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How To Build a Telescope That Trumps Hubble

samzenpus posted more than 3 years ago | from the bigger-and-badder dept.

NASA 185

An anonymous reader writes "In cleanrooms around the country NASA and its contractors are building the James Webb Space Telescope, a marvel of engineering scheduled to launch in 2014. This gallery shows the features that will allow Webb to take the universe's baby pictures in infrared — most notably an 18-segment mirror and a 5-layer sunshield. I can't wait until Webb settles into its Lagrangian point way out beyond the moon and gets to work."

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strange brew that's also good for you (0)

Anonymous Coward | more than 3 years ago | (#35224884)

That would be home made Kombucha(org). It's alive.

The universe is infinite (2, Interesting)

ubergeek65536 (862868) | more than 3 years ago | (#35224896)

So why do they thing that the universe isn't infinite? It seems that every time they get a bigger telescope the size of the universe gets bigger :\ Did they ever think that that big bang thing could have just been a localized event?

Re:The universe is infinite (1)

Ancantus (1926920) | more than 3 years ago | (#35224936)

Because nothing that we have observed so far is infinite, so its very hard to come to the conclusion that something is infinite without a base reference of what infinity really is.

Re:The universe is infinite (1)

ubergeek65536 (862868) | more than 3 years ago | (#35224990)

Tell that to the high school teacher that insists that they have proof because most articles and papers don't make the distinction between the the word universe and the term observable universe. Many astrophysicists don't even know the difference. Assumptions are not what science should be based on.

Re:The universe is infinite (1)

timbo234 (833667) | more than 3 years ago | (#35225418)

For experimental/observational science 'the universe' and 'the observable universe' are the same thing, as by definition that's all we can know actually exists. If you think there's a distinction between the 2 terms you're the one making an assumption.*

* This is not necessarily a bad thing, there are many cosmological theories that feature the idea that there are vast areas of the universe beyond our current abilities to detect them. However all such theories are only at the hypothesis stage - currently without observational or experimental evidence.

Re:The universe is infinite (1)

WaffleMonster (969671) | more than 3 years ago | (#35225598)

For experimental/observational science 'the universe' and 'the observable universe' are the same thing, as by definition that's all we can know actually exists. If you think there's a distinction between the 2 terms you're the one making an assumption.*

This is incorrect. The observable universe is different at every point in the universe. A distant object under our observation may be influenced by events outside of our light cone which we can only indirectly observe.

Re:The universe is infinite (1)

melikamp (631205) | more than 3 years ago | (#35225066)

If you regard infinity as a negative concept, you can also say that a thing is infinite as long as it's not known to be finite. The universe is infinite in this sense. One can even try to argue that everything material is, strictly speaking, infinite, and finiteness can only be verified for mental constructs such as mathematical objects. Considering that we do not know what exactly an electron is, it is at least possible that there are vast expanses of space-time folded there, extending forever into some exotic singularity.

Re:The universe is infinite (1)

Gilmoure (18428) | more than 3 years ago | (#35225670)

Negative infinity makes my head hurt.

Re:The universe is infinite (1)

Froggels (1724218) | more than 3 years ago | (#35226086)

I've often wondered this my self. Every time scientist build a bigger telescope it means that the universe has to somehow just be bigger than they thought. Simply because they cannot build a telescope that cannot peer infinitely far into the universe doesn't mean that the universe might not be infinite or closed. It kind of reminds me of how up to only a few years ago scientist actually wasted the energy to actually debate the existence of exoplanets simply because none had yet ever been observed.

Re:The universe is infinite (5, Informative)

dkleinsc (563838) | more than 3 years ago | (#35225016)

Why do you think it is infinite, without any proof whatsoever? All evidence we have is that the observable universe is finite, and observations of the early universe (thanks to the finite speed of light) match what the Big Bang Theory predicted. Ergo, it's the best answer we've got right now, and the burden of proof is on those who have evidence to the contrary to produce it.

Is it possible there's an unobservable universe outside of the observable universe? Of course. But you can't do science with it because it is simply impossible to observe.

Re:The universe is infinite (2, Insightful)

ubergeek65536 (862868) | more than 3 years ago | (#35225074)

I have just as much proof that the universe is infinite as they do that it's not. That is to say exactly none. We will never be able to prove that it is infinite by measurement just and we will never be able to prove that it is finite. Like I said a hunch isn't exactly proof with either argument. A year ago the "universe" was about ten times smaller than it is now. Once the new telescope is functional I'm going to make the wild speculation that to will get bigger yet.

Re:The universe is infinite (2)

bunratty (545641) | more than 3 years ago | (#35225480)

I don't understand this idea you have that the amount of the universe we can observe is getting bigger. Since the 1960s, we've observed the cosmic background radiation. It's the thing farthest away we can observe, because before the cosmic background radiation became visible the universe was opaque. We have been able to resolve galaxies that are farther and farther away, but we knew that there was universe there. We just weren't able to see physical, gravitationally bound objects there before.

Re:The universe is infinite (1)

ubergeek65536 (862868) | more than 3 years ago | (#35225832)

The background radiation is just noise and we will never be able to measure it with enough precision to make the conclusion that we see all of the radiation out there.
We have no way to know how far away that source of radiation is.

Re:The universe is infinite (3, Informative)

Nemyst (1383049) | more than 3 years ago | (#35225910)

You really don't know much do you? The radiation comes from the beginning of the universe, back when everything was a huge soup of particles. It's one of the greater proofs for the big bang theory, since there's no other reason for it to be there than to have one point where the universe was so dense it was irradiating in a nearly uniform manner. By studying the irregularities in the emissions, we can then learn more about that state in the universe's evolution, as well as what happened after that.

There's no distance to speak of because when those were around, they were everywhere and the universe wasn't of the same dimensions. We can measure that the universe is expanding, the big bang theory says there was a time where it was essentially a singularity, thus we can say (with good probability of being right) that the universe is finite.

