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Space Science

Largest Lens Ever Discovered 198

Posted by timothy from the new-prescription dept.
K Tanmay writes "A team of Astronomers have found a natural lens capable of resolving details as fine as 10 microarcseconds across - equivalent to seeing a sugar cube on the Moon, from Earth. The lens comprises of a cloud of interstellar gas, and works on the principle of scintillation; where the clumpiness inside a cloud of gas creates a density change thus bending and focusing the light. This technique, dubbed 'Earth-Orbit Synthesis', will be first used to study black holes in distant quasars, so don't expect spectacular wallpaper replacing images. There's also an interview with Dr. Hayley Bignall, an astronomer from the Joint Institute for Very Long Baseline Interferometry in Europe (JIVE), where she discusses the concept of using interstellar scintillation to get observations that we could never measure from here on earth." Update: 02/22 18:23 GMT by T : That wikipedia link had led to the wrong place; here's the definition for arcsecond if you still want to read it.
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Largest Lens Ever Discovered More

Largest Lens Ever Discovered

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  • Actually... (Score:2, Interesting)

    by Anonymous Coward
    What is a quasar? I've never really had a satisfactory explanation for this.

  • This is so amazing! (Score:5, Funny)

    by digital_milo ( 212475 ) on Sunday February 22, 2004 @01:13PM (#8356369)
    They've found sugar on the MOON!!!

  • Uhm... (Score:5, Interesting)

    by Black Parrot ( 19622 ) on Sunday February 22, 2004 @01:16PM (#8356391)


    Maybe we need a new method for determining the distance between "scintillation" [wikipedia.org] and "arcsecond".

  • So... (Score:5, Funny)

    by hookedup ( 630460 ) on Sunday February 22, 2004 @01:16PM (#8356396)
    Does this mean we can finally see the so called "landing site" on the moon? :)

    • Re:So... (Score:5, Funny)

      by Lost Dragon ( 632401 ) on Sunday February 22, 2004 @01:19PM (#8356411)
      Not unless there's a gas cloud between here and the moon. Chances are good the one hovering over L.A. doesn't count.

    • Re:So... (Score:5, Funny)

      by kfg ( 145172 ) on Sunday February 22, 2004 @01:28PM (#8356473)
      Man, are you behind the times. The Moon is a hoax, in and of itself. That's why it was so easy to fake landing on it.

      Moon me baby [revisionism.nl]

      KFG

      • The "Moon": A Ridiculous Liberal Myth (Score:5, Funny)

        by AEton ( 654737 ) on Sunday February 22, 2004 @02:58PM (#8356919)
        Right on, brother. Slashdot herself has offered proof of this hypothesis.

        It amazes me that so many allegedly "educated" people have fallen so quickly and so hard for a fraudulent fabrication of such laughable proportions. The very idea that a gigantic ball of rock happens to orbit our planet, showing itself in neat, four-week cycles -- with the same side facing us all the time -- is ludicrous. Furthermore, it is an insult to common sense and a damnable affront to intellectual honesty and integrity. That people actually believe it is evidence that the liberals have wrested the last vestiges of control of our public school system from decent, God-fearing Americans (as if any further evidence was needed! Daddy's Roommate? God Almighty!)

        Documentaries such as Enemy of the State [imdb.com] have accurately portrayed the elaborate, byzantine network of surveillance satellites that the liberals have sent into space to spy on law-abiding Americans. Equipped with technology developed by Handgun Control, Inc., these satellites have the ability to detect firearms from hundreds of kilometers up. That's right, neighbors .. the next time you're out in the backyard exercising your Second Amendment rights, the liberals will see it! These satellites are sensitive enough to tell the difference between a Colt .45 and a .38 Special! And when they detect you with a firearm, their computers cross-reference the address to figure out your name, and then an enormous database housed at Berkeley is updated with information about you.

        Of course, this all works fine during the day, but what about at night? Even the liberals can't control the rotation of the Earth to prevent nightfall from setting in (only Joshua was able to ask for that particular favor!) That's where the "moon" comes in. Powered by nuclear reactors, the "moon" is nothing more than an enormous balloon, emitting trillions of candlepower of gun-revealing light. Piloted by key members of the liberal community, the "moon" is strategically moved across the country, pointing out those who dare to make use of their God-given rights at night!

