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Space NASA Science

NASA Takes Step Forward In Planet Finding 105

Posted by Zonk from the i-can-see-my-house-from-here dept.
Spy der Mann wrote to mention a piece at Physorg.com about a major breakthrough in planet finding. From the article: "On a crystal clear, star-filled night at Hawaii's Keck Observatory in Mauna Kea, NASA engineers successfully suppressed the blinding light of three stars, including the well-known Vega, by 100 times. This breakthrough will enable scientists to detect the dim dust disks around stars, where planets might be forming. Normally the disks are obscured by the glare of the starlight. Engineers accomplished this challenging feat with the Keck Interferometer, which links the observatory's two 10-meter (33-feet) telescopes. By combining light from the telescopes, the Keck Interferometer has a resolving power equivalent to a football-field sized telescope. The 'technological touchdown' of blocking starlight was achieved by adding an instrument called a 'nuller.' "
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NASA Takes Step Forward In Planet Finding More

NASA Takes Step Forward In Planet Finding

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  • You can do the same thing at home (Score:5, Funny)

    by Chairboy ( 88841 ) on Friday September 30, 2005 @07:59PM (#13690296) Homepage
    I've replicated the same feat at home using a device I call a "lens cap", except I can significantly beat the 100x reduction of star brightness.

    I'll entertain all bids on this technology...
    • except I can significantly beat the 100x reduction of star brightness.

      Not to mention seeing absolutely no star in the process, for obvious reasons.

      <sarcasm>Good job.</sarcasm> ;)

    • I'll entertain all bids on this technology...

      Would you be interested in going in to partnership? I have a patent pending on my "LALALALICAN'THEARYOU" sound reduction technology.

      We could maybe even go further and suggest NASA license the use of celery in place of those pesky ceramic tiles that keep coming off. Seriously, that stuff is impossible to get to burn and mayo (or other dressing) often becomes incredibly tacky/adhesive after a couple of weeks - it may just have the properties they're after.

      If 3M can
  • When will we get all our instruments to examine space...in space? I can't imagine a scientific reason to look from the crust of a planet for anything in deep space.
  • a beowulf clust... oh, sorry... Just had to do it!
  • Not much detail on the interferometer... is it like umask for light?

    • Re:Interferometer? (Score:5, Informative)

      by MarkRose ( 820682 ) on Friday September 30, 2005 @08:16PM (#13690423) Homepage
      Actually, yes. It uses the interference patterns between the light received at the two (or more) telescopes to give resolution many times that of the individual instruments. http://en.wikipedia.org/wiki/Interferometry [wikipedia.org]

      • Re:Interferometer? (Score:4, Interesting)

        by tsm_sf ( 545316 ) * on Friday September 30, 2005 @08:53PM (#13690669) Journal
        Can this be programmed into cheap telescopes for well known light sources?

        Is this the answer to light pollution?

        I'm guessing that the answer is "no" and "no", respectively, but I'd be interested to find out why not.

        • Re:Interferometer? (Score:5, Informative)

          by StupendousMan ( 69768 ) on Friday September 30, 2005 @10:26PM (#13691087) Homepage
          > Can this be programmed into cheap telescopes for well known light sources?

              No. The technology required to combine two light beams in
          a coherent way is wa-a-a-y more expensive than a "cheap"
          telescope. One must be able to control the length of the
          two paths of light to a small fraction of wavelength of
          the light. In the case of ordinary visible light, that
          means "a small fraction of about 500 nm". That's the
          hard part :-(

          > Is this the answer to light pollution?

              Again, no. If you can perform interferometry, you
          can in effect reduce the size of the field of view, if
          you wish, and therefore reduce the noise contributed
          by background light; but for most purposes, you
          still want to see more than just point sources,
          which means a reasonable field of view, which
          means that there is still plenty of noise from the
          background.

              Alas.

          • The technology required to combine two light beams in a coherent way is wa-a-a-y more expensive than a "cheap" telescope.

            On the plus side, if you want a large aperture to get high resolution, an interferometer with a long baseline will be cheaper than a telescope with a similar resolution. There's a lot less glass to grind, and unless you're trying to make a Fizeau interferometer, you need high precision in fewer places.

          • Re:Interferometer? (Score:1, Funny)

            by Anonymous Coward
            > a small fraction of about 500 nm

            A small fraction of about 500 nautical miles? No sweat, I got that covered. :)

    • Re:Interferometer? (Score:2, Informative)

      by Anonymous Coward
      Here's the how and why of it:

      Bring two beams of light from the same star (but separate telescopes) together, with exactly half a wavelength of extra pathlength added to one of the beams, and the light from one beam will cancel out the light from the other. It's a consequence of the wave-like behavior of photons.

