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Science Technology

Listening for Deuterium 87

Posted by ScuttleMonkey from the but-can-you-dance-to-it dept.
jose parinas writes "Researchers at MIT made the first radio detection of deuterium, an atom that the scientists claim is key to understanding the beginning of the universe." It turns out the actual detection wasn't the key, but filtering out all of the RF 'pollution' produced by nearby gadgets.
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Listening for Deuterium More

Listening for Deuterium

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  • Bad science (Score:2, Informative)

    by Skiron ( 735617 )
    "At times, Rogers asked for help from Haystack's neighbors, and in several instances replaced a certain brand of answering machine that was sending out a radio signal with one that did not interfere with the experiment. The interference caused by one person's stereo system was solved by having a part on the sound card replaced by the factory."

    So how can they prove Mr. Alien doesn't have dodgy sound cards too, and these are giving false positives?

  • Unrea (Score:4, Interesting)

    by elgatozorbas ( 783538 ) on Saturday September 03, 2005 @02:45PM (#13472011)
    The interference caused by one person's stereo system was solved by having a part on the sound card replaced by the factory.

    When these measurements are even disturbed by EMI due to sources that aren't even supposed to be radiating at all, they apparently are very sensitive. Why don't they do them somewhere else, far from civilisation? Also, how can they be sure that what is measured is actually this deuterium and not another very weak terrestrial noise source?

    • If you put things inside a faraday cage then you don't have to worry about outside interferance.

      http://en.wikipedia.org/wiki/Faraday_Cage [wikipedia.org]
    • I hope I'm not redundant but there aren't a lot of places far from civilsation left and most of the remaining areas are not very hopsitable (Antarctica and rain forests are not the best places for doing research if you had a choice). Also the cost of moving hardware and brainpower to the location and maintaining the equipment is usually prohibitive if it is not completely automated and remotely managed. Worse, with high cost the university will probably fund a cheaper, albeit less interesting subject and yo
  • If they can find a good way to locate large amounts of deuterium they will be one step closer to making nuclear fusion a viable source of energy.

    Deuterium [wikipedia.org] reacts well with Tritium [wikipedia.org] in fusion to produce a large amount of energy.
    • I have hard to envision any scenario where power production by fusion, for use on Earth, would be helped by location of deuterium in anything beyond our atmosphere. It's not like the oceans are more dense with it than any gas cloud in space would ever be. (bar a real star or gas giant planet, maybe)

    • Comment removed (Score:4, Informative)

      by account_deleted ( 4530225 ) on Saturday September 03, 2005 @03:01PM (#13472106)
      Comment removed based on user account deletion
      • That's right. One of theses plants belonged to "Norsk Hydro" and was involved in some secret WW2-project. The Nazis tried to produce tons of deuterium-oxide ("heavy water") there for their nuclear scientists. Just have a look here [wikipedia.org]. When Werner Heisenberg in 1942 replied to Nazi ministry of war that a "nuke" would be up to 5 years away, funds were pulled out of this project to further von Brauns rocketry. (For those who can read German, surf here [www.zdf.de].
    • If they can find a good way to locate large amounts of deuterium they will be one step closer to making nuclear fusion a viable source of energy.

      /me points at the big body of seawater [gsu.edu] off the coast near my hometown.

      Tritium is the main problem.

      What they could be used for. [gsu.edu]
    • "The detection of deuterium is of interest because the amount of deuterium can be related to the amount of dark matter in the universe, but accurate measurements have been elusive. Because of the way deuterium was created in the Big Bang, an accurate measurement of deuterium would allow scientists to set constraints on models of the Big Bang."

      We've got a plentiful supply of deuterium, because as the article says about 1 in 100,000 hydrogen atoms is deuterium. Any water molecule can contain one or more deut

    • New Orleans (Score:1, Troll)

      by HermanAB ( 661181 )
      presently has an enormous excess of deuterium...
    • Deuterium + Tritium = ...Pentium!

      (2 + 3 = 5)

  • Why *listen* for deuterium? (Score:3, Funny)

    by payndz ( 589033 ) on Saturday September 03, 2005 @02:59PM (#13472093)
    According to Star Trek: Voyager, you can just dig the stuff right out of the ground as ore!