        Yes, I know this probably sounds paranoid and preposterous, but consider this. Despite what the revisionist historians tell you, there is no mention of the "moon" anywhere in literature or historical documents -- anywhere -- before 1950. That is when it was initially launched. When President Josef Kennedy, at the State of the Union address, proclaimed "We choose to go to the moon", he may as well have said "We choose to go to the weather balloon." The subsequent faking of a "moon" landing on national TV was the first step in a long history of the erosion of our constitutional rights by leftists in this country. No longer can we hide from our government when the sun goes down.

        • Re: "The Moon": A Ridiculous Liberal Myth (Score:1, Funny)

          by Anonymous Coward

          I simply refuse to put up with limp, Satanic, fellow-travelling shit like this piece of sub-human garbage in your pewling, idiotic post:

          "Even the liberals can't control the rotation of the Earth to prevent nightfall from setting in (only Joshua was able to ask for that particular favor!) "

          Let's count the errors, shall we?

          1. The Earth does not "rotate". If it did, we would all be blown around ten ways to Tuesday by the winds created.

          2. If the Earth did rotate, then one would expect to see tornadoes

        • These satellites are sensitive enough to tell the difference between a Colt .45 and a .38 Special!

          Do you mean a revolver firing .45 Colt or a Colt Model 1911 semi-auto pistol firing .45 ACP? And what about .38 super? I have a 1911 that's chambered in .38 Super. Would that confuse those fascist liberals?
      • "You can do this, too, Neo. You only have to realize that in fact, there is no Moon".

    • Re:So... (Score:1, Insightful)

      by Anonymous Coward
      Lunar landing conspiracy nonsense aside, I should think the answer is no.

      You usually have the lens between you (the observer) and the thing being observed. That is, you have to be looking at light (or whatever part of the EM spectrum they're observing) that has come from the target, gone through the lens, and is heading towards Terra.

      In short, since there isn't one of these incredibly large gas clouds between Terra and Luna, no, I really don't think we can use it to look at the moon.
    • "Does this mean we can finally see the so called "landing site" on the moon? :) "

      Sure! We just need to send a telescope to the other side of the cloud.

  • Why Put Sugar on the Moon? (Score:5, Funny)

    by servoled ( 174239 ) on Sunday February 22, 2004 @01:16PM (#8356397)
    Jeez... everyone knows that cheese and sugar have no business going together. Put a piece of sausage up there and you might have something worth looking at.

  • Apollo (Score:2, Interesting)

    by $calar ( 590356 )
    Alright! Now we can see the stuff we left on the moon to prove to all of those skeptics. Seriously though, I was just reading about this a couple of weeks ago and they said that no current telescope technology can resolve objects as small as the lunar rover on the moon from earth.

  • Better name?? (Score:5, Funny)

    by John Seminal ( 698722 ) on Sunday February 22, 2004 @01:18PM (#8356410) Journal
    There's also an interview with Dr. Hayley Bignall, an astronomer from the Joint Institute for Very Long Baseline Interferometry in Europe (JIVE), where he discusses the concept of using interstellar scintillation to get observations that we could never measure from here on earth

    Jive? Who's running the place? The gang from What's Happening? Is Sherly still fighting with Rerun?

    Names mean something. If you look at legislation in the USA, they often try and make laws look like the opposite of what they are, like the patriot act, which takes away civil liberties. So if they want to have the name Jive, they will probably not get the same respect as if they were called Astronomy Scholarly Studies.

  • Dyn-o-mite (Score:5, Funny)

    by grungebox ( 578982 ) on Sunday February 22, 2004 @01:19PM (#8356413) Homepage
    The astronomer is from a group called JIVE? That's whack, yo.

  • and they join forces... (Score:5, Funny)

    by SuperBanana ( 662181 ) on Sunday February 22, 2004 @01:20PM (#8356421)
    have found a natural lens

    Fantastic! Now the alien people and the tin foil hat wearers can join forces- because not only is their life elsewhere in the universe, by golly, they're SPYING on us! Quick, someone phone Barbara Streisand so she can sue them for photographing her back yard.

    There's something in this for everyone, really- even the people who think the rovers are getting sabotaged. After all, when you're a futuristic-technology-wielding, hip happenin' intergalactic alien...hmm, what's the saying? Oh yeah. When you've got a gas-giant lens, the whole universe looks like an ant in need of frying.

  • IANAA (Score:4, Informative)

    by 3ryon ( 415000 ) on Sunday February 22, 2004 @01:22PM (#8356430)
    I am not an astrophysist, but does the phrase, "will be first used to study black holes in distant quasars" have any meaning at all?

