out of my butt? If you can get away from the earth and test this presumption, that would be one thing.
As it turns out, this proposal is testable. The speed of light is controlled by two fundamental variables - the permissivity and permittability of free space (I think I've got these names right). These variables control other things as well, such as the binding energy between electrons and the nucleus of an atom. We can measure that binding energy by looking at atomic absorption and emission lines in spectra of far-off stars. Those lines are the same as we see on earth, therefore we conclude that the fundamental variables have the same value there as here, therefore we can conclude the speed of light is the same there as here.
Therefore we conclude the objection about a varying speed of light is bogus and can be discarded, along with all the predictions it makes.
...phil
...phil
"For a list of the ways which technology has failed to improve our quality of life, press 3."
While using adaptive optics helps reduce the effects of the atmosphere, it's still not going to completely negate the effects of water vapor, dust and pollution particles.
:-) And only Hubble could see the numerous galaxies at a supposedly dark part of the sky that ground-based observers noted.
Remember, the Next Generation Space Telescope will operate at the same altitude as Hubble--350 to 400 miles off the ground, which eliminates the atmospheric effects from the particles I mentioned above. For example, could you have been able to get those astonishing pictures from the Eagle Nebula from ground-based telescopes? I don't think so.
Raymond in Mountain View, CA
If I could moderate I'd mod you down to troll status. :-)
The thing about Hubble--epecially since COSTAR was installed--is that it offers extremely sharp pictures you'll never see on a ground-based telescope, even with the new telescopes going up at Mauna Kea in Hawaii and the European Southern Observatory in Chile.
The reason is simple: no atmospheric interference. Even at the high altitudes of the ground observatories I mentioned, you still have a lot of atmosphere to contend with.
Why do you think both NASA and ESA are on a fairly fast track to build more powerful space telescopes that will be launched starting late this decade?
Raymond in Mountain View, CA
The Hubble is by far the most powerful telescope advance in the history of astronomical observations. And your estimate of "not only did it cost billions of dollars before it was even launched" is just plain wrong. While expensive, it cost no more than the Palomar observatory cost in constant dollars. It's operation costs are very reasonable and any astronomer who has ever seen pictures from it will inform you that it is the best investment we could have made. While Hubble initially did initially have a problem with its focus, it was still working and the array of instruments on board allowed observations to be made continuously.
The Hubble has been an incredible success, is an exemplar of government sponsored science at reasonable cost.
So long and thanks for all the fish . . . !!!
You got it! The link in the story doesn't give show all the images (just the latest HH Neb.). There is a complete image collection here. Enjoy.
The sad thing about it is, taking money from the space program probably does not benefit the health of the earth very much. Infact, the space program is responsible for much of the knowledge of the earth that we have. A lot of the current ecological buzzwords that people are worrying about are considered 'global issues', and where else can you observe the globe as one big object than from space?
oh, and on a side note, the CNN page linked about it had a little box with the 'hubble top ten', the first one of which was about hubble's view of Jupiter getting attacked by the shoemaker-levy comet, and it talked about how great a view hubble had. I just had to say that the picture they included with it was absolutely awful. I haven't really done any searching for images, but I hope hubble got a few better than the one that CNN just showed me.
One time I threw a brick at a duck.
Of course, this is an argument for space-based missions generally, not HST specifically. But still, Hubble is a great orbiting platform with unbelievably good pointing (amazing what you can do with a few billion dollars), whose general operational procedures / problems are well understood. Contrast this with a new satellite system, built from the ground up.
Note, also, that great things are still in the cards for Hubble -- eg the Cosmic Origins Spectrograph, which will be installed onboard in a couple years. So it's not just decades-old technology that has since been superseded by ground-based stuff...
Actually, the real image bank can be found here. It's got a lot of image series neatly lined up. The link in the story only shows the last (Horsehead Nebula) series.
And its done all this with a set of corrective lenses. Lets hear it for glasses!
You say things that offend me and I can deal with it. Can you?
"Hubble was launched by the shuttle Discovery on April 24, 1990. Two days later, the telescope was on its own, drifting into space, recording cosmic images."
"On its own, drifting into space, the Hubble space telescope is a reckless, lone rebel without a cause."
Who said anything about atheism? There are many Christians who accept evolution. Acceptance of evolution != atheism.
Never take moderation advice from sigs, including this one.
