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NASA Space Science

NASA and DoE Team On Dark Energy Research 106

Posted by timothy
from the what's-the-opposite-of-illuminati? dept.
Roland Piquepaille writes "NASA and the U.S. Department of Energy have teamed up to operate the future Joint Dark Energy Mission. As you probably know, recent astronomical measurements have showed that about 72% of the total energy in the universe is dark energy, even if scientists don't know much about it, but speculate that it is present almost since the beginning of our Universe more than 13 billion years ago. The JDEM 'mission will make precise measurements of the expansion rate of the universe to understand how this rate has changed with time. These measurements will yield vital clues about the nature of dark energy.' The launch of a spacecraft for the JDEM mission is not planned before 2015."
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NASA and DoE Team On Dark Energy Research

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  • by MosesJones (55544) on Friday November 28, 2008 @05:21AM (#25914681) Homepage

    Come on.... "Dark Energy" this should have everyone wearing some form of mask and a black uniform with just a simple white spark on it or something. We complain about not getting kids into science and then when we get something with one of the coolest sounding names around we make it into something dull and boring.

    "Dark Energy has been around for 13 billion years but no-one has been able to harness it. Do you have what it takes to join the Legion of Dark Scientists?"

    • Dude, this has been around for ages... didn't Enron market this??
    • by Andr T. (1006215) <andretaff&gmail,com> on Friday November 28, 2008 @06:51AM (#25915005)
      The mascot could be Darth Vader!

      Mechanical voice:

      - Come join us understand the real nature of the Universe. Together we will understand the deepest secrets of matter and energy...

      Darth Vader approaches a group of scientists wearing white clothes, looking at a telescope and talking to each other.

      - And you can be sure the smartest minds of the planet will be with you in this journey. May the energy, dark and bright, be with you, my friend.

    • They [wikia.com] have already taken over. Grab a crowbar and follow Freeman. He is our only hope.

    • by SpectreBlofeld (886224) on Friday November 28, 2008 @11:47AM (#25916781)

      Lindsay: Yes. For example, no one was showing up for jury
                      duty, so we made the experience more exciting by
                      synergizing it with his comic book collection.

                      [cut to Moe's tavern. Moe opens an envelope]
      Moe: [reading] You have been chosen to join the Justice
                      Squadron, 8 a.m. Monday at the Municipal Fortress of
                      Vengeance. Oh, I am *so* there!

  • by EachLennyAPenny (731871) on Friday November 28, 2008 @05:23AM (#25914685) Homepage
    Once they form the Department of Dark Energy they could post job ads reading "Come to the dark side".
  • Seriously if I was the person managing the DoE budget and I saw something that say "dark energy research" I would think it was a practical joke.

    I know it's called dark energy, but since when has astronomic phenomenon been within the realm of the Department of Energy. The DoE is responsible for energy policies. I could understand investment in potential energy producing technologies, but there is not one scientist who could tell me how to harness dark energy. Let NASA figure out what it is and when NASA says

    • by boot_img (610085) on Friday November 28, 2008 @06:13AM (#25914883)

      Actually DOE has always been deeply involved [doe.gov] in high energy (particle physics) research. They fund a number of accelerators, including Fermilab. Its not clear that any of that research would lead to usable energy sources either.

      You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).

      • by julesh (229690)

        You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).

        Except, I don't really see how high energy physics is involved. I mean, it's not as if anybody has proposed a high-energy experiment that could detect it.

        • Re: (Score:3, Insightful)

          by boot_img (610085)

          Except, I don't really see how high energy physics is involved. I mean, it's not as if anybody has proposed a high-energy experiment that could detect it.

          Ultimately, there must be a particle-physics-based explanation for Dark Energy, whether from string theory or something other theory.

          And just because Dark Energy not accessible via "classical" accelerator experiments, this does not mean that it should not be considered experimental particle physics research. In other words, instead of using a ground-based accelerator, the Universe is the "poor man's" accelerator [discovermagazine.com].

