dalutong writes "BBC News has an article detailing NASA's replacement for the much-loved Hubble telescope. The $4.5 billion telescope will be placed in orbit 1.5 million km from Earth and will be almost three times the size of the Hubble. It is set to launch in 2013. They also plan to service the Hubble in 2008."
I recall that the Orion program which is currently under development will have the capability to do the job. It is slated to replace the shuttle and also have the ability to reach the moon. One of the goals was to be able to do a service mission of the JWT far far away. More info here. http://www.nasa.gov/mission_pages/constellation/ma in/index.html/ [nasa.gov]
Ground based telescopes are good only for light that is not filtered by the atmosphere. There is a whole lot of spectrum outside it. The JWST targets the infra-red wavelengths, which would be much harder to do with an atmosphere above it
In addition to what the poster above me says about the atmosphere and spectrum of light, I'd like to point out...
$5 Billion dollars DOES seem like a lot. But look at the U.S. Budget in the last decade. Look at the money we've essentially THROWN AWAY. By comparison, $5 billion for an advancement of science seems rather reasonable, or at the very least, reasonable by comparison.
The average cost of each war the US engages in ends up being around $600 billion (after adjusting each one for inflation). We'll just have to complete the next war in 119/120ths of the time and the cost of the new telescope is covered:)
Although it will see further than Hubble, JWST will see infrared, so that we still need Hubble for the visible and ultraviolet.
An servicing the Hubble is judged to be so risky that NASA originally did not plan to do it. Now they intend to do it, but with a backup shuttle in orbit in case the first one gets into trouble.
JWST will provide diffraction-limited images at 2 micron. It will have imaging and spectrographic capabilities in the near and mid-IR -- everything from 6000AA out to 27micron with the mid-IR imager and spectrograph (MIRI). StSci has a JWST primer online here [stsci.edu] (pdf link).
The imaging will be near infrared with particular capability near 2 microns, but the 5 micron capability is alos of interest. There is also a smaller camera working from 5 to 27 microns. This is mid-infrared. The resolution of this instrument will not be so good because of the longer wavelength. The Keck Telescope can get better image quality. But what it will have is spectroscopic capability and much greater sensitivity. We've gotten quite alot of milage out of the much smaller Spitzer Space Telescope using it's 5--30 micron spectrograph. This new instrument should really open things up, allowing us to analyse stars in galaxies as they were when the universe was 12 billion years younger. All telescopes can be considered time machines, but this one is made to see some of the very first stars. You can read more about it here: http://www.stsci.edu/jwst/instruments/ [stsci.edu]. -- Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html [blogspot.com]
If all the money and drama of NASA produced nothing but Hubble it has been worth it. NASA is billing JWST as Hubble's replacement. Is it? Really? Honestly?
You know, to me, NASA could do nothing but produce obscure scientific data that I would never comprehend, but I'd still support them spending my tax dollars more than the fuckers who waste my money on war. $4.5 billion for a precision scientific instrument is money well spent. $4.5 billion for waging war and murdering your fellow human beings is absolutely criminal.
While difficult, its much cheaper and easier to get hubble-style resolution in the optical range from ground. Dont forget that "hugely expensive" for a ground telescope is compareable to "dirt-cheap" for a space-based one. All 4 of the VLT telescopes were (IIRC) cheaper than a single hubble service mission. And OWL should be compareable to a modern space-telescope, too, for a fraction of the price (dont forget: its a tradeoff: better seeing vs "have to design a mirrror that can withstand the acceleraion and f
Your cost estimates are accurate, but the rest of your argument is total shit. Adaptive optics, WHEN it works (which is rarely, and with difficulty), can approach the angular resolution of HST in a VERY SMALL field of view. You cannot get 0.05 arcsec, diffraction limited images over a wide field of view, that is possible with HST.
"Designing a mirror to withstand a launch vehicle" is a problem that has been solved. And the only two current, viable telescope proposals for telescopes larger than 10m are the Thirty Metre Telescope (TMT [tmt.org]) and the Giant Magellan Telescope (GMT [gmto.org]). OWL is not a concept that is being taken very seriously...ESO certainly hasn't put its money where its mouth is.