    • Re:IANAA (Score:5, Informative)

      by Abcd1234 ( 188840 ) on Sunday February 22, 2004 @01:38PM (#8356520) Homepage
      Umm... yes. Supermassive blackholes are the leading candidates for the engines driving quasars. From Google:

      "Quasar - an enormously bright object at the edge of our Universe that emits massive amounts of energy. In an optical telescope, they appear point-like, similar to stars, from which they derive their name. Their high luminosity is created from matter falling into a supermassive black hole in the centers of distant galaxies."

    • Re:IANAA (Score:3, Interesting)

      by philbert26 ( 705644 )
      I am not an astrophysist, but does the phrase, "will be first used to study black holes in distant quasars" have any meaning at all? Working from memory of my astrophysics classes...

      Quasars are bright objects that are much larger than stars (a few light-days across) and are observed in the distant universe (that is to say, they existed in the distant past and the light from them is just reaching us now).

      There is a theory that the quasars are a type of active galactic nucleus, powered by black holes. Ma

    • Yeah, I also pictured a line of astrophysicists waiting for their "turn" to use the lens... "Hey, hurry up, will ya? You think you could give someone else a turn?"

  • Oddly Enough (Score:5, Funny)

    by kurosawdust ( 654754 ) on Sunday February 22, 2004 @01:24PM (#8356447)
    In other news, the lens was found approximately three miles away from a giant on all fours combing the ground with his hands.

  • but... (Score:4, Interesting)

    by UnMutedChaos ( 722557 ) on Sunday February 22, 2004 @01:24PM (#8356451)
    If we can't see a sugar cude on the moon right now, so how can we tell how this lens is focusing if at all? A few small defects in hubbles lens blured it bad, some thing this big would have alot of area for defects. to me that seams like it would make a very bad lens. So my real question is? how is this usefull?

    • Re:but... (Score:5, Interesting)

      by jafiwam ( 310805 ) on Sunday February 22, 2004 @02:40PM (#8356822) Homepage Journal
      Hubble is used to generate images where quality is measured by pixels per area of the target, and making sure all the pixels are faithfully in the correct place on the image.

      There are lots of other types of information that can be gathered; a full spectrum and spectral lines, shifted or not. Pulsing or changes in the amount of light, and so on.

      So this type of lens extends the reach of devices that gather non-image type data by gathering light from a WIDE area and allowing us to pick it up on earth.

      So think of it as a really really huge radio dish, not as a big hunk of glass.
    • "If we can't see a sugar cude on the moon right now, so how can we tell how this lens is focusing if at all?"

      Because with it they found an inscription reading "If you can read this, you don't need glasses".

  • An error in the illustration? (Score:5, Interesting)

    by beeplet ( 735701 ) <beeplet@gmail.com> on Sunday February 22, 2004 @01:25PM (#8356457) Journal
    The caption to one of the illustrations reads:

    At some times of the year, both the Earth and the cloud 'lens' are moving in the same direction, and the observed variations are slow, but six months later they are moving in opposite directions and the variations are fast.

    while the illustrations clearly shows a a wave which is of constant frequency but of varying amplitude. I believe the caption is correct...

    And a related complaint: what is the point of including a picture of the ring nebula with the caption:

    The Ring Nebula, although not useful imaging through, has the suggestive look of a far-away telescope lens.

    I guess when you can't come up with any images actually related to the topic, you might as well throw in some pretty Hubble pictures for those who aren't going to read the text anyway.

  • wallpaper? (Score:5, Insightful)

    by evilWurst ( 96042 ) on Sunday February 22, 2004 @01:25PM (#8356458) Journal
    "This technique, dubbed 'Earth-Orbit Synthesis', will be first used to study black holes in distant quasars, so don't expect spectacular wallpaper replacing images. "

    Two words: Accretion disc.

    Black holes themselves may be, well, *black*, but all the stuff swirling into them and/or being ejected from the poles glows nicely. And if that's the sort of thing making the quasar so bright, the images should be spectacular indeed. (note: it'll be a false-color image)

  • Very Large Array (Score:5, Informative)

    by FTL ( 112112 ) * <slashdot&neil,fraser,name> on Sunday February 22, 2004 @01:27PM (#8356467) Homepage
    Check out the telescope array [nrao.edu] they used to find this lens. I don't know what's more impressive, the sheer size or the fact that each of the dishes are mobile and shift up and down the tracks so that the array can reconfigure itself for different types of observations.

    I remember seeing a photo of this array as a child. Back then it only had five dishes. I had no idea that it had been filled out. Why don't we hear about this sort of thing?