      • by Shag (3737) on Friday November 28, 2008 @09:13AM (#25915635) Homepage

        Actually DOE has always been deeply involved in high energy (particle physics) research. They fund a number of accelerators, including Fermilab. Its not clear that any of that research would lead to usable energy sources either.

        Good so far.

        You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).

        Yes, but don't forget that DOE has its own cosmologists, too. The DOE end of JDEM is being handled by Lawrence Berkeley National Laboratory, which has quite a bit of stuff [lbl.gov] going on in cosmology, mostly under its physics [lbl.gov] division.

        (I [lbl.gov] do some work with one of the collaborations [lbl.gov] based there.)

  • Once scientists understand that space and matter is the same thing (something you should be able to test and prove here on earth) they should understand that dark matter is just space.

    What they're doing by measuring the anomalies with galaxies, and on the smaller scale by making atoms clash together in large colliders, and looking at the results is basically just measuring an effect, and it's really interesting that they aren't doing it with a clear understanding about what they're measuring or why.

    What I m

    • by blancolioni (147353) on Friday November 28, 2008 @06:20AM (#25914897) Homepage

      Of course being a couch-scientist (worse than amateur scientist), I might be hugely wrong, but somehow, I don't think I am (surprisingly).

      Unfortunately, you are wrong, and I guess it's not that surprising, considering your ... interesting take on cosmology. Einstein's work was intimately concerned with the nature of spacetime, so saying that "he looked soley[sic] at matter" is flat-out wrong.

      Space and matter are the same? Then either space has a gravitational effect, or they're the "same" in a way that doesn't include a fundamental property of matter, which is to say that they're not the same at all (you'll recognise the quote "in exactly the same way that bricks don't" -- it speaks to nature of classification rather elegantly I think).

      So why hasn't the gravitational effect of space been detected? Oh, wait, because the scientists missed something. Silly scientists!

      • Re: (Score:3, Interesting)

        by Ambitwistor (1041236)

        Space can have a gravitational effect: in general relativity, gravity gravitates. A black hole is a vacuum solution of the Einstein field equations. And if you object to it being vacuum because you can't say what's at the singularity, there are non-singular vacuum solutions too, like gravitational geons [wikipedia.org]. However, they're not stable, so attempts to describe matter as pure space have failed. (Another attempt which also largely failed is to describe particles as wormhole mouths.)

        Some people think that dark

    • Re: (Score:3, Insightful)

      by Ambitwistor (1041236)

      Once scientists understand that space and matter is the same thing (something you should be able to test and prove here on earth) they should understand that dark matter is just space.

      Although attempts have been made to unify matter and space (see Wheeler's geon idea), they've all failed. Matter and space appear to be different. But even if they were unified, so what? What's the practical difference between "matter which is secretly some aspect of space" and "matter"? I mean, I can say that an electron is really just "space", but that doesn't prevent it from acting like matter.

      it's really interesting that they aren't doing it with a clear understanding about what they're measuring or why.

      They have quite concrete ideas of what they're measuring. They just don't happen to agree with your pet ide

  • by Ignis Flatus (689403) on Friday November 28, 2008 @06:06AM (#25914857)
    if there's so much dark energy in the universe, then why don't we have any local in our own little solar system or planet? how come dark energy only makes the science of things far away off-kilter, yet all our science locally we can measure to 9 or more decimal places? seems like an awfully big fudge factor, if you ask me.
    • Re: (Score:2, Insightful)

      by powerspike (729889)
      maybe it's like fog, when it's far away it looks like a solid cloud.
      When it's close, you can see it even thou your standing in the middle of it, it looks completely different, yet the same thing.
    • by HonIsCool (720634)
      Most of the universe is space, right? Matter clumps together in formations such as planets and stars, but most of the solar system consists of space. Same for galaxies, and clusters. So, if something were to permeate all that space, well, the density wouldn't need to be very much to still have a large effect. So, if dark energy exists, it will also exist here, but the local effect is too small to measure, and only when looking at a much bigger picture can we see something. Well, that's my lay man understa
    • by julesh (229690)

      if there's so much dark energy in the universe

      AIUI, dark energy is theorized to be everywhere. Including within our own solar system. However, the amount of it in any given space is tiny. Current best estimate is 10^{29} grams per cubic centimeter, which is basically nothing. We can't detect that on any reasonable space. It's only because huge quantities of it are (theorized to be) scattered in the vast distances between galaxies that we are able to detect any effect of it at all.