Yet a closer examination reveals that "science" is little more than a separate religion itself.
Is evolution just another religion?
Evolution cannot be observed.
Observed instances of speciation
What if light slowed down away from the earth?
Then the universe would be even older than the 15-20 billion years it appears to be.
Thus the universe's age is in reality not established AT ALL, not that scientists can agree on that either!
Observation: some scientists think the universe is fifteen billion years old.
Observation: other scientists think the universe is twenty billion years old.
shadrax's conclusion: Scientists can't agree on the age of the universe; therefore the universe might actually be six thousand years old.
I can't help but wonder: when shadrax sees an old man on the street, and can't decide whether the man is closer to seventy or eighty, does shadrax conclude that the man might actually be five?
Scientists use circular logic. For example, a dinosaur bone might be dated to x million years old. So we've disproved the Bible--or have we? How do biologists know what level of carbon dating is how old? Well, the geologist over there says the rock it was found in is x million years old. So ask the geologist how he knows how old the rock is. Well, of course, fossils just that old happen to be found there, so of course the rock is that old!
This would be a valid argument if radiometric dating measured only two isotopes. By using isochron methods, which require three isotopes, the age of materials can be determined radiometrically without the sort of circular reasoning shadrax describes.
Not to mention that shadrax is apparently unaware that carbon dating is only good for dates up to tens of thousands of years (carbon dating is only one type of radiometric dating; others are good for much larger ages). Also, carbon dating has been validated by non-radiometric methods, such as counting tree rings or ice layers.
Scientists insist that cave and rock formations must have been formed over millions of years. They have never considered the possible effect of a single catastrophic event, such as the Flood, in creating rock formations like the Grand Canyon.
Problems with a Global Flood: Producing the Geological Record
Never take moderation advice from sigs, including this one.
NASA is willing to spend billions on these high tech toys, and nothing at all on discovery of ancient relics.
Yeah, I'd much rather have a shattered old clay pot with some leftover "Jesus" dandruff in it than all of these images of the vastness of creation in all its glory.
What are they thinking, dabbling in all this stuff, so clearly shallow and frivolously pretty?
(I can't figure out whether you're joking or serious, but I hope to god you're not serious...)
STOP . AMERICA . NOW
Thank you Hubble.
;^)
And thank you, Slashdot for posting the link to the image archive. It has made my day. It's when I see things like this that I realize how much I miss the "space race" and everything it brought with it.
I know that it's important to save the trees and everything else here on Earth, but I'll be damned if space isn't just a whole hell of a lot prettier anyway, and spaceships and aliens a whole hell of a lot more fun.
STOP . AMERICA . NOW
We- STScI, not NASA- are currently migrating the Archive from 12-inch optical media (6GB/platter) to 5.25-inch magneto-optical media (5.2GB/platter, but looking to upgrade to 9.1 next year). In FY02 we want to find a good way of caching the data for distribution on magdisk, to cut down on our reliance on jukeboxes. We're required to keep a permanent version, though, so we'll still write MOs.
Also, we don't actually store 6TB. For the currently operating instruments (WFPC2 & STIS, but not FOC, which doesn't get used much any more), we don't store the calibrated data; we calibrate it on the fly when it's retrieved. We're just now getting ready to take that back a step: we won't even store the uncalibrated data, just the very raw data from the telescope, before it's broken out into FITS files. This will then be turned into uncalibrated data, calibrated, and the result sent to the user (On-the-fly Reproecssing, OTFR). With OTFR, I think we'll actually be storing somewhere between 1 and 2 TB, including the engineering data. OTFR will also apply to future instruments, like ACS and NICMOS (when the latter gets turned back on).
Tim Kimball //
Archive Systems Analyst II //
Space Telescope Science Institute
Exit, pursued by a bear.
If you want to have a look at the same pic at *much* higher resolutions than the linked site offers, check out NOAO's great image gallery here.
The rest of the gallery is worth looking at as well.
-- No, no gems to be found in this sig.
Orbited Earth 60,000 times
Traveled more than 1.6 billion miles (2.6 billion km)
Made more than 400,000 exposures
Observed 15,000 astronomical targets
Downloaded more than 6 terabytes of data
6 terabytes worth of info is certainly a lot of shit to store. I wonder whats NASA using for storage, certainly isn't a Netapp. Clariion? S'more than my whole company.
Happy Birthday telescope thingy.