    What, you mean Voyager's science may not be 100% accurate? You're telling me that gravity isn't radioactive?

    ('Equinox Part II' and 'One Small Step' are the guilty episodes from above, if you were wondering...)

  • Makes you wonder if this could ever have been pulled off if BPL was already widely implemented...

  • Ommmm... (Score:4, Interesting)

    by moviepig.com ( 745183 ) on Saturday September 03, 2005 @03:11PM (#13472168)
    It turns out the actual detection wasn't the key, but filtering out all of the RF 'pollution' produced by nearby gadgets.

    Eliminating camouflage and noise, to see what's in plain sight all along... Sounds somewhat Zen...

  • interesting side values (Score:5, Interesting)

    by zappepcs ( 820751 ) on Saturday September 03, 2005 @03:13PM (#13472183) Journal
    Its interesting that this might bring light to the EMI and RF radiation that is all around us. The work to filter out that noise and reduce it will go quite a long ways toward making wireless broadband more available, toward making things more capable, quiet, and efficient. This amounts to a step toward making RF polution a problem that needs to be addressed. Sort of like taking lead out of computer parts, but taking unneeded and nasty RF out of the airwaves. That would give more spectrum, and better use of the spectrum that is used. This is good.

  • A Useful Link (Score:5, Informative)

    by Detritus ( 11846 ) on Saturday September 03, 2005 @03:16PM (#13472194) Homepage
    Deuterium Array Home Page [mit.edu]

    The signal they are looking for is the 327 MHz emission line of deuterium.

  • Annoying RF (Score:3)

    by Crixus ( 97721 ) on Saturday September 03, 2005 @03:25PM (#13472242)
    I work in recording studios and find RF to be a huge problem every day. Even when using balanced audio. I'm curious to know what methods they are using to get rid of the GIGANTIC amounts of RF pollution they they're encountering.
  • The quality of the "research" coming out of MIT seems to be slipping a bit. It's common knowledge to those who work with EEG devices and other electronics that work in the pico, nano, and micro volt ranges that background noise is the biggest problem to getting useful data. Why it's taken an MIT researcher until 2005 to uncover the same principles that have been known to the rest of the scientific community for 7 decades is a bit confounding. Next thing you know, they'll be releasing a report entitled: "
    • Go read the article. MIT didn't newly discover this principle, they spent the year trying to eliminate its effects.

      If you want to hear a little bit of the Big Bang, you're going to have to turn down your stereo.

      That's what neighbors of MIT's Haystack Observatory found out. They were asked to make a little accommodation for science, and now the results are in: Scientists at Haystack have made the first radio detection of deuterium, an atom that is key to understanding the beginning of the universe.
      • Again, I say... there are a large number of places in the country where similar high-sensitivity experiments are carried out on a regular basis. Apparently MIT's people were just a bit too uppity to ask help from the hundreds of people who already had the solution to a problem that took them a year to resolve.

        • It's common knowledge to those who work with EEG devices and other electronics that work in the pico, nano, and micro volt ranges that background noise is the biggest problem to getting useful data.

          EEG designers deal with their problems mostly by filtering the radio-frequency noise out of their low-frequency signal. The MIT folks are listening to the radio-frequency noise. The only way to make sure the noise is of cosmological origin is to turn off all the local noise sources in that frequency band.

          • But, still, wouldn't that have been easier by going to Arecibo or Green Bank? Granted, neither location will ever be confused with Cambridge, but still...

            Besides, if they went to Green Bank, they could take a railroad ride [cassrailroad.com] during their spare time.

            • Perhaps. Sending people somewhere is expensive, and learning to shoehorn your project into an existing radio telescope doesn't teach you the same things as designing your own. And why not? Building your own is cool.
        • Actually that's not what you said originally.