      This happens only for light very close to the optical axis. Light coming from something close to the star won't cancel. So you can use this "nulling" effect to study faint things very close to bri
  • Awww, and I had my luck pinned on my small, 8'' homemade Dobsonian. Second trial run was tonight, and I had expected to find the next Planet Earth! FYI anyhow, it's really easy + inexpensive to make [google.com] your own telescope... and find the next E-type Tw2002 colonizable planet!!! ~d
    • Grinding lenses is a fun father-son hobby! Actually, it's a good son hobby while father has a cool beer (if I remember correctly =)

      • Re:Awww.... (Score:3, Interesting)

        by Zzyzygy ( 189883 ) *
        It is a good father-son hobby. I built my own 8" newtonian about 27 years ago, dad and I spent a lot of time grinding the mirror, heading down to Meade [meade.com] to buy parts, eyepieces, an equatorial mount, etc. I learned more about my father during that nine month project than I had in my previous sixteen years of existence on this ball of dirt we call the earth.

        We had many years of eyepiece time enjoying and documenting our observations

        I still have that telescope, and I think of my recently-departed father w
    • find the next E-type Tw2002 colonizable planet

      That might be tricky, but you could have a shot at your own comet if you work at it.

      rj

    • Article is here [wikipedia.org]. I haven't tried this myself, it looks like a lot of work.
    • E-type Tw2002? Surely you mean an M class planet.
    • Dobson didn't invent anything! Alt-Az mounts have been around for hundreds of years! At least say you have a 8" NEWTONIAN on a Dobsonian mount!
  • The 'technological touchdown' of blocking starlight was achieved by adding an instrument called a 'nuller.' "

    Once again, the importance of nul terminating is illustrated.

    • Re:nuller? (Score:2, Funny)

      by Spoonito ( 849497 )
      "The 'technological touchdown' of blocking starlight was achieved by adding an instrument called a 'nuller.'"

      I wish the New York Jets had a 'nuller' for stopping some technical touchdowns of their own.

  • ...did they receive prime-number transmissions, encoded with an audio/video sideband signal?
    • ...did they receive prime-number transmissions, encoded with an audio/video sideband signal?

      Yes, but they ignored it because it was, "Lower Your Mortgage in Andromeda NOW NOW NOW!"
               
  • Can we use the "nuller" to remove the offending glare from the fake teeth, fake breasts, overdone cosmetic surgeries and massive egos of the Hollywood "stars"?
  • So did those smarty scientists figure out a distinction for planets, then? Is Pluto a real planet or not? I can't believe I missed this! Heh, I figured news that the criteria for what makes a body a planet is set would have been duped twice by now.
    • So did those smarty scientists figure out a distinction for planets, then? Is Pluto a real planet or not?

      Any coherent body large enough to be detected from such a distance is not likely to be near the debate threashold of size. (At least not on the small end, but "failed stars" may present classification difficulties on the higher end.)
               

  • Why!? (Score:3, Funny)

    by damnfuct ( 861910 ) on Friday September 30, 2005 @08:30PM (#13690521)
    The question I have to ask is why are we looking for planets?! It's almost as if we've totally leapfrogged the part where we actually find a way to get INTO space and TO planets. It's like we're kids looking through the window of a bar wanting to taste beer. Instead of looking at beer and wondering if it tastes good, we kids should be forging some fake id's and finding out for ourselves.
    • So you're suggesting that we forget about all astronomy until we have faster-than-light travel?

    • Re:Why!? (Score:3, Interesting)

      by helioquake ( 841463 ) *
      It's not just about finding a planet.

      Despite what people may think, the evolution of stars are still not completely understood. Esp, how do stars affect their neighboring environment? To answer the question, it is important to *look* at their immediate surroundings. But that's hard to do, since the stars themselves are blindingly bright and overwhelms the fainter features around them (e.g., you can't see coronae with your naked eyes, unless the sun itself is eclipsed).

      This technique would allow us to study
    • The question I have to ask is why are we looking for planets?! It's almost as if we've totally leapfrogged the part where we actually find a way to get INTO space and TO planets.

      All part of the plan..

      Imagine the reaction of the government if someone discovers planet with possible signs of life (just life, not sentient..).