"Neither in French nor in English nor in Mexican." George W. Bush declining to answer reporters' questions at the Summit of the Americas, Quebec City, Canada, April 21, 2001
Lone Gunman
360 degrees of Karma
har har
360 degrees of Karma
Well, Hubble is a great project that brings us nice images of the space and etc..., but it is now outdated technology. with the advent of adaptive optics It is now easy to get images as neat as those photographied by Hubble, and even better, from the earth.
The advantages being that since it is based on the ground, it is much, much cheaper. No need to send Shuttles in the space or on the moon... Of course it is less spectacular, but it is better for Science. It is currently being installed on the European Space observatory at least.
So Hubble is quite old enough... This technology supresses the effect of the atmosphere by mesuring the noise it produces and cancelling it. It is explained on the link...The reason we don't have these large arrays of optical telescopes has to do with the nature of light. Radio waves have such a large wavelength that aligning several telescopes along the exact parabolic curve of a simulated large reflector is not difficult (radio waves can be anywhere from several inches to several hundred feet long).
An optical telescope array presents a much more difficult problem. Light in the visible spectrum has very small wavelengths (less than an inch). Thus, aligning even two telescopes along the proper parabolic curve for interferometry is extraordinarily difficult on earth. People are trying this with the twin 10 meter Keck telescopes in Hawaii, though, and have met with some success. The easiest place for interferometry, though, is space.
There are actually plans in NASA (I don't know if Daniel Goldin has cancelled this yet) for a few new space telescopes.
The first one is the NGST, or Next Generation Space Telescope. This will have a large solar shield (basically, a large sheet of mylar to reflect heat away from the mirrors). It will have several octagonal mirror surfaces, and will unfold to be about 8 meters across (Hubble is less than 3). It will also have various infrared and microwave cameras built in, so dangerous "upgrade" missions won't be required nearly as much.
A more long-term telescope project is under way to actually image earth-sized planets. The first will be a series of two or three small telescopes orbiting between Earth and Mars. These will be testing laser tracking and micro-rocket stability systems, and will atempt to keep the telescopes perfectly aligned down to the micrometer.
If this is successful, then a few years later a couple of telescopes the size of NGST (this is into the 2010's) will be launched and aligned in a similar manner beyond Jupiter (the plan is to spread them over about 300 meters. Imagine that - a 300 meter wide telescope, in space, without any of the distortions our atmosphere provides!). This will allow them not only an unprecedented clarity (one of the main reasons Hubble can take such amazing pictures), but also size (it could theoretically see back to half a million years after the Big Bang), and it could, of course, resolve a visual image of an earth-like planet.
Such a telescope could take the spectra of such planets. A spectrum is the rainbow you see when white light is shone through a prism. When light bounced off a certain substance is analyzed, there are dark bars present, that can tell a scientist precisely what elements (and how much of each) are present. Sometimes, in labs, scientists will burn a chunk of material with a laser, and record that (it's much brighter), but astronomers can do it with telescopes. This means that astronomers, from light years away, could tell if a planet had liquid water, oxygen, nitrogen, methane, sulfur, whatever. It is, however, highly unlikely that such a telescope could see lights at night. For one thing, it's not a given that any species would even NEED light (or that if we could detect civilization from so far away, why wouldn't we also be recieving radio or maser signals from them?). For another, just when it would be possible to see the dark side of that planet would be when it is silhouetted against its sun (imagine trying to read the date off of a dime a thousand miles away when it's held in front of a 4D flashlight).
Even further down the road (like approaching 2100) is the idea of a gravity telescope. These would be several dozen AU away (an AU, or Astronomical Unit, is the average distance from Earth to the sun, or 93,000,000 miles). These telescopes would take advantage of the fact that gravity bends light (if you ever look at some of the deep space images that the large telescopes have taken, you can see large arcs, and what look like misplaced images. These are the images of galaxies that have been bent, distorted, or magnified by either another galaxy or galaxy cluster between it and us). These gravity telescopes would be placed exactly where the gravity of the sun focuses light to a point, and thus be able to see simply unbelievable amounts of the universe. Even one of these, sweeping through a tiny arc of its several hundred year orbit, would quickly amass more information than NASA is currently capable of storing.
All in all, though, there is so much left to learn from deep space, it almost makes you cry. I find the whole endeavor rather exciting.
When nuance becomes the only objective we lose the ability to function