      • by julesh (229690)

        I wrote:

        Current best estimate is 10^{29} grams per cubic centimeter

        Somehow a minus sign got deleted from that post. I blame slashdot's unicode filtering.

        That should, clearly, be 10^{-29} g/cm^2.

    • by boot_img (610085) on Friday November 28, 2008 @07:38AM (#25915203)

      According to the current theory, dark energy does exist in our solar system, its just that you need many, many more than only 9 decimal places to measure it.

      Its repulsive effect however increases with scale, so the larger distances you probe, the easier it is detect.

    • by Ihmhi (1206036)

      Even though it's 72%, we have those great laws of probability to thank for that.

      Let's say I shoot a basketball from the free throw line for 100 shots and I get in 43 of them. From that small set of data, one could say I have a 43% shot accuracy at the free throw line.

      Now if I were to make another 100 shots, I wouldn't get exactly 43. I may get more or less, but 43 would be a good representation of an average.

      In the case of the dark matter, just because the estimate is that it comprises 72% of the universe d

      • Re: (Score:3, Informative)

        by Ambitwistor (1041236)

        Dark matter doesn't have anti-gravity effects. The whole reason why it was postulated in the first place was because of its positive gravity effects: to explain the "missing mass" contributing to galactic rotation curves.

        It doesn't exactly have "anti-" light effects. The main working theory is just that it doesn't interact with light (electromagnetic radiation), because it's not electrically charged.

  • I was always a skeptic when it came to Dark Matter(I am not an astronomer, so this all technically an uniformed opinion). But now I know that it really is all a load of idle speculation coupled with incomplete investigation, and an excessive dose of hype. It only took a few minutes of googling to come up with this paper [arxiv.org].

    One of the biggest pieces of evidence for Dark Matter is the Galaxy Rotation Problem [wikipedia.org]. Basically the rotations of Galaxies do not behave as astronomers expect them to do, leading to the hypothesis that there is more matter in them that we cannot see, "Dark Matter". The velocity profiles that Astronomers expect to see are Keplerian. That is, they expect star systems in galaxies to behave like planets in solar systems when it comes to orbit speed and distance from the focus of rotation.

    The bottom line is, as shown in the paper, this assumption is totally unjustified. The integrals in the 2D galactic disc case do not work out using Shell Theorem [wikipedia.org], which cannot be applied. They are instead quite nasty singular integrals, but twenty minutes with MATLAB and the "QUAD" function will be all it takes to see that basic gravitational theory most certainly does not predict that Galaxies should have Keplerian(Solar System-like) rotation curves, and there is no reason whatsoever for astronomers to assume this. It's all basic mathematical physics well withing the reach of many reading this post.

    The galactic rotation problem is not evidence for Dark Matter. It is only evidence of the need for more applied mathematics courses in astronomy undergraduate degrees. Of course the Galactic rotation problem is not the only evidence for Dark Matter, but it is a big part. The other big piece of evidence was the Galactic Cluster mass problem. It's been a while since I read the relevant papers, but as I recall, Zwicky played hard and fast with the virial theorem, in particular making assumptions about the stability of Galactic clusters.

    Again of course, I am not an astronomer. I am essentially a lay person in these matters, so my posts and opinions (not only in this thread) should be taken with a pinch of salt. Still, I stand by my overall skepticism of Dark Matter theories, and I stand quite firmly on my objections to the interpretation of the Galactic rotation problem. I expect that in the near future, as our ability to analyse and simulate galatic dynamics improves, Dark Matter will finally be debunked.

    • by Andr T. (1006215) <andretaff&gmail,com> on Friday November 28, 2008 @06:36AM (#25914965)
      Dark matter is not the same thing as Dark energy. There are separate theories about each one of them.