Is it finite in the sense of a sheet of paper? Probably not. There won't be a wall with "the Universe ends here." written on it. Rather, it might very well be like the flat Earth theories: a loop that uses an additional dimension to complete. Whereas the Earth is a 3D object that was being represented as 2D (so you'd have edges even though they do not actually exist), it's very possible the universe loops around in another higher dimension.

Re:The universe is infinite (2)

bunratty (545641) | more than 3 years ago | (#35226044)

You sound like Bill O'Reilly. Cosmic background radiation. You can't explain that.

Your argument is just like the arguments of people who disagree with evolution or AGW. You're just making stuff up to be argumentative. If you actually want to learn something, you can read about it [wikipedia.org] .

Re:The universe is infinite (0)

Anonymous Coward | more than 3 years ago | (#35225656)

If you can't observe it then there is no difference between it existing and it not existing.
Evidence doesn't even come into the equation.

Re:The universe is infinite (1)

hedwards (940851) | more than 3 years ago | (#35225194)

Actually, you're confounding the problem. The observable universe is always going to be finite until such a time as the observable universe and the universe are the same and the universe itself proves to have some sort of a limit in dimension.

I don't personally like the idea of confusing mass and energy with the dimension of the universe as you don't measure mass or energy with meters. If you're able to do that without any other units of measure, then you might have a point, but as it is there isn't any good reason to believe the things are related in that fashion.

Re:The universe is infinite (1)

ubergeek65536 (862868) | more than 3 years ago | (#35225326)

Actually, you're confounding the problem. The observable universe is always going to be finite until such a time as the observable universe and the universe are the same and the universe itself proves to have some sort of a limit in dimension.

That makes absolutely no sense. The universe is what it is regardless of what we think it is or whether or not we observe it.

Re:The universe is infinite (1)

Gilmoure (18428) | more than 3 years ago | (#35225682)

Maybe he's bounded in a nut shell?

Re:The universe is infinite (1)

Nemyst (1383049) | more than 3 years ago | (#35225988)

The observable universe doesn't "exist". It's just a construct, an abstraction we've created to describe what we, here on Earth, can see. It's not material. you could say it's just like a country's frontiers, something that matters for us humans but that doesn't really exist otherwise. The observable universe is finite because of the speed of light and the age of the universe. We cannot see what light cannot bring to us. With time, the observable universe will expand, since light from farther away will be able to reach us. However, the expansion of the universe might stop that light from reaching us, since we know it can be extremely fast for distant objects.

Also, we don't care about the rest of the universe. Only the observable universe matters, at least until we manage to get off this rock and change/expand the observable universe.

Re:The universe is infinite (1)

msauve (701917) | more than 3 years ago | (#35225204)

Why do you think it is infinite, without any proof whatsoever?

It all boils down to definition. What is the size of the universe? Is it the extent of space which contains matter? light? That is finite, according to our current knowledge, but is usually called "the observable universe." Is there something which prevents it from growing infinitely (aside from gravity and the potential "big crash")? Observations show the observable universe is still expanding, and there is legitimate argument that growth can continue forever (the "big freeze"). Doesn't that imply an infinite universe (beyond what is observable)?

What sort of "proof" would you demand?

Re:The universe is infinite (1)

Nemyst (1383049) | more than 3 years ago | (#35226012)

You can count to infinity (though it would take an infinite amount of time). That doesn't mean you are infinite or the number you are counting is. In the same manner, the universe can be expanding forever without ever being infinite.

Re:The universe is infinite (0)

Anonymous Coward | more than 3 years ago | (#35226284)

It's simpler than that. They're inferring, "All evidence we have is that the observable universe is finite," because they're looking through curved space-time. They're looking at an image indicative of matter generated by recording light that traveled through dynamic-space time and assuming they understand enough about that space-time path to ensure that what they see is accurate. Yeah, I don't buy it.

Here's another example of how what you don't know leads to errors of assumption. You have light traveling in a straight path in an empty(ish) universe between two stars. You infer the relative speed they travel apart based on observed frequencies of light (red shift). However, there is also shift due to dust/matter in the path that causes dispersion and there is absolutely no way for you to know exactly how much dust there was as the light traversed the path.

Astronomers take amazing images of objects in space. I just wish they'd take it easy with the guesswork about distance/size when it comes to light that traveled for 14 billion years.

Re:The universe is infinite (0)

Anonymous Coward | more than 3 years ago | (#35226338)

You can count to infinity (though it would take an infinite amount of time). That doesn't mean you are infinite or the number you are counting is. In the same manner, the universe can be expanding forever without ever being infinite.

Lay off the weed for a day or so.

The point he is making, without trying to split hairs over the definition of "infinite" is that there is (apparently) no limit to the possible spatial extent of the universe, while there is (apparently) a fixed quantity of matter and energy that occupies the universe.

Re:The universe is infinite (1)

HotBits (1390689) | more than 3 years ago | (#35225284)

There is evidence that the universe is much larger than the observable universe (at least 250x), and is arguably infinite. Just because you can't see or measure it directly, doesn't mean you can't measure it indirectly: http://news.slashdot.org/story/11/02/01/2015250/Universe-250-Times-Bigger-Than-What-Is-Observable [slashdot.org] , http://www.technologyreview.com/blog/arxiv/26333/ [technologyreview.com]

Re:The universe is infinite (0)

Anonymous Coward | more than 3 years ago | (#35225658)

Is it possible there's an unobservable universe outside of the observable universe? Of course. But you can't do science with it because it is simply impossible to observe.

I know there's one, that's where the invisible dragon in my garage came from. ;)

Re:The universe is infinite (0)

Anonymous Coward | more than 3 years ago | (#35225024)

Because they think the universe is a 3-sphere, and therefore finite? Stands to reason, earth used to be flat and now it's round. Working with our current assumption that the universe started from a single point and grew outward really really fast at a moderately uniform rate, it's pretty much a sphere (big conjecture here on my part.) Step up from flat is spherical, step up from spherical is a 3-sphere. QED via history and human nature.