    • Re:Very Large Array (Score:5, Informative)

      by Chordonblue ( 585047 ) on Sunday February 22, 2004 @01:58PM (#8356620) Journal
      Hmmm.. You get to see some GREAT views of it in action in 'Contact'! :)

    • Re:Very Large Array (Score:5, Funny)

      by Sevn ( 12012 ) on Sunday February 22, 2004 @02:12PM (#8356684) Homepage Journal
      I remember seeing a photo of this array as a child. Back then it only had five dishes. I had no idea that it had been filled out.

      You'll find this happens as telescope arrays approach puberty. The once flat areas become curvy and full. Sweat glands start up production in earnest requiring a discussion about the importance of deodorant. Pretty soon your array will want a training bra requiring a trip to the mall.

    • Re:Very Large Array (Score:5, Funny)

      by niew ( 133188 ) on Sunday February 22, 2004 @03:45PM (#8357139)
      Hey you, second from the far right, [nrao.edu] Get with the programme!

    • Re:Very Large Array (Score:5, Informative)

      by RobertFisher ( 21116 ) on Sunday February 22, 2004 @04:25PM (#8357325) Journal
      Actually, the VLA has pretty much been in its current configuration for almost 25 years : see this historical note [nrao.edu] for some of its amazing history. The reason why you probably saw only five dishes is that the array can be operated in different modes. Depending on whether an astronomer wants a highly zoomed-in, extremely high-resolution image, or a wider field of view with lower resolution, he can instruct the telescope operators to move the array dishes either closer or father (respectively) on their tracks. Its one of the most basic tricks of radio interferometry. Sometimes even a single dish is used to repeat an observation of a highly resolved region at the same frequency; although the single dish cannot match the resolution of the array, it _can_ detect the total power emitted, and therefore determine how much the high-resolution observation "missed".

      You're absolutely right that we don't hear as much about radio astronomonical observations. There are probably a few reasons. The first stems from the fact that astronomers tend to specialize in a given waveband -- the knowledge and expertise that is required to observe in the optical is very different from that required to observe in the radio, and both are in turn radically different from that required to observe in gamma rays. A few exceptionally talented astronomers operate in a couple of bands, but almost none operate across the entire spectrum. Radio astronomers are a minority within the astronomical community, and while they do really great science, it is primarily on sources filled with cold gas or electrons gyrating in the magnetic field, and are somewhat more difficult to popularize than a snazzy Hubble photo. The other reason, I think, is largely cultural and political. NASA does a great job pushing its science (Hubble, Chandra, Spitzer, planetary missions) to the public's attention, and devotes a lot of its effort culling the media's attention. The remainder of the astronomical community, including the national radio and optical observatories, tends to be much more conservative, and does not make much of an effort to garner attention. Generally you will only hear of their work when the press appears at one of the American Astronomical Soceity (AAS) and snatches up a few of their stories to splash up in their papers and broadcasts.

      This parent posting was really great, and I applaud the moderators who modded it up. However, sadly, it was the ONLY reasonable post modded at 5 -- the rest are just a bunch of idiots making stupid comments which some other idiot found funny. Posters and moderators should definitely try harder to keep postings on topic and technically worthy. That is, after all, what slashdot is all about.

      Bob

  • Great discovery (Score:2, Interesting)

    by ahh ( 755373 )
    ... wonder how long it takes to figure how to combine array of these to create virtual super-scope ( like DARWIN) [tuwien.ac.at] and start watchin' exoplanets.

  • Black Holes in Distant Quasars (Score:4, Interesting)

    by whig ( 6869 ) * on Sunday February 22, 2004 @01:42PM (#8356538) Homepage Journal
    It will be interesting to see whether such phenomena are actually found.

    Some scientists have theorized that quasars are *not* distant galaxies, but stars with a peculiar lens-effect that causes a very large perceived red shift.

    Part of the problem with the idea that the red shift is a doppler effect is that the observed quasars are apparently all in a relatively spherical arrangement about the Earth, thus implying that the Earth must be the center of the observed universe.

    It could be that this is just an artifact of observation: we see the quasars as equidistant from Earth because we are perceiving them from Earth. But it is very strange and implies a problem with the theory.

    A paper [achilles.net] on this subject is available.