      • Indeed. You'd want to ensure they don't have any Weapons of Mass Destruction before you use that as a pretext for invading them using an undersized military presence -- otherwise they'd rip you a new arsehole.

    • People tend to work by goals. If they have something to attain, they tend to attain it. If they see nothing to attain, they tend to do nothing. If we discover a potentially *liveable* planet, the competition to get there will start and things will start to progress much faster.

      Innerweb

  • slightly more info (Score:5, Informative)

    by 1fitz2many ( 409956 ) on Friday September 30, 2005 @08:35PM (#13690561) Homepage
    Here's an older press release [nasa.gov] (with dewar pic) that has a little bit more info. Looks like lab tests were able to provide a null depth of 10^3 vs. 10^2 reported on-sky in the current blurb.

    Finally, since I haven't seen a one sentence synopsis, a nulling interferometer does a careful job making the on-axis starlight received by two telescopes interfere destructively, while off-axis light from circumstellar emission passes through the system. This instrument is designed to study dust emission analogous to the zodiacal light in our own solar system.

    • What you posted could be restated as follows, losing none of the relevant information, and being 100x easier to read:

      "A nulling interferometer does what the moon does during a solar eclipse -- it blocks out the starlight, although instead of simply blocking the light, it removes it using a light interference technique. And just as a total eclipse allows us to view the normally-obscured faint detail around the edge of the sun, a nuller allows astronomers to see the fainter objects around a star that would ot

      • Re:In a slightly less arrogant tone (Score:4, Informative)

        by bitingduck ( 810730 ) on Saturday October 01, 2005 @12:39AM (#13691646) Homepage
        Except that using the moon blocking the light (as in an eclipse) isn't a good analogy for a nuller. The nulling interferometer doesn't have to put in anything to block the light-- it adjusts the relative phase of light on two different paths so that the on-axis light cancels out, but the off axis light doesn't. There are different instruments that work more like an eclipse, where a stop is used to block the startlight but not the planet light.
      • What you posted could be restated as follows, losing none of the relevant information...

        Your analogy might work okay for grandma (who would presumably need to understand the purpose of this technique), but the slashdot target audience is generally a technically-oriented crowd. We're interested in a brief overview of how it works, and we remember a thing or two from those mandatory physics classes we took along the way to computer science, engineering, math, or whatever pure/applied science we got into. As

  • AKA (Score:3, Funny)

    by MoogMan ( 442253 ) on Friday September 30, 2005 @08:51PM (#13690657)
    A "nuller" AKA bluetack.
  • Ok, this is a great result. It does not however deal with the question of planets which have disappeared. Go read the Wikipedia entries on Dyson spheres and Matrioshka Brains. There should be an abundance out there of planets which we cannot see including some which may explain the "dark matter". I am *not* interested in the evidence that gets us to where we are. I am here, I know that works. I am interested in the evidence that suggests where we are going to go.
    • Unless the people in them were, for some reason too advanced for us to know how, storing the energy emitted by the star, a Dyson sphere would be re-emitting all the energy emitted by the star, but at a lower temperature. Therefore, Dyson spheres should be visible in infrared.
      • Agreed and this is what Dyson actually suggested. But our abilities to observe in the infrared are so poor that it is difficult to imagine a situation in which we would observe them. As Minsky pointed out at the Byurakan conference the most advanced civilizations will radiate heat at a temperature slightly above the CMB. So how would you propose we detect them?

        Dyson made one mistake due to the era in which he was thinking. He presumed that "intelligence" must be operating at a liquid water temperatures
    • Question: Why should there be an abundance of massive structures in the galaxy? And more importantly, should there be such a large number, why would no radio waves or interstellar communication be detected? Unless you're suggesting that the species building these massive constructs never discovered radio waves.
  • I always wondered how /dev/null worked. Now I get it. It's a black hole.. nothing escapes it, no naughty data files, not even light!

    Come to think about it, in databases, nulls usually give me my fair share of headaches. Finally, another good use of the null beast!

    6d
  • NASA search for new planets...

    I wondered why they were teaming up with Google... now it makes sense...

  • Looks like Blue Blockers really work. And here I was thinking $40 for a pair of sunglasses was a ripoff.

    D

  • Taking risks (Score:2, Funny)

    by Ogive17 ( 691899 )
    from the article..
    Scientists believe the best odds of finding life outside our solar system are on Earth-sized planets, particularly those with the right temperature, density and chemistry.
    Wow, don't go out on a limb or anything...