Re:The universe is infinite (1)

hedwards (940851) | more than 3 years ago | (#35225212)

It's only a sphere if it's finite in size, which is the problem. If you're defining the universe to be spherical then you're defining it to be finite in size. Which is largely fine at this point as we can't observe the furthest reaches that current theory predicts, but if we ever can see beyond it then we'll have to start really worrying about things like that.

Re:The universe is infinite (1)

Nemyst (1383049) | more than 3 years ago | (#35226034)

He's defining it to be hyperspherical. Not the same thing at all. The hypersphere, or 3-sphere, is the mathematical step up of a sphere from 3D space into 4D space. It's to a sphere what a sphere is to a circle.

A hypersphere would seem infinite by our measurements, despite being finite if you move into a higher dimension.

Re:The universe is infinite (4, Insightful)

fishbowl (7759) | more than 3 years ago | (#35225080)

Was space created by the Big Bang, or did the Big Bang happen inside of space that already existed?

Observe something that is more distant in space-time than the big bang, and settle the matter!

It is fine to speculate, but if you want coherent scientific models of the universe, you need to either assume the 13.7 billion light-year horizon or else show by observation or by theory that the horizon does not exist.

The ideas of an infinite theoretical universe aren't incompatible with a finite observable universe, but people who build telescopes are going to be concerned exclusively with the practical aspects of the latter, even if they believe in the former.

Re:The universe is infinite (1)

hedwards (940851) | more than 3 years ago | (#35225234)

Precisely, it's pretty well established that we can't view all of the universe. Given the speed of light and that we're using light or various waves that travel at or near the speed of light, I think it's pretty inescapable that we aren't seeing everything. For all we know just outside our range of observation is a giant window in some sort of even larger department store display case. Sure it's incredibly unlikely, but beyond the range of what we can sense all sorts of weird things could be happening.

Re:The universe is infinite (1)

pclminion (145572) | more than 3 years ago | (#35226646)

Was space created by the Big Bang, or did the Big Bang happen inside of space that already existed?

You ask it like it's some kind of unanswered question. Yes, space and time were created at the moment of the Big Bang. The question is HOW that happened.

Re:The universe is infinite (2)

Zorpheus (857617) | more than 3 years ago | (#35225090)

We can not see further than 13.75 billion light years because this is the distance that the light has travelled since the universe has become transparent. This happened 300,000 years after the big bang.
It does not really matter if it is infinite or not.

Re:The universe is infinite (1)

WaffleMonster (969671) | more than 3 years ago | (#35225462)

We can not see further than 13.75 billion light years because this is the distance that the light has travelled since the universe has become transparent. This happened 300,000 years after the big bang.

The distance light has really traveled is much much more than the speed of light as it is also dependant on hubble expansion..depending on your POV.. at some point in time and distance you reach a point where you can not see further regardless of the universes age because the portion of the universe under observation expands faster than the direct propogation of information. The universe (in terms of energy from the big bang) is currently hundreds of times larger than our directly observable universe.

Re:The universe is infinite (1)

bobs666 (146801) | more than 3 years ago | (#35225214)

IMHO, Astronomers forget to use the word visible, when they say universe. Given the Universe is expanding stuff we can see is exiting the Visible Universe all the time. So the result is the Visible Universe is shrinking. And one day there will be noting to see when you look up into the night sky. So I an told on Astronomy.fm

So if there another big bang overlapped our Visible Universe we might see a big corner of space blue shift. You can bet a lot of papers would get written about that.

To defend Astronomers You could say a big Goat head butted a fence and that kicked off the Big bag. Who could prove you wrong. Astronomers can't Observe that, so its speculation and an Astronomer will simply say We do not know What caused the big bang. We do not know if there was another big bang we can only see one. We only know about what we can Observe.

So you can speculate all you want. But until you can Observe another Big bang, the answer is no one knows.



PS.

Some people want a visible light telescope to replace Hubble. But think about it, Given you want to look far away, and that the farther away you look the faster things are moving away and thus are red shifted, so what was visible light is shifted in the infrared.

Got that? looking at infrared light far away is actually looking at what was visible light.

Re:The universe is infinite (1)

peragrin (659227) | more than 3 years ago | (#35225792)

I actually want both. The hubble is awesome because it has multiple camera's and can view objects in multiple wave lengths.

Infrared is good, ultraviolet is good, but you can't get some of the stunning images the Hubble has produced without some visible wavelengths as well.

What was that comet? Levy 9 that hit jupiter years ago?? only the hubble got good images off of that. James webb won't be able to do such things. So we need both or even better, both in a binocular fashion. So we can see the same image from the same spot in multiple wave lengths to really get a good idea of it.

Re:The universe is infinite (1)

TapeCutter (624760) | more than 3 years ago | (#35225946)

IMHO, Astronomers forget to use the word visible, when they say universe.

I don't think they forget, I think they know it's redundant since traditionally "the Universe" (uppercase 'U') is everything, and "the universe" (lowercase 'u') is the visible universe.

Re:The universe is infinite (1)

natehoy (1608657) | more than 3 years ago | (#35225228)

So why do people still think that a telescope magically expands the size of the actual Universe and ignore the important term "Known" or "Observed" that any decent astronomer uses when describing what they can see and observe?

Universe != Known Universe.

The definition of the size of the Universe is a matter of philosophy, religion, theory, or whatever term you want to use to describe "make shit up that we'll probably never be able to prove or disprove, so we can all safely argue about it from positions of held assumption".

The definition of the size of the Known Universe is a matter of observation, mathematics, and some margin-of-error guesswork because we don't have a yardstick of sufficient length. Every time our instruments get more powerful, we see further off, and the size of the Known Universe expands. The Known Universe will not, in any finite span of time with finite method of observation, be infinite. Meanwhile, the actual Universe may well be infinite, even possibly in ways we can't imagine (parallel universes, dimensions, etc). Or it may be finite, in which case it introduces a simple question - what is it bordered by, what's outside that border, and why isn't whatever is outside that border considered part of the Universe (you see, I struggle with the concept of infinity, but I struggle with the concept of the Universe being finite even more, but I'm just a dumbass programmer).