      And even if Dark Matter/Dark Energy really does not exist, I think it's justifiable that people search for it. If the experiments don't match what the scientists say about it, we'll know we need another explanation. The money will not be spent in vain.

    • Re: (Score:3, Insightful)

      by julesh (229690)

      Echoing what Andr. T said in his previous post, but in hopefully a little more detail: the evidence for Dark Energy is completely orthogonal to that for Dark Matter. Like you, I'm not an expert on this subject but have done a little reading, and find the D.E. evidence a lot more convincing. Unless there's something fundamentally wrong with general relativity and our understanding of its implications, there is some kind of repulsive force acting on galaxies to push them away from each other.

      Now, I'm not to

    • Re: (Score:3, Insightful)

      by Xelios (822510)
      My problem with both theories is that they seem to be band-aids applied to current physics to tweak the result to something that matches our observations. For example, we assume that general relativity works the same for superclusters of galaxies as it does here in our solar system. Problem is the results it gives don't match our observations. So is this evidence that the theory breaks down over very large scales? Nope, it just means the universe is mostly made of invisible energy with negative pressure tha
      • by Xiroth (917768)

        Unfortunately, it does generally take a genius to take the big leaps in our understanding; to forge all our data and half-truths into a coherent whole - that's why it took 200 years (as it turns out, the amount of time between one genius (Newton) and the next) to solve the last one. With the greater number of people studying science and higher accessibility in the world today, hopefully it'll take less time before the next one in the field emerges. Let's hope.

        • by Andr T. (1006215)
          OK, I understand what you said here, but saying that Physics was 'stuck' for 200 years is a little too much, don't you think? And between Newton and Einstein there were, many, many genius. Faraday, the Curies, Bohr in the same time as Einstein, Planck too. Physics was not stuck.
          • by Xiroth (917768)

            Sorry, I was referring to that specific field - our understanding of light. Not to denigrate all the good work in other fields.

      • Re: (Score:1, Interesting)

        by Anonymous Coward

        What is the purpose of a theory?
        If it is to explain observations already made and to make testable predictions about phenomena that have yet to be observed, then the aether theory (which you admit made pretty accurate predictions) served its purpose. Newton's "Laws" still reign in many domains, as their predictions are accurate to useful limits of observation. General Relativity and Quantum Mechanics are clearly incomplete, yet within certain domains, they produce predictions that match observation to the

      • Re: (Score:3, Insightful)

        by Ambitwistor (1041236)

        My problem with both theories is that they seem to be band-aids applied to current physics to tweak the result to something that matches our observations.

        That's how science works. If you see something anomalous, you start by applying the most minimal possible tweak to explain the anomaly. If that doesn't work, you expand your hypotheses to be more radical until you hit upon something that works.

        As it happens, the most vanilla, boring possible modification — a cosmological constant — seeems to explain our observations, agreeing with both supernova luminosity-redshift relations and the cosmic background radiation angular power spectrum. That dis

      • Re: (Score:1, Informative)

        by Anonymous Coward

        I think you're confused. It wasn't Einstein that debunked the ether theory, it was Michealson and Morley in 1887:

        http://en.wikipedia.org/wiki/Michaelson-Morley_experiment [wikipedia.org]

        More research, less blather, please.

    • by Ginger Unicorn (952287) on Friday November 28, 2008 @07:38AM (#25915201)

      Does this temper your skepticism any? [stanford.edu]

      I find it hard to accept the idea that some lone guy on slashdot has found a problem in the maths used by all the astronomers in the world who describe galaxy rotation, or indeed that even if you had, it seems galaxy rotation is not the sole piece of evidence for dark matter [wikipedia.org].

    • Re: (Score:3, Informative)

      by boot_img (610085)

      It only took a few minutes of googling to come up with this paper [arxiv.org].

      Note that "this paper" has not yet been refereed and accepted by a journal. It is conventional, when submitting papers to arxiv, to indicate to what journal the paper has been submitted, whether it has been refereed and accepted or not. There is none of that information here. Normally a paper submitted in March 2008 would have been accepted and published by end of Nov 2008 if it had been. I suspect that it has been rejected.