    • Re:Black Holes in Distant Quasars (Score:5, Informative)

      by beeplet ( 735701 ) <beeplet@gmail.com> on Sunday February 22, 2004 @01:55PM (#8356599) Journal
      Part of the problem with the idea that the red shift is a doppler effect is that the observed quasars are apparently all in a relatively spherical arrangement about the Earth, thus implying that the Earth must be the center of the observed universe

      Nonsense. The observed quasars appear isotropic for the same reason the cosmic microwave background is isotropic: we are looking back at a fairly homogeneous early universe. It is more reasonable to infer that quasars appear roughly equidistant because they were common during some point in the evolution of the universe; it is the separation in time, not distance, that matters.

    • Re: Black Holes in Distant Quasars (Score:5, Insightful)

      by Black Parrot ( 19622 ) on Sunday February 22, 2004 @01:58PM (#8356622)


      > Part of the problem with the idea that the red shift is a doppler effect is that the observed quasars are apparently all in a relatively spherical arrangement about the Earth, thus implying that the Earth must be the center of the observed universe.

      The earth is at the center of the observable universe, pretty much by definition.

      Unless of course the observer in question isn't on the earth.

      • The earth is at the center of the observable universe, pretty much by definition. Unless of course the observer in question isn't on the earth.

        Good point.

        Of course, the problem of the "what constitutes the observable universe?" is easily resolved by smartly knocking the observer upside the head with a telescope.

        -kgj
    • Part of the problem with the idea that the red shift is a doppler effect is that the observed quasars are apparently all in a relatively spherical arrangement about the Earth, thus implying that the Earth must be the center of the observed universe.

      ***Gasp*** What do you mean? it isn't??? I thought Copernicus had destroyed that theory!

    • Re:Black Holes in Distant Quasars (Score:2, Informative)

      by Anonymous Coward
      They appear roughly equidistant from the Earth, it is thought, because they were all in existence at roughly the same time. Remember that distance (on the intergalactic scale) equates to age, so that objects which lie a certain distance away appear to us as they actually were during a particular common epoch, not as they are now.

  • Whoa... (Score:4, Funny)

    by Raynach ( 713366 ) on Sunday February 22, 2004 @01:43PM (#8356543) Homepage
    You'd have to be some kind of supreme nerd to require a lens of THAT prescription.

  • Wikipedia... (Score:5, Funny)

    by pediddle ( 592795 ) <pediddle+slashdo ... ATSet minus poet> on Sunday February 22, 2004 @01:45PM (#8356549) Homepage
    Definition of an Arcsecond: "Quit portscanning me."

    I guess they don't slike being slashdotted?
  • So is this "The Largest Lens, Ever Discovered" or "The Largest Lens Ever, Discovered"?

  • Let's Crush Wikipedia (Score:4, Funny)

    by SparafucileMan ( 544171 ) on Sunday February 22, 2004 @01:55PM (#8356600)
    Uh, isn't Wikipedia suffering enough [slashdot.org] from overuse and underfunding of it's bandwidth/serverload...I mean seriously, can't you editors find another site to use as a dictionary?

    • Re:Let's Crush Wikipedia (Score:1, Informative)

      by Anonymous Coward
      Wikipedia is fine at the moment.

      Last time there were server problems, a few of the servers had exploded, one of the servers arrived pre-exploded, and the rest had been ordered but were still in the mail.

      The funding problem could theoretically have been solved earlier, using a time machine [wikipedia.org], however that was not accomplished due to technical difficulties.

      Wikipedia [wikipedia.org] is an encyclopaedia, not a dictionary. The dictionary is called Wiktionary [wikipedia.org].

      (Approximate quote from Wikipedia developer: Average response ti

    • WHat? You mean like this online dictionary [reference.com]?
  • Definition links on Slashdot went to Everything2, not Wikipedia.

    Normally there's a little ? next to the word which links to E2.
  • [pet peeve]
    Oh, I apologize in advance for this, but K Tanmay has been busted by the Grammar Police for the following:

    The lens comprises of a cloud of interstellar gas, and works on the principle of scintillation; where the clumpiness inside a cloud of gas creates a density change thus bending and focusing the light.

    Semicolons are used for separating independent clauses, not dependent ones. Use a comma instead.

    Again, sorry. This is just my...
    [/pet peeve]

    • Re:Grammar is _never_ offtopic. (Score:3, Funny)

      by Anonymous Coward
      At the risk of being inscansipitory.

      That is an independant clause.

      "The clumpiness inside a cloud of gas creates a density change thus bending and focusing the light." is a complete sentence, perhaps not a very good one....