Re:The universe is infinite (1)

melikamp (631205) | more than 3 years ago | (#35225296)

Did they ever think that that big bang thing could have just been a localized event?

I am willing to bet money that they do (I am assuming you mean professional physicists). This guy [wikipedia.org] , for example, thinks that bangs may be happening inside black holes, and new universes are created all the time, with parameters "inherited" from parent universes. This is almost an evolutionary interpretation of the largest-scale cosmology, with the parameters of our own universe being this way because other sets of parameters caused premature death (say, a big freeze) before new universes could be created. This is all great and I for one totally buy it up, but physics is already entirely too complicated, and no one wants to work with more complicated models when the simplest model agreeing with the experimental evidence is the incredibly-convoluted Lambda-CDM. So of course the Universe could be infinite or finite, flat or curved, expanding here and contracting elsewhere, or something we don't even have words for right now. To make a splash in physics, it's not enough to come up with an idea: you also need to exhibit a smoking gun.

Not statically infinite (0)

Anonymous Coward | more than 3 years ago | (#35225352)

The Universe used to be thought of as statically infinite until someone realized the implications:

1) If Universe is static, the universe must be (generally) uniform, otherwise a large clump of mass will gather all nearby mass to itself (thus invalidating static assumption).
2) If the Universe is static, it is, has been and always will be as it is now, thus it is infinitely old.
3) If Universe is infinite (and generally uniform), there are stars in every direction.
4) If there are stars in every direction, and the universe is static (ie. infinitely old), the night sky should be white (with star-light) not black.
4a) Starlight cannot have been blocked either, as anything blocking the light would be absorbing it for an infinitely long time, and thus would be heated to the temperature of the sun and thus emit light as well.
4b) Since earth is also not as hot as the sun, the theory is twice debunked.

So, at least the static infinite universe theory is debunked.

Re:The universe is infinite (1)

Chris Burke (6130) | more than 3 years ago | (#35226050)

So why do they thing that the universe isn't infinite?

Do you mean infinite in size, or infinite in age? Because the only implication of the summary or article is that the universe is finite in age. And there are pretty good theories with lots of observational support that suggest that the universe-as-we-know-it has a finite age.

It seems that every time they get a bigger telescope the size of the universe gets bigger :\

No, actually, that's not the case at all. Bigger telescopes have allowed us to see to points asymptotically approaching the theorized age of the universe, but it's been a long time since a bigger telescope has actually meant we had to revise our estimates of the age and size of the universe towards older.

So, you're base observation is off-base.

Did they ever think that that big bang thing could have just been a localized event?

Of course, also that it's just one Bang of a sequence that's been happening over and over, and other possibilities. However your specific case, that it's something "local" in a space-time sense, doesn't match the observations as well as theories in which it is that space-time itself erupted from the Big Bang, everywhere was "local" to the Big Bang, and it's only as space itself expanded that we can think of parts of the universe as not being local.

How To Build a Telescope That Trumps Hubble (3, Funny)

Anonymous Coward | more than 3 years ago | (#35224918)

Put a bad toupee on a telescope.

Budget Cuts and the JWT (3, Informative)

Petersko (564140) | more than 3 years ago | (#35224952)

The budget cuts announced by Obama include cutting $64 million from the James Webb Telescope program, "which an indendent group of experts "found to have a fundamentally broken estimate of cost and schedule". [cnn.com]

While I recognize the U.S. is totally fucked, economically, this is a mistake. Throwing a minor budget item with huge potential like this under the bus in the name of pretending to become fiscally responsible is beyond short-sighted.

Re:Budget Cuts and the JWT (3, Interesting)

DisownedSky (905171) | more than 3 years ago | (#35225110)

A 64 million dollar cut isn't much at JWST's burn rate. It's not being thrown under the bus at all. In fact, it's eaten all the money intended for other, equally worthy space science mission. Realistically, it isn't going to launch until 2015 at the earliest (my money's on 2016) and will cost much more than it's current massive overrun.

You're Right (0)

Petersko (564140) | more than 3 years ago | (#35225200)

I wasn't aware the JWST was impacting other programs. The impression I got was mistaken - that this cut was really significant.

Even so, will this funding reduction accomplish anything other than to push back the schedule?

I don't know why they're worrying anyway. They can just print the money. So far that's working

Re:You're Right (0)

Anonymous Coward | more than 3 years ago | (#35225746)

That thing was supposed to have flown 4 years ago...

Re:Budget Cuts and the JWT (2, Funny)

dkleinsc (563838) | more than 3 years ago | (#35225156)

While I recognize the U.S. is totally fucked, economically, this is a mistake. Throwing a minor budget item with huge potential like this under the bus in the name of pretending to become fiscally responsible is beyond short-sighted.

The reason that's happened is that the US is totally fucked politically as well as economically.

Re:Budget Cuts and the JWT (1)

Big Smirk (692056) | more than 3 years ago | (#35225262)

No problem. They'll just save that money by skipping a few focal length tests on the mirror.... Oh wait...

Re:Budget Cuts and the JWT (1)

hedwards (940851) | more than 3 years ago | (#35225288)

That's what we call being "fiscally conservative." You sign off on massive debt for wars and other pointless silliness even as you cut funding to tiny projects that are likely to lead to prosperity in the future. To put it into perspective, anything that costs less than about $15b isn't worth obsessing a lot over. That's about $1 a week per person for the year, sure it adds up but we're not going broke on that. We're going broke on big budget items like the overspending on the DoD and welfare for billionaires.

Re:Budget Cuts and the JWT (0)

Anonymous Coward | more than 3 years ago | (#35225364)

We're going broke on big budget items like the overspending on the DoD and welfare for billions

FTFY

Re:Budget Cuts and the JWT (1)

CrimsonAvenger (580665) | more than 3 years ago | (#35225646)

You sign off on massive debt for wars and other pointless silliness even as you cut funding to tiny projects that are likely to lead to prosperity in the future.

I'm really curious as to how the JWT is expected to "lead to prosperity in the future". Off the top of my head, I can't foresee anything meaningful to our standard of living coming from IR pictures of the early universe.