      • The key problem with this view is that even if the paper is accurate, based on observation and experimentation, and is reproducable, if it's outside the current dogmatic system it will be rejected.

        Look up Halton Arp, Peter Duesberg, and Immanuel Velikovsky. The latter, for using all available evidence to construct a wildly different view of the solar system that matches history, was ignored, criticized without the critic having read his work as unscientific or being biblically based, when in fact all his r

        • by boot_img (610085)

          I am an astronomer. I don't know about Duesberg or Velikovsky, but I can tell you that Halton Arp's theories do not agree with the available evidence.

          Contrary to the romantic notions of some, there is no "conspiracy" against him. There is a sound, rational reason that he is ignored: its simply that his ideas do not match the observations.

        • I'm sorry, but Velikovsky spent most of his time attempting to match his own interpretation of various Biblical events to the solar system... and he didn't even match the timeline accepted by biblical scholars, much less the scientific evidence.

          Honestly, anybody who actually has read ‘Worlds in Collision’ and compared it with actual historical events is more likely to come up with ‘Wow, isn't it amazing how much people can spend enormous amounts of effort to create patterns even where none

          • There are perfectly good examples of scientific orthodoxy trying to shut up inconvenient facts. Einstein himself tried to destroy quantum theory, when he'd helped create it with his work on the Photoelectric effect.

            That's one of the worst examples you could have picked.

            Einstein never tried to destroy quantum theory, and he never tried to "shut up inconvenient facts". Einstein liked quantum theory. He just didn't like the non-deterministic Copenhagen interpretation. And he wasn't just irrationally denying facts. He had damn good arguments and thought experiments to support his view, which although ultimately proven wrong, ended up advancing our understanding of quantum theory (such as the EPR paradox). Bohr was hi

    • by Ummite (195748)
      We have a scientist, named "Jean-Pierre Petit" (see wikipedia). He predicts some of galaxy configuration. Please read his paper, it's interesting.
    • by VShael (62735)

      I think you're quite right, and hence the use of the "epicycle" tag on this story.

      Epicycles, if you don't know, were the artificial additions to the "circular" orbital theory, which became more and more clumsy and unwieldly, until some bright spark called Copernicus simplified the whole thing. And then when we finally worked out orbits were elliptical, not circular, we looked back on epicycles and said "Of course! How could we have been so stupid!"

      Epicycles. Dark Matter.

      • There's nothing wrong with epicycles as a theory. It's just Fourier analysis. The real problem with epicycles is not that they're wrong, but they're not predictive. (There's no theory to say what the Fourier coefficients ought to be.)

        Dark matter is not like epicycles. You can put in assumptions about dark matter inferred from one set of observations (e.g., galaxy scale physics), and make predictions about different observations (e.g., the cosmic background radiation), and you find that the predictions w

    • Re: (Score:3, Insightful)

      by Ambitwistor (1041236)

      I was always a skeptic when it came to Dark Matter(I am not an astronomer, so this all technically an uniformed opinion). But now I know that it really is all a load of idle speculation coupled with incomplete investigation, and an excessive dose of hype. It only took a few minutes of googling to come up with this paper.

      Oh yeah. A few minutes of Googling turns up an unpublished manuscript which overturns 80 years of research and thousands of papers. A manscript written by a guy who runs a mail-order crystal business and a former Xerox employee who studies fluid droplets. (I bet I'm going to hear "but Einstein was a patent clerk" real soon now ...) Which cites Electric Universe theory papers. That's totally credible.

      It is only evidence of the need for more applied mathematics courses in astronomy undergraduate degrees.

      Yeah, everyone who has worked on dark matter flunked basic undergraduate astronomy. That's probably it.