Your final point, about not many lines in that part of the spectrum, belies a complete lack of understanding of what you are talking about. The UV (accessible with STIS, and the Cosmic Origins Spectrograph, which will fly on SM4 in late '08) are so full of lines that they overlap all over the place. See, for example, Morton (2003), ApJS, 149, 205, for a comprehensive list. At low redshift, lines of HI, OI, OVI, CIV, NV, CII, SiII, SII, FeII, NI...all are in the UV, in the STIS band. Furthermore, space is the ONLY place these wavelengths can be observed, because of the atmosphere is opaque to wavelengths shorter than about 3300 angstroms.
"Now they intend to do it, but with a backup shuttle in orbit in case the first one gets into trouble."
That would be retarded; the most dangerous phases of the mission are launch and reentry, with a significantly lower risk of something going wrong while in orbit; something likely to either be so terrible you can't do anything or managable enough that you have a good long while to worry about it (e.g one of the tiles gets damaged at launch and you can't reenter safely, ala Columbia).
So no, it won't be in orbit, the backup shuttle will simply be ready to launch if needed.
Unfortunately you beat me to the punch on this one, I spent to much time double checking flight numbers and which OV's were going to be used. Sadly enough I use Wikipedia. I can't find shit on the NASA site half the time
but with a backup shuttle in orbit in case the first one gets into trouble.
Can you please site a source for this? Right now the software cannot actually support more than one shuttle in orbit at a time, if you look there has never been more than one up at a time. If there were this type of upgrade coming I could buy that story, but considering we're going to retire the fleet soon I don't see that as likely. I haven't installed any Aries specific equipment yet, but judging by the age of most of the shuttle specific equipment on the ground they're not going to do that level of a software rewrite for the shuttle when the fleets this close to retirement. Another issue with this statement is the shear altitude of the Hubble, well above ISS orbit. If we launched one into high orbit, and kept one at low orbit the one in low orbit simply wouldn't be able to reach the one in high orbit without landing for fuel anyways. Those things launch with their trajectories pretty much set and only do slight manuvering. STS-125 is the designated flight for Hubble servicing to be done by Atlantis, there is an as yet unnumbered contingency rescue flight, I don't think they number those unless they launch these days. They may put Discovery on the pad in ready position for rescue, but I seriously doubt they'll launch it unless they have to.
On another note: There are emergency two shuttle protocols. What that comes down to more or less is equipment time sharing.
I was quite the fervent supporter of the Hubble up until I attended a talk by Dr. Philip Stahl, from the Marshall Space Center, and optics technical lead on the new James Webb Space Telescope.
Yes, the JWST is an infrared telescope. But, as another post further down alludes to incorrectly (for which they were smacked down and corrected by someone else) the James Webb is able to see further back into the history of the universe than we have ever been able to observe. What started out as visible light all those billions of years ago (and billions of light years away) becomes red-shifted into the infrared as the universe expands and, in a nearly literal fashion, stretches out that incoming light.
So while the Hubble has been responsible for a lot of great science, and truly breath-taking images, we have the potential to do so much more and better understand our universe with the JWST. We haven't maxed out the potential of the Hubble (probably never would), and I would love to keep it, but if there's only enough to deploy the JWST (and it's already been pushed back by several years), or keep on servicing the Hubble, my vote would be in favour of the JWST.
The age of precision cosmology is a relative term. This mission will make precision astrometry so good its a little scary. But, I do like mid-infrared so I like JWST.
It is expected to be launched by the ESA in the second half of 2011, and will be operated in a Lissajous orbit around the Sun-Earth L2 Lagrangian point.
Let's hope they will agree on non-intersecating orbits for Gaia and JWST.
Gaia team: Hey! We were here first! JWST team: "Here"? You are oscillating all around the place! Gaia team: Ours is an elegant Lissajous orbit. What is yours? JWST team: We'll pwn the L2 point itself! Gaia team: No way! Our probe will intersect it in 13 days. JWST team: Metric days or imperi
As radiation travels from distant stars and passes through obstacles, gravitational lensing, dust clouds, etc., it loses energy and thus frequency eventually turning radiation from the gamma/x-ray spectrum into visible light then into infrared light. This new telescope will help us by giving us insights to some of the conditions that would be found very early on in the universe. Hubble and other similar land-based telescopes can't give us that insight because of not showing the infrared, the oldest informat
It is not exactly obstacles that cause the redshift, but rather the expansion of the universe. Dust can redden light, but this is really just subtracting blue light. Gravitational lensing is acromatic. In the gamma-rays, Compton scattering can shift photons to lower energy, but it does not preserve spectral features the way that the cosmological redshift does.