Re:Budget Cuts and the JWT (1)

natehoy (1608657) | more than 3 years ago | (#35225530)

You could say the same thing about most of the cut items, but the problem is that we can't touch the Holy Trinity (military, tax breaks, and the entitlement programs). The Trinity accounts for too large an amount of the budget for anything else to mean fuck-all to the deficit. Even if you cut pretty much everything but the Trinity, we'd still have a deficit.

Raise taxes across the board, you're a right-wing baby-killer. Raise taxes on the rich, you're a job-killing pinko communist. Cut the military, you're a terrorist-loving peacenik asshole. Assess taxes on Churches, you'll be excommunicated from your cult before you get recalled. etc etc.

Re:Budget Cuts and the JWT (1)

Lord Ender (156273) | more than 3 years ago | (#35225948)

While I recognize the U.S. is totally fucked, economically

The Federal government is kinda fucked fiscally (though not irrecoverably so), but the U.S. itself is pretty well-off economically. Our unemployment rate is "only" 9% and we have one of the highest median household incomes in the world. Parts of Asia may have lower unemployment at present, but you really need to have everyone working when you make $2000/year on a full-time income.

eliminate the manned space program (0)

Anonymous Coward | more than 3 years ago | (#35226114)

How much scientific data has the manned space program, which costs several billion a year, generated in the last several years compare to the data the James Webb telescope will generate? Please cut the expensive meatbags before going after our reliable robots.

Re:Budget Cuts and the JWT (1)

Kiliani (816330) | more than 3 years ago | (#35226590)

If I remember correctly, six months ago it was to cost 5 billion dollars ($5,000,000,000) for a 2014 launch date. If the launch slips (and believe me, it will), you can add a couple of $100M (that's several $100,000,000) before all is said and done. Just look at the Mars Science Laboratory rover to learn how it is done. $64M is peanuts when it comes to that.

Teaser title! (0)

Anonymous Coward | more than 3 years ago | (#35224964)

It gave me the impression I could build something like that in my garage.

How about: "How Scientists are Building a Telescope That Trumps Hubble!"

Re:Teaser title! (2)

natehoy (1608657) | more than 3 years ago | (#35225600)

Meaning no offense, but have you ever actually submitted a story? Titles are limited to 50 characters. It leads to terrible, terrible headlines.

"How Scientists are Building a Telescope That Trumps Hubble!" gets truncated to "How Scientists are Building a Telescope That Trump"

Many of the bad headlines here are actually the result of trying to get something like "How scientists are building a telescope that is superior to Hubble" in a headline field that basically only allows "Science cool! They build'um Hubbleplus Telescope!" (note that, coincidentally, my headline just happens to fit with ZERO extra spaces.)

I hope they're building several of these (2)

PeterM from Berkeley (15510) | more than 3 years ago | (#35224994)

I think just having "one" Hubble space telescope was a mistake. I hope they're building more than one of these new 'scopes.

I mean, it'd be a shame if a launch incident destroyed a unique capability. And it shouldn't cost anything like N times as much to build N of these at the same time, right?

--PM

Re:I hope they're building several of these (4, Informative)

Anonymous Coward | more than 3 years ago | (#35225058)

Of course not - the thing is a few billion Dollars to build and not exactly cheap to launch either.

In fact - if it does break, even if just in a minor way (e.g. the solar panels don't unfold because a space flea is jamming a gear), it's likely going to be a multi-billion dollar piece of space junk.
Why? Because it's going to sit at the Lagrange 2 point when it goes operational. That's far, far further than we've put humans (way beyond the Moon), which so far have been the only instruments adapt enough to do repairs on satellites (such as the ones for Hubble).

As it is, the James Webb Space Telescope is awesome - in infrared and -only- infrared. People suggesting it's a -replacement- for Hubble (IR, Visible, UV) are completely and utterly deluded.. or looking for additional grant money. They might as well claim it's a replacement for Chandra (X-Ray) as it's almost equally as idiotic.

Re:I hope they're building several of these (0)

Anonymous Coward | more than 3 years ago | (#35225810)

As it is, the James Webb Space Telescope is awesome - in infrared and -only- infrared. People suggesting it's a -replacement- for Hubble (IR, Visible, UV) are completely and utterly deluded.. or looking for additional grant money. They might as well claim it's a replacement for Chandra (X-Ray) as it's almost equally as idiotic.

Well then you are "idiotically" wrong. The 600nm filters in NIRCam must be there just for the lulz!

The JWST does indeed work down into the visible. In fact, until fairly recently in JWST program history there was even a spec for diffraction limited performance at the far visible wavelengths! (it was lifted a few years back to save a truckload of cash on manufacturing costs, but the observatory will still routinely be used down in the visible!)

Re:I hope they're building several of these (4, Informative)

spacemandave (1231398) | more than 3 years ago | (#35225324)

Actually, more than a dozen "Hubble space telescopes" were built and launched into orbit. The biggest differences are that they point at the Earth instead of away from it, and they are called KH-11 instead of HST. Oh, and their imagery data is mostly classified.

Re:I hope they're building several of these (1)

judoguy (534886) | more than 3 years ago | (#35225674)

Citation please. Not that I don't believe it, just would like more info.

Re:I hope they're building several of these (0)

Anonymous Coward | more than 3 years ago | (#35225970)

Oh, yeah, zing, good one.

Re:I hope they're building several of these (1)

DerekLyons (302214) | more than 3 years ago | (#35226356)

it shouldn't cost anything like N times as much to build N of these at the same time, right?

It depends on how you calculate N.
 
If you look at the total cost of the satellite (cost to procure the bird + the birds amortized share of the R&D program), then yes - N drops considerably. But that's not really an accurate method of accounting in this instance because you're performing the R&D no matter how many you build.
 
If you define N as the opportunity cost (just the direct costs to procure the bird), then maybe - N does drop, but not as much as you might think.
 
The reason it doesn't drop as much as you might think is the massive amount of man hours devoted to testing, verification, and QA of each component.