  • Google really finds anything... (Score:3, Insightful)

    by Damek ( 515688 ) <.gro.kemad. .ta. .mada.> on Friday September 30, 2005 @10:39PM (#13691153) Homepage
    Wow, planet finding, so that's what NASA was hookin' up with Google for...

  • Informative links (Score:5, Informative)

    by DerekLyons ( 302214 ) <fairwater@@@gmail...com> on Friday September 30, 2005 @11:24PM (#13691367) Homepage
    1. Technical description [nasa.gov] of the interferometer.
    2. A detailed paper [nasa.gov] (PDF file) on the nuller.

  • Let Imaginations Run Wild! (Score:3, Interesting)

    by Zobeid ( 314469 ) on Friday September 30, 2005 @11:51PM (#13691469)
    Right now this is something only astronomers are really interested in. It's kind of sneaking under the radar of the public at large. They are going to get a big shock someday. When the first truly Earth-like planet is discovered, with unambiguous signs of a living biosphere (for example, lots of free oxygen in the atmosphere), the psychological impact will be huge.

    You don't think so? You think it can't really matter because visiting such a planet, or even sending a robot probe, is too far beyond our capabilities? Logically that may be true, but there's more than logic at work.

    Try to imagine what it was like when Galileo pointed his primitive telescope skyward and realized planets weren't mere specks of light -- there were worlds up there! Even though nobody had any idea how to reach them, everyone's view of the universe had to change. From Galileo's time right up through the early 20th century, imaginations ran wild, and every celestial sphere was imagined to be inhabited. There were jungles on Venus, canals on Mars!

    In the last 60 years or so, in some ways our view of the universe has regressed. Now we've looked around our solar system, and it's been a bit of a letdown. Mere specks of light have been replaced by barren balls of rock, or ice, or gas. In their minds, people have started sliding outer space back into the category of the uninteresting and unimportant.

    When the first news comes back of an Earth-like planet. . . when one is shown to have life. . . when we get a fuzzy image of another cloud-swirled blue marble out there somewhere. . . It'll be just like Galileo all over again. Nobody will have any clear idea how to reach those worlds, but imaginations will run wild. And I think that's a good thing.
    • You don't think so? You think it can't really matter because visiting such a planet, or even sending a robot probe, is too far beyond our capabilities?

      It is currently possible. It just takes lots of money and patience. For example, for maybe 2 trillion dollars we could build a multi-generational nuclear powered ship that may take something like 750 years to reach a nearby Earth-like planet.

      Building an unmanned probe would certainly prove interesting because it would have to explore without human feedback b
      • Actually. . . If I'm not mistaken it was church doctrine that the heavenly bodies -- including the sun and moon -- were perfect creations. The dark and light areas on the moon were assumed to be a blurry image of the Earth reflecting from the moon's flawless mirror surface. The various "seas", craters, and other lunar features weren't recognized and named until after the telescope came along.
    • Right now this is something only astronomers are really interested in. It's kind of sneaking under the radar of the public at large. They are going to get a big shock someday. When the first truly Earth-like planet is discovered, with unambiguous signs of a living biosphere (for example, lots of free oxygen in the atmosphere), the psychological impact will be huge.

      Actually, there was a recent National Geographic article that talked specifically about looking for Earth-like planets orbiting around nearby sta
  • But does it run Linux?
  • For those of us who aren't American, just how big is a "football-field size"? (Yes, I can Google for it, but for fuck's sake, you might crash fewer space probes if you used "metres" instead of "football fields" as a unit of measure. Just a thought.)

  • If you have tried to read any of the derivations for the image at the focus of an interferometer, it reduces to a Fourier transform.

    For a quick "hack", you can see what a point-source looks like if you just use the (2 dimensional) FFT, with two circles separated the right distance as input. (with appropriate sampling, oversampling, etc)

    I find this way of looking at it quite elegant, not to mention the ease in writing the simulation code (barely any). In other words, the interferometer setup is equivale

  • Couldn't they have come up with a better name?

  • That's pretty impressive... (Score:1, Insightful)

    by Anonymous Coward
    ... until you realize that it takes about 10,000x greater reduction in light from the parent star to actually spot Earth sized planets in other Solar Systems. It's a good first step, but they have a long way to go.
  • Besides the obvious 10 year delay mandated by government beaurocracy, they seemed to be running that thing since 2000 without the interferometer. It's hard to believe it took so long to get just one image from the interferometer. Not even going to bother finding the actual image on the internet.

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