When they start getting images from the JWST, they'll see a dude in a flowing white robe and beard waving his arms; lip readers will ultimately be able to make out the words "Let there be light!" in Hebrew.
Why does this need a sunshield at all? The article says that the telescope should be parked in the 2nd Lagrangian point L2, which is 1.5 Gm from the Earth and should be permanently shaded from sunlight. Isn't the whole point of sending something to L2 that it is not exposed to the sun? Also, how is the energy supply supposed to work? Anyone out there who can shed some light on these questions?
Earth only has 12000km diameter. Sun has 1.4 million km diameter. For earth to give shade, it would have to be closer than AU*(r_earth/r_sun), which is much closer than the lagrange point. Simply put: you would get a dark spot on the sun, but no complete cover.
Something I've always wondered... how do the R&D costs compare to construction, testing, and launch of a satellite, or in this case, a space telescope? Wouldn't R&D be the hard part here, making the marginal cost of each additional spacecraft relatively small in comparison to the upfront cost?
It's my understanding that there's a substantial waiting list to use Hubble, and that a lot of very good research can't get done because telescope time is so limited. Time on JWST will probably be similarly limited... if we've spent $3.5B on this thing so far, why not put an extra $250M into it and get twice the benefit?
The last fancy telescope was named after an astrophysicist who made a significant contribution to our understanding of the universe, using the red shift to prove that the universe is indeed expanding, now commonly known as Hubble's law. The new telescope is named after an administrator. An important job, and done very well by the sounds of it, but it's not super-science. Am I the only one who sees the difference between running an agency and advancing the body of scientific knowledge? In 100 years time (heck, even today) who's name will we know?
It looks like James Webb was administor from 1961 to 1968, some very important years in spaceflight I'd say. The last moon walk was taken a year before I was born, so I don't have any direct experience with that era of space exploration. But I'm still amazed at how fast NASA moved from launching a satellite into orbit to putting men on the fricking moon and bringing them back safely. I wouldn't be surprised if this were in large part due to good leadership without which those accomplishments would have h
..."JWST is named after James E Webb, Nasa Administrator during the Apollo lunar exploration era; he served from 1961 to 1968."
To add more evidence. Look, wikipedia! http://en.wikipedia.org/wiki/James_Edwin_Webb [wikipedia.org]
To 1-up wikipedia. Look, NASA! http://www.jwst.nasa.gov/whois.html [nasa.gov]
The man whose name NASA has chosen to bestow upon the successor to the Hubble Space Telescope is most commonly linked to the Apollo moon program, not to science.
Yet, many believe that James E. Webb, who ran the fledgling space agency from February 1961 to October 1968, did more for science than perhaps any other government official and that it is only fitting that the Next Generation Space Telescope would be named after him.
Why are you spending money to have an internet connection, when you could give the money to people starving on this planet? Do you know what that money could buy for some poor people?
If the political will to feed the starving was here, we could do so and still put up the telescope. We spend the cost of the telescope a year on farm subsidies to prevent farmers from growing more crops. But the powers that be don't really give a shit.
Shuttle range wont really matter. They're retiring the fleet. I'm not sure if it will be in Ares I range or not, but it will surely be in Ares V range. The one thing I worry about on the whole Ares/Orin setup. The shuttle wasn't the best of designs for a lot of things, but one thing it was - it was a good work platform. Going back to capsules is great for a lot of reasons, but I do think an Ares V work platform module would be a good idea. Maybe even Ares I launchable fuel containers. I'll run that p
Big Bang was no explosion, it was the expansion of space. The shape of space is a question that's been open to some discussion, but you should not assume that the light got away and is sitting on the "edge" somewhere (or expanding the edge), because there is no such edge. Also, during much of the initial period of the universe's existence, it was opaque -- the energy levels of matter were high enough that just about any EM radiation was continuously absorbed and re-emitted, giving us the background radiation.
The most important aspect here might also be the fact that space expansion is a local event. On a large enough "distance", the speed of that event, if we just tried to add together the relative expansion per unit length, would exceed c. It can certainly approach it. There is/should be matter much farther away than the 2 * 15 bly "bubble" that would be the theoretical maximum of matter simply going in all directions at the point of Big Bang.