      "Where" in this case is used to more closely connect the two ideas. In a manner not too dissimilar from "; however,". You were right, there is a comma missing. You were also mostly wrong. The semicolon is proper in this case, and you misidentified a clause.

      So for failing grammer n

  • Not the "Largest Lens Ever Discovered" (Score:4, Informative)

    by barakn ( 641218 ) on Sunday February 22, 2004 @02:18PM (#8356710)
    Entire galaxy clusters perform gravitational lensing [utk.edu]. Galaxy clusters, in terms of mass and size, are vastly larger than these gas clouds, which are either a million kilometers away or wide, depending on how you interpret this poorly worded sentence:

    The length of a telescope needed to peer into the mouth of the blazar would have to be gigantic, about a million kilometers wide.

  • Imagine... (Score:5, Funny)

    by mav[LAG] ( 31387 ) on Sunday February 22, 2004 @02:24PM (#8356740)
    ...a globular cluster of these!

  • This just in... (Score:3, Funny)

    by Frennzy ( 730093 ) on Sunday February 22, 2004 @02:27PM (#8356760) Homepage
    The giant, intergalactic being wearing the lense has been identified as one 'Hans Moleman'...

  • Quote:
    Slashdot PWNED

    It's good to see the maturity of the average slashdotter showing up in the wiki.

  • uhm... (Score:5, Informative)

    by Hegestratos ( 66481 ) on Sunday February 22, 2004 @03:24PM (#8357043)
    There's also an interview with Dr. Hayley Bignall, [...], where he discusses [...].

    He? I know astrophysicist is a male-dominated profession. But a name like 'Hayley' should at the very least make one wonder. See this page [www.jive.nl] to accurately determine Dr. Bignall's gender.

    Furthermore, this is nothing really new; see this /. story [slashdot.org], amongst others.

    Still, it's a very creative way of increasing resolution! Not to mention difficult and time-consuming. I wonder how believable the results are. I use a similar technique (called Speckle Masking) to eliminate earth-atmosphere scintillation from Solar observations, with astounding results. These, however, can be checked against single 'lucky shot' images of extrodinary quality or observations from space...

    Cheers,

    Alfred
  • > A team of Astronomers have found a natural lens capable of resolving details as fine as 10 microarcseconds across ...
    here's the definition for arcsecond [wikipedia.org] if you still want to read it.

    After following one link from above page (to this page [wikipedia.org]), we get:
    In astronomy, one can measure the angular separation of two stars by imagining two lines through the Earth, each one intersecting one of the stars. Then the angle between those lines can be measured; this is the angular separation between the two stars.

    • Re:Oh, Galileo! (Score:3, Insightful)

      by Rallion ( 711805 )
      Erm, angular seperation is useless unless you know it based on the place that you're looking from, really. What good does it do to know how far apart two stars appear to be looking from the center of the universe?

  • Pulsars can do as good or better than this... (Score:5, Interesting)

    by Scott Ransom ( 6419 ) <sransom AT nrao DOT edu> on Sunday February 22, 2004 @04:31PM (#8357370)
    High precision timing of millisecond pulsars (which accounts for every single rotation of a pulsar over the course of several years) can make observations with astrometric (i.e. positional) errors of several micro arcseconds.

    An excellent example was published in Nature in 2001. Here is a preprint [lanl.gov]. The work describes the timing of the nearby (~450 lt-yrs) millisecond pulsar J0437-4715. The proper motion (movement across the sky) and parallax (apparent motion on the sky due to the earth's orbit) of the pulsar were measured to extreme precision, and a new test of General Relativity was also given.

    PS: IAAPA (I am a pulsar astronomer)

  • Lens diameter (Score:2, Insightful)

    by JonCol79 ( 520193 )
    So according to Rayleigh's formula, that kind of resolution would mean that the lens diameter would be about 13 km (for visible light having a wavelength of 500 nm). Of course, with a lens that big one would have serious aberration problems. (First-year-physics-student syndrome made me do it.)

  • The final proof (Score:3, Funny)

    by Barkmullz ( 594479 ) on Sunday February 22, 2004 @04:35PM (#8357399)

    The argument goes something like this: "I refuse to prove that I exist," says God, "for proof denies faith, and without faith I am nothing."
    "But," says Man, "the Babel fish is a dead giveaway isn't it? It could not have evolved by chance. It proves you exist, and therefore, by your own arguments, you don't. QED."
    "Oh dear," says God, "I hadn't thought of that," and promptly vanishes in a puff of logic.
    "Oh, that was easy," says Man, and for an encore goes on to prove that black is white and