    • There were already better evidence with gravity lensing or something like that. The evidence for dark matter keeps growing larger and larger.
    • You should check out James P. Hogan's Kicking The Sacred Cow. It presents a variety of alternate, observationally/experimentally proven alternatives to the mainstream view that have been ignored or flat out rejected by the dogmatic mainstream science. Such as that an electromagnetically formed plasma universe concept actually explains everything. Or that "Dark Matter" is really just molecular hydrogen (H2), which isn't detected easily, but is far more prevalent than atomic hydrogen. As well as a variety
    • by syousef (465911)

      I have a masters in Astronomy but have never worked in the field and it's the kind of degree more suited to teaching than research. Nevertheless...

      I skimmed the paper and I don't think it's saying what you think it's saying.

      From section 4 (2)
      "By contrast, others inaccurately assume the galactic mass distributions follow
      the measured light distributions (approximately exponential), and then the measured rotational
      velocity curves are not duplicated. But this assumption of a simple direct relationship between
      li

  • Is it true that, presuming one can't grasp it, dark energy doesn't not matter ?
  • Bush even got it into an arms research race with the Protoss!

  • by PolygamousRanchKid (1290638) on Friday November 28, 2008 @08:12AM (#25915347)

    If NASA and the DoE start yanking on the Dark Energy in the Universe, they might find that attached to the other end are . . . Dark Energy Creatures.

    They might not be amused with the antics of NASA and the DoE.

    "Hey, you, Earthling! Is this your Joint Dark Mission Probe, that just broke my window?"

    You have been warned.

  • I'm surprised by the low quality of comments so far. Must be the fallout from Turkey Day here in the US... Anyways, Dark Matter and Dark Energy are two very different concepts. Dark Matter is what makes the universe clump together. Galaxies are just the markers or highlights in the densest spots of the Dark Matter distribution, pretty much like foam on the tips of waves. There's plenty of observational evidence besides rotation curves. Simulations of the evolution of the universe these days are pretty much
  • So that is what a ZPM gets it's power from now we need a way to make them and we better do that off world.

  • This will kill my karma, but I just have to ask: isn't all this "something we can't see that's messing up our physics" putting us off the possibility that our physics models may just be flat out wrong?

    I mean, would we have a relativity theory if Einstein had stuck to Newtonian physics and stated that the errors measured were caused bay some misterious force/matter/energy that we couldn't see?

    • This will kill my karma, but I just have to ask: isn't all this "something we can't see that's messing up our physics" putting us off the possibility that our physics models may just be flat out wrong?

      Yes, and that's why various dark energy theories introduce new physics (such as new types of particles or modifications to gravity).

      I mean, would we have a relativity theory if Einstein had stuck to Newtonian physics and stated that the errors measured were caused bay some misterious force/matter/energy that we couldn't see?

      Would we have discovered Neptune if we had tried to invent new physics instead of postulating that some unseen body was perturbing the orbit of Uranus?

      Anyway, Einstein's solution was to modify Newton's theory of gravity. The leading solution is to modify Einstein's theory of gravity by adding a cosmological constant. (Actually, it's really just restoring Einstein's theory to

  • For those wondering why the Department of Energy is building a space telescope rather than focussing on nuclear things, the Department of Energy funds the SLAC Linear Accelerator centre at Stanford and it's people at that centre who have designed SNAP, a spacecraft that happens to fulfill exactly the requirements NASA put forth for JDEM.

    The Dark Energy Mission is a wide-field high-resolution space telescope; a hundred million or so pixels of 0.2 arcsecond extent, and a five-foot main mirror. The idea's to

    • by Shag (3737)

      For those wondering why the Department of Energy is building a space telescope rather than focussing on nuclear things, the Department of Energy funds the SLAC Linear Accelerator centre at Stanford and it's people at that centre who have designed SNAP

      Uh... not to fan the flames of any Bay-Area turf wars, but that team [lbl.gov] is led by people from Lawrence Berkeley National Laboratory and University of Califoria at Berkeley. Yes, there are a couple Stanford people who work on things like electronics and pointing, but they're a small fraction of the whole project.

      You were close, though: the Department of Energy funds Lawrence Berkeley National Laboratory. :)

  • I'll wager that this dark energy stuff is actually laziness, and there's heaps more of it than anyone ever imagined.

What this country needs is a dime that will buy a good five-cent bagel.

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