So if this one breaks ... (Score:5, Funny)
Re:So if this one breaks ... (Score:5, Informative)
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Re:I thought space telescopes were obsolete... (Score:5, Informative)
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Re:I thought space telescopes were obsolete... (Score:4, Interesting)
$5 Billion dollars DOES seem like a lot. But look at the U.S. Budget in the last decade. Look at the money we've essentially THROWN AWAY. By comparison, $5 billion for an advancement of science seems rather reasonable, or at the very least, reasonable by comparison.
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Re:So if this one breaks ... (Score:5, Funny)
They're far more likely to do something new - like tell it to go to the other side of the sun, via the centre of the sun.
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Re:So if this one breaks ... (Score:5, Funny)
That's ok, they can get it to land at night.
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Keeping Hubble (Score:5, Interesting)
An servicing the Hubble is judged to be so risky that NASA originally did not plan to do it. Now they intend to do it, but with a backup shuttle in orbit in case the first one gets into trouble.
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Re:Keeping Hubble (Score:5, Informative)
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Re:Keeping Hubble (Score:5, Informative)
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Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
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Re:Keeping Hubble (Score:5, Interesting)
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We dont need hubble for visible... (Score:2, Informative)
Dont forget that "hugely expensive" for a ground telescope is compareable to "dirt-cheap" for a space-based one.
All 4 of the VLT telescopes were (IIRC) cheaper than a single hubble service mission. And OWL should be compareable to a modern space-telescope, too, for a fraction of the price (dont forget: its a tradeoff: better seeing vs "have to design a mirrror that can withstand the acceleraion and f
Re:We dont need hubble for visible... (Score:5, Informative)
Your cost estimates are accurate, but the rest of your argument is total shit. Adaptive optics, WHEN it works (which is rarely, and with difficulty), can approach the angular resolution of HST in a VERY SMALL field of view. You cannot get 0.05 arcsec, diffraction limited images over a wide field of view, that is possible with HST.
"Designing a mirror to withstand a launch vehicle" is a problem that has been solved. And the only two current, viable telescope proposals for telescopes larger than 10m are the Thirty Metre Telescope (TMT [tmt.org]) and the Giant Magellan Telescope (GMT [gmto.org]). OWL is not a concept that is being taken very seriously...ESO certainly hasn't put its money where its mouth is.
Your final point, about not many lines in that part of the spectrum, belies a complete lack of understanding of what you are talking about. The UV (accessible with STIS, and the Cosmic Origins Spectrograph, which will fly on SM4 in late '08) are so full of lines that they overlap all over the place. See, for example, Morton (2003), ApJS, 149, 205, for a comprehensive list. At low redshift, lines of HI, OI, OVI, CIV, NV, CII, SiII, SII, FeII, NI...all are in the UV, in the STIS band. Furthermore, space is the ONLY place these wavelengths can be observed, because of the atmosphere is opaque to wavelengths shorter than about 3300 angstroms.
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Re:We dont need hubble for visible... (Score:5, Funny)
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My only thought was that if it is to replace Hubble it should be able to do everything Hubble can and then some.
Re:We dont need hubble for visible... (Score:4, Funny)
You must be new here.
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Re:Keeping Hubble (Score:5, Insightful)
That would be retarded; the most dangerous phases of the mission are launch and reentry, with a significantly lower risk of something going wrong while in orbit; something likely to either be so terrible you can't do anything or managable enough that you have a good long while to worry about it (e.g one of the tiles gets damaged at launch and you can't reenter safely, ala Columbia).
So no, it won't be in orbit, the backup shuttle will simply be ready to launch if needed.
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Re:Keeping Hubble (Score:5, Interesting)
Can you please site a source for this? Right now the software cannot actually support more than one shuttle in orbit at a time, if you look there has never been more than one up at a time. If there were this type of upgrade coming I could buy that story, but considering we're going to retire the fleet soon I don't see that as likely. I haven't installed any Aries specific equipment yet, but judging by the age of most of the shuttle specific equipment on the ground they're not going to do that level of a software rewrite for the shuttle when the fleets this close to retirement. Another issue with this statement is the shear altitude of the Hubble, well above ISS orbit. If we launched one into high orbit, and kept one at low orbit the one in low orbit simply wouldn't be able to reach the one in high orbit without landing for fuel anyways. Those things launch with their trajectories pretty much set and only do slight manuvering. STS-125 is the designated flight for Hubble servicing to be done by Atlantis, there is an as yet unnumbered contingency rescue flight, I don't think they number those unless they launch these days. They may put Discovery on the pad in ready position for rescue, but I seriously doubt they'll launch it unless they have to.