          Also, they were collecting data that entire year. I can only imagine that it would be easier eliminating local sources of background noise rather than asking for a year's worth of data from a remote location. It would be asking a lot for that remote location, and in addition the researchers involved would have less control over the project.
        • Hm, disregard that last comment, I misunderstood your point. However, see the comment by (negative video)
        • Even if EEGs were high frequency signals, people measuring lab signals could fall back on building a Faraday cage around the whole room to block outside interference...like say, anything from space.
  • Rather than researching the beginning of the universe, shouldn't we be more interested in the [i]end[/i] of the universe? I would rather know how we're all going to be sucked into a singularity.
    • Not that I agree with their logic, but I think they think that if they know what happened in the beginning, they can use that to help figure out what will happen later. My old physics teacher likened it to an apple pie. If you've never made an apple pie before, and you only have the ingredients, it's going to be a lot harder to make one than if you have crumbs from the last pie, even if it was blueberry. Something like that, I'm not entirely sure.
  • Wonder how long until the FCC tries to regulate it...
    • What do you mean? It is already an FCC regulated frequency. According to ITU rules, the frequencies they are listening to" [astron.nl] are already allocated to radio astronomy as primary. You cannot legally operate in these frequencies unless you also have primary allocation. They are reserved for science and some other specific tasks.
  • Technically, this isn't the first RF detection of deuterium. Deuterium Nuclear Magnetic Resonance (NMR) has been around since the 50's and uses RF to excite and receive signals from deuterium nuclei transitioning between quantum spin states that separate in energy when subjected to a magnetic field.

    This may be the first extraterrestrial RF detection of deuterium and as such is pretty neat, but TFA should have been a little more careful.
    • Maybe YOU should've been more careful. Deuterons have integer spin. They're bosons and NMR is useless in detecting them. Thats why heavy water is used as a solvent for organic chem NMR, so the H in water doesn't swamp the signal.
      • NMR is useful for detecting any nucleus with integral or half integral spin - the only thing its useless for is a nuclei with no intrinsic spin.

        Deuterium NMR is actually fairly useful; the deuterium resonance is used in most modern spectrometers as a lock signal to monitor the drift of the magnetic field in which the spectrum is being taken, and maintain spectra which can be averaged together to get a better signal to noise ratio. It's only because deuterium has a different resonance frequency that it doesn
      • Deuterium nuclei do have spin-1, which NMR is perfectly capable of detecting. In fact, many spectrometers use the deuterium NMR signal from deuterated solvents for shimming (compensating for magnetic field inhomogenieties typically introduced by the sample). Nuclei that have spin-0 (e.g. Calcium) are the ones that cannot be detected by NMR.

        As an AC mentioned, the resonance frequency is different, so it just doesn't appear in the 1H NMR spectra. For example, on a commmon NMR spectrometer (7 Tesla), 1H
        • hmmmm well that does make sense doesn't it....

          how do you use the line to shim the field though
          • Basically, you just perform the NMR experiment looking at deuterium and change the current to the shim electromagnets until you have maximized the peak height (thereby minimizing the linewidth). Alternately, you can look at the free-induction decay (FID) and attempt to find the exponentially decaying sinusoid with the longest time constant (which will result in the narrowest peak in the frequency domain). It is the same technique as when you use the proton signal.

            The advantage of using the deuterium s
  • I remember working in our optics lab at Rose, where we had a piece of equipment that kept giving really poor data--obviously a noise problem. I can't remember if it was the spectrum analyzer or what, but we just couldn't figure out where all this noise was coming from.

    Naturally, we blamed it on the EE _power lab_ that was right above us, but I think someone eventually suggested that it might be the ballasts in the fluorescent lights in the room. I just wish I could remember what we were trying to measure
  • Radio waves are light, not sound. They just have a longer wavelength than the light we see with our eyes. Just because we listen to audio signals on radios doesn't mean that radio waves are sound.
    • To get a little more pedantic, audio is used to modulate the RF signal. The modulated RF is then transmitted to a receiver, where the signal is demodulated, the audio extracted, amplified, and then sent to the speaker(s).

  • but it's DILITHIUM we need if we're ever going to get off this godforsaken rock!
  • It turns out the actual detection wasn't the key, but filtering out all of the RF 'pollution' produced by nearby gadgets.

    Thanks for ruining the ending!

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