Baby pictures? Infrared? Awesome! (1)

acidradio (659704) | more than 3 years ago | (#35224998)

I wonder what would happen if we started taking baby pictures in infrared. Maybe NASA just thought of something that every Sears Portrait Studio should offer.

1. Take baby photos in infrared
2. See stars and other galaxies
3. PROFIT!

I'd rather build a proctoscope that humbles Trump. (0)

dameron (307970) | more than 3 years ago | (#35225002)

nt

Ares and Constellation (1)

TopSpin (753) | more than 3 years ago | (#35225012)

JWST is great and I'm glad their building it. Prior to canceling Constellation, NASA was investigating this:
http://www.youtube.com/watch?v=2YsNvpVSzbI [youtube.com]

It wasn't all about space cowboys. In terms of cosmology, if this had been only thing Ares V had ever accomplished it would have been worth every cent.

Maybe China will get there.

Look at the price tag (3, Interesting)

PineGreen (446635) | more than 3 years ago | (#35225018)

As a professional astronomer I hoped this thing would never have happened. It costs 6 billion and at this price tag a 5% overrun is $300 million, about six times the cost of the entire SDSS project, which has undoubtedly gave us more science that James Webb ever will. True, Hubble and JWST make great pictures, function as amazing PR machines, but most science at the end of the day comes from survey imaging and spectroscopic observations.

Re:Look at the price tag (3, Insightful)

JoeMerchant (803320) | more than 3 years ago | (#35225180)

SDSS was good science, making great use of relatively humble tools. But, it takes an ecosystem - and heavyweight instruments like the Webb, or the LHC, will illuminate things that can later be confirmed with the broader toolset of more pedestrian instruments, things that would just be considered a wild theory unless they came with backing from observations on an instrument like the Webb.

You also need to face up to the reality that if the Webb were scrapped at inception, it wouldn't have meant $6B extra would have been supplied to general astronomy, only a small fraction of that money would have made its way around the community.

Re:Look at the price tag (2)

melikamp (631205) | more than 3 years ago | (#35225726)

I totally believe you when you say that surveys provide more and better scientific data, but as a tax-payer I am thrilled with HST's performance, and I could hardly be happier about this wealth of data [hubblesite.org] , which is useful to everyone, professionals and amateurs alike. The only thing I dislike about JWST is that we cannot service it, as so we miss an opportunity to launch more people into space. You guys could turn the surveys into PR machines too, you know. In KStars, for example, there are shortcuts to download DSS and SDSS. I click on the star map and a DSS picture for that place gets pulled. But it could be so much better: DSS is slow to the point of being unusable, and the available SDSS data doesn't seem capture that much of the sky. With a bit of tweaking, I bet we could have a google-map-like app for the surveys to blow everyone's mind, and then you'll see more cash pouring in for these kinds of projects.

DOUBLE ORIGINAL PRICE (1)

peter303 (12292) | more than 3 years ago | (#35225924)

$6.5B versus $3.5B. Much of that cost overrun is from being years late.

Re:DOUBLE ORIGINAL PRICE (0)

Anonymous Coward | more than 3 years ago | (#35226388)

"First rule of government spending. Why build one when you can have two at twice the price?"

Re:Look at the price tag (4, Insightful)

DerekLyons (302214) | more than 3 years ago | (#35226664)

As a professional astronomer I hoped this thing would never have happened. It costs 6 billion and at this price tag a 5% overrun is $300 million, about six times the cost of the entire SDSS project, which has undoubtedly gave us more science that James Webb ever will.

Science isn't something you can measure by how many buckets you collect. Not all buckets have the same value.
 

True, Hubble and JWST make great pictures, function as amazing PR machines, but most science at the end of the day comes from survey imaging and spectroscopic observations.

If you honestly believe that all Hubble and JWST are doing or will do is collect pretty pictures, you're either hopelessly ignorant or hopelessly biased. But ff you want to talk spectroscopy - consider that four of the Hubble five main instruments are dedicated to spectroscopy, and two of JWST's three main instruments are so dedicated. If you want to talk surveys... Check out Hubble's schedule from Feb 14, 2011 [stsci.edu] , or January 29, 2011 [stsci.edu] for some recent survey campaigns that Hubble is participating in.

There is no "do over" for James Webb (4, Informative)

Just_Say_Duhhh (1318603) | more than 3 years ago | (#35225044)

Not that I'm expecting some catastrophic screw-up on the scale of the Hubble, but if there is a problem with the JWST, once it is sitting out at the Earth-sun L2, we won't be able to go visit it and repair it. I haven't heard of any contingency to allow it to come back to earth, so they've really got one shot to get it right.

I'm hoping everything is nominal.

I was thinking the same. (1)

Picass0 (147474) | more than 3 years ago | (#35225266)

Hubble didn't work out of the box. From the moment it was deployed there was a spacewalk to unfold one of it's solar panels. Then there was a famous 'set of glasses' fix to it's optics. There have been hardware upgrades and gyroscope fixes.

It takes only one small glitch for this to be an expensive piece of space junk. It would kill any future space telescope in the process.

Re:I was thinking the same. (1)

Grizzley9 (1407005) | more than 3 years ago | (#35225604)

Surely there's a progressive plan in place to test it out in low earth orbit before launching to L2? Make sure it works before sending it beyond our reach. Seems a bit of extra time and effort on that part would be good insurance on a $6B project.

Re:I was thinking the same. (1)

WaffleMonster (969671) | more than 3 years ago | (#35225782)

Hubble didn't work out of the box. From the moment it was deployed there was a spacewalk to unfold one of it's solar panels. Then there was a famous 'set of glasses' fix to it's optics. There have been hardware upgrades and gyroscope fixes. It takes only one small glitch for this to be an expensive piece of space junk

JWST operates mostly in the far infrared where there are a lot more tolerances vs visible light telescopes. The new gyros are a totally different technology... much more reliable - less wear items.

There are ways to hedge complexity with redundancy and testing but there is always risk.. I don't think your sentiment is lost on anyone working this project.

Golden Snowflake on a Surfboard (0)

Anonymous Coward | more than 3 years ago | (#35225054)

Looks awfully vulnerable to meteorite strike to me... granted, Hubble was probably just as vulnerable, but this just looks at first glance like a giant target screaming "FRAG ME!" to every passing comet.

Re:Golden Snowflake on a Surfboard (1)

natehoy (1608657) | more than 3 years ago | (#35225642)

Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the drug store, but that's just peanuts to space.
  - Douglas Adams

La Grange point (1, Funny)

Hatta (162192) | more than 3 years ago | (#35225064)

They've got a lot of nice telescopes out there. Haw haw haw haw.

Obligatory (1)

Takichi (1053302) | more than 3 years ago | (#35225084)

Obligatory Perry Bible Fellowship reference: Photo Album [pbfcomics.com]

The future of telescopes. (1)

Facegarden (967477) | more than 3 years ago | (#35225290)

The real future of telescopes will have no mirrors.

I'm not sure why no one has made a big deal out of this, but superconducting cameras have the potential to completely replace mirrors in telescopes, making them more robust and essentially eliminating complex alignment.

Why do I say this? Well, I reasoned this out myself, so maybe I'm wrong, but basically superconducting cameras are able to register every photon that sees them, sending off ~18000 electrons per photon hit. CCDs, on the other hand, send off 1 electron for every photon hit (I read that a while ago but I think those are the numbers).

Since CCD sensors are so much less sensitive, we use massive mirrors to magnify the amount of light hitting the sensor.

Well, it seems to me that if we had high resolution functional S-CAM sensors, we wouldn't need mirrors. We could just point them straight to the sky, and even if 18000 times fewer photons hit them, they'd have roughly the same or better output as a CCD.

Or, you could just lay out a giant array of S-CAM pixels, say, 10 meters in diameter. Then you'd basically have a ten meter telescope without the mirrors, *and* it would be vastly more sensitive.

I understand that using superconductors is currently an enormous pain in the ass, and I'm not expecting us to find a room-temp one any time soon, but even with the complexities of keeping the sensor cool, wouldn't that have enough advantages over a traditional system that it might be worth it? Maybe not yet, as the sensors currently have to be 0.3K, which seems to me to make it extremely challenging. But if we could make them with something warmer - say, liquid nitrogen cooled - then they might be viable.

Is there any flaw in my basic reasoning? I mean, maybe it would be more expensive than I imagine, but I feel like we should be looking into it. Imagine a football-field sized array of S-CAM sensors. I feel like we could pretty much see license plates on alien worlds at that point. And it wouldn't be nearly as fragile as something with a mirror.

http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=36685 [esa.int]

That is the third generation superconducting camera sensor that the ESA is working on. It only has 120 pixels, but I really believe we should be putting way more money into researching these...
-Taylor

Re:The future of telescopes. (0)

Anonymous Coward | more than 3 years ago | (#35225662)

Hmm, you might be right about telescopes not needing the same size mirrors to see the same objects, but you do realise you need a mirror or lens of some sort to focus the light don't you?

Also given that you need a mirror/lens then a bigger one is still better since it increases the resolving power of the telescope - it's not just about capturing more light, though this is an important function of a big mirror.

Finally even though a 18,000x jump in sensitivity would be a really big deal in terms of seeing much dimmer/more distant objects, there are probably still loads of even dimmer and even more distant objects so big mirrors will still be desirable.

Re:The future of telescopes. (0)

Anonymous Coward | more than 3 years ago | (#35225722)

Sorry, but yes, you are wrong. Your idea demonstrates a misunderstanding of both basic quantum mechanics and basic optics. Don't be discouraged by my reply, though. I commend your effort and hope you study up on both subjects and continue dreaming big!

#1) Based on public specs, IR CCD detectors already have a quantum efficiency >70 (e.g. the Hawaii-2RG's used in the JWST program). Getting the last 30% is nice, but hard. It would allow us to build a telescope with a primary 30% smaller in area, but not remove the need for a telescope altogether. The gain in the amplifier (e.g. 18,000 e-/photon) afterwards doesn't *really* matter, since you are still fundamentally limited by the incoming photon (a.k.a. shot) noise in astronomical applications. There is NO WAY AROUND THIS. It is a fundamental limit imposed by quantum mechanics.

#2) An array of phase-insensitive detectors floating in space is sensing the wrong thing. If you collapse the image plane down to the entrance pupil, you will just be measuring the amplitude of incident light (for a star, the field is very accurately approximated by an electromagnetic plane wave... so every pixel in your hypothetical telescope detector will just output the same value). You NEED the optics in front of the detector to turn the phase of the electric field in the entrance pupil to an actual angle (or equivalently, the position at the image plane)

So to recap... a floating array of detectors is not going to replace telescopes :

- we are already 70+ % of the way to perfect in terms of quantum efficiency being flown on the JWST... the last 30% is no paradigm changer.
- you still need :
A) Tons of aux. hardware for calibration, filters for doing science, etc. etc. Since there are no demangified planes conjugate to the detector, each of these would now have to be the size of your HUGE detector array!

B1) Optics to bring things to focus at an image plane
-or-
B2) A detector capable of recording both the phase and amplitude (which in turn, requires large optics to create the holographic reference, interferometer, etc. etc. etc.).

Re:The future of telescopes. (1)

blincoln (592401) | more than 3 years ago | (#35225846)

Even with the most sensitive detector possible, you still need a lens to focus the image. Otherwise you've just got a very fancy flatbed scanner, and everything further away than a couple of inches will be a useless blur.

The lens can be virtual, like in synthetic aperture systems, but building something like that for optical wavelengths with literally *no* physical lenses involved (whether those lenses are glass, mirrors, or whatever) on a football-field-sized scale would be challenging at best. Each photosite on each of your supercooled sensors would need to capture phase information as well as amplitude. The system would also have to store timestamps for each pixel with atomic clock-level accuracy in order to use the phase information. I think some day, the human race will build something like that, but it's probably going to be awhile.

Re:The future of telescopes. (1)

Facegarden (967477) | more than 3 years ago | (#35225994)

Even with the most sensitive detector possible, you still need a lens to focus the image. Otherwise you've just got a very fancy flatbed scanner, and everything further away than a couple of inches will be a useless blur.

The lens can be virtual, like in synthetic aperture systems, but building something like that for optical wavelengths with literally *no* physical lenses involved (whether those lenses are glass, mirrors, or whatever) on a football-field-sized scale would be challenging at best. Each photosite on each of your supercooled sensors would need to capture phase information as well as amplitude. The system would also have to store timestamps for each pixel with atomic clock-level accuracy in order to use the phase information. I think some day, the human race will build something like that, but it's probably going to be awhile.

Ah. Yeah, I was wondering about optics.

Well, it would still allow much smaller mirrors to be used, right? So something like a (relatively cheap) 30" mirror with an S-CAM sensor would be able to outperform a much larger telescope with a CCD?

Even if there are optics involved, making the sensor 18000 times more sensitive seems like it would be immensely more helpful than just making bigger optics.

Re:The future of telescopes. (1)

ogre7299 (229737) | more than 3 years ago | (#35226432)

You still have to contend with the diffraction limit though, 100% efficiency be damned if you can't resolve anything. Also, CCDs are not as ineffecient as you are purporting them to be; they are as efficient as ~90% at some wavelengths (http://www.astronomy.ohio-state.edu/MDM/MDM4K/qe.jpg); therefore, getting 100% effeciency is not going to increase your signal as significantly as you seem to think.

Re:The future of telescopes. (1)

ogre7299 (229737) | more than 3 years ago | (#35226486)

I missed a point here, you seemed to be implying using these for optical interferometry. However, we cannot currently digitize an optical signal and current optical interferometers use analog methods to create interference fringes. At radio wavelengths we can simply downconvert the signal so something more manageable and then calculate the antenna-antenna the interference.

Re:The future of telescopes. (0)

Anonymous Coward | more than 3 years ago | (#35225884)

Or, you could just lay out a giant array of S-CAM pixels, say, 10 meters in diameter. Then you'd basically have a ten meter telescope without the mirrors, *and* it would be vastly more sensitive.

yea right. And the imaging part for this sensor is exactly where? Just putting a sensor in space will give you white noise at best. You can never get rid ofsome focussing optics - be it lenses or mirrors. And mirrors are very robust as compared to lenses.

Re:The future of telescopes. (0)

Anonymous Coward | more than 3 years ago | (#35225990)

You need mirrors or lenses not just to intensify the light hitting a pixel on the receiving device but also to prevent light from extraneous sources hitting that pixel. In other words, what you are suggesting is similar to exposing a roll of film outside a camera and expecting to see the an image of an object formed on it. Without a lens/mirror, light from all directions can hit each pixel of the receiver. Superconducting cameras may be a misleading name because the are just more sensitive detecting devices ; they need to be installed into a telescope to work properly.

I'd Rather... (0)

Anonymous Coward | more than 3 years ago | (#35225310)

I'd rather have more Kepler clone telescopes then Hubble clones. Hubble takes pretty pictures but Kepler is actually finding freaking planets!!

Building it is the easy part. (1)

codepunk (167897) | more than 3 years ago | (#35225520)

Building one is the easy part, launching it into orbit is another matter entirely.

Are La Grange points safe for satellites? (1)

GodfatherofSoul (174979) | more than 3 years ago | (#35226026)

Seems like a natural gravity pit wouldn't be the best place to hang out.

Re:Are La Grange points safe for satellites? (1)

AikonMGB (1013995) | more than 3 years ago | (#35226126)

L1, L2, and L3 are not stable (if you stick a rock there, it will fall away in "no time"). JWST is going to be placed at L2 (though it will move around a bit in a halo orbit). Only L4 and L5 are stable.

Aikon-

Why such a high orbit? (1)

sdguero (1112795) | more than 3 years ago | (#35226106)

I RTFAs and still can't figure out why it has to be further out than the moon to get good pictures. Shouldn't it be able to take nice pics in LEO? Why so far away?

It seems like it'll be next to impossible to fix if anything goes wrong, like it did over and over again with Hubble.

Re:Why such a high orbit? (2)

AikonMGB (1013995) | more than 3 years ago | (#35226162)

JWST's optics and sensors have to be kept very cold, something that is difficult to do in LEO thanks to all of the Earth IR and albedo. Putting it at L2 means the Earth's disturbances will be in line with the Sun's, and they can use a single stationary shield to protect the optics and sensors.

But yes, you are right, it will be significantly more difficult (impossible with current technology) to service it.

Aikon-

"trumps Hubble" (3, Funny)

Lemmy Caution (8378) | more than 3 years ago | (#35226184)

OK, I have no productive contribution here, but the phrases "Hubble trumping" and "trouble humping" are now echoing through my head.

I hope they get it right first time this time... (1)

Rhodri Mawr (862554) | more than 3 years ago | (#35226268)

http://en.wikipedia.org/wiki/Hubble_Space_Telescope#Flawed_mirror [wikipedia.org]

With tolerances at the micron level and such a remote location (doubly so, given the forthcoming decommissioning of the Space Shuttles), they'd better get it right first time this time and build in far more redundancy than the Hubble Telescope has. I'm reminded of the opening chapter of Mostly Harmless by Douglas Adams...

Up close and personal... (1)

ubercam (1025540) | more than 3 years ago | (#35226382)

I've been lucky enough to have had a peek inside one of the cases (as it was being built and having the kinks ironed out) they're going to use to transport the reflector sail things from the manufacturer to the assembly plant, one case per sail. My friend is the shop's computer guy. The case was enormous and had to be perfectly air tight so it could be filled with nitrogen to protect the sail during transport. I saw it in July so I'm pretty sure they've finished and shipped them all by now.

Granted, it wasn't a component of the actual spacecraft, but an important piece of the puzzle nonetheless. I still think it was very cool to have had the privilege of poking my head inside, snapping a few photos and chatting with the guys making it.

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