On another note:
There are emergency two shuttle protocols. What that comes down to more or less is equipment time sharing.
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Grou nd based solar power: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html [blogspot.com]
Re:Keeping Hubble (Score:5, Interesting)
Yes, the JWST is an infrared telescope. But, as another post further down alludes to incorrectly (for which they were smacked down and corrected by someone else) the James Webb is able to see further back into the history of the universe than we have ever been able to observe. What started out as visible light all those billions of years ago (and billions of light years away) becomes red-shifted into the infrared as the universe expands and, in a nearly literal fashion, stretches out that incoming light.
So while the Hubble has been responsible for a lot of great science, and truly breath-taking images, we have the potential to do so much more and better understand our universe with the JWST. We haven't maxed out the potential of the Hubble (probably never would), and I would love to keep it, but if there's only enough to deploy the JWST (and it's already been pushed back by several years), or keep on servicing the Hubble, my vote would be in favour of the JWST.
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Completely Offtopic!!!!! (Score:3, Funny)
Move on to the next subject!!!!
I have Karma to burn....mod's do not hold any fear for me!!!!
is it just me (Score:5, Funny)
Gaia (Score:5, Interesting)
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Let's hope they will agree on non-intersecating orbits for Gaia and JWST.
Gaia team: Hey! We were here first!
JWST team: "Here"? You are oscillating all around the place!
Gaia team: Ours is an elegant Lissajous orbit. What is yours?
JWST team: We'll pwn the L2 point itself!
Gaia team: No way! Our probe will intersect it in 13 days.
JWST team: Metric days or imperi
Oldest pictures of the universe (Score:2, Informative)
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Six years? (Score:4, Interesting)
Re:Six years? (Score:5, Funny)
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Let me guess.... (Score:3, Funny)
-Mike
sunshield? (Score:5, Interesting)
ignatius
Re:sunshield? (Score:5, Informative)
Earth only has 12000km diameter. Sun has 1.4 million km diameter.
For earth to give shade, it would have to be closer than AU*(r_earth/r_sun), which is much closer than the lagrange point.
Simply put: you would get a dark spot on the sun, but no complete cover.
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Why not build two? (Score:5, Insightful)
It's my understanding that there's a substantial waiting list to use Hubble, and that a lot of very good research can't get done because telescope time is so limited. Time on JWST will probably be similarly limited... if we've spent $3.5B on this thing so far, why not put an extra $250M into it and get twice the benefit?
Any experts care to weigh in?
By the way,... (Score:3, Interesting)
from French Guyana.
http://www.uibk.ac.at/ipoint/news/images/esa_pic_
What's in a name? (Score:3, Insightful)
http://en.wikipedia.org/wiki/Edwin_Hubble [wikipedia.org]
http://en.wikipedia.org/wiki/James_Edwin_Webb [wikipedia.org]
Name a scientist (Score:3, Insightful)
It looks like James Webb was administor from 1961 to 1968, some very important years in spaceflight I'd say. The last moon walk was taken a year before I was born, so I don't have any direct experience with that era of space exploration. But I'm still amazed at how fast NASA moved from launching a satellite into orbit to putting men on the fricking moon and bringing them back safely. I wouldn't be surprised if this were in large part due to good leadership without which those accomplishments would have h
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Re:color me not impressed (Score:5, Informative)
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To quote the article...and wikipedia...and NASA... (Score:5, Informative)
To add more evidence. Look, wikipedia!
http://en.wikipedia.org/wiki/James_Edwin_Webb [wikipedia.org]
To 1-up wikipedia. Look, NASA!
http://www.jwst.nasa.gov/whois.html [nasa.gov]
The man whose name NASA has chosen to bestow upon the successor to the Hubble Space Telescope is most commonly linked to the Apollo moon program, not to science. Yet, many believe that James E. Webb, who ran the fledgling space agency from February 1961 to October 1968, did more for science than perhaps any other government official and that it is only fitting that the Next Generation Space Telescope would be named after him.
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Re:Haha (Score:5, Insightful)
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Re:The light's long gone! (Score:5, Interesting)
The most important aspect here might also be the fact that space expansion is a local event. On a large enough "distance", the speed of that event, if we just tried to add together the relative expansion per unit length, would exceed c. It can certainly approach it. There is/should be matter much farther away than the 2 * 15 bly "bubble" that would be the theoretical maximum of matter simply going in all directions at the point of Big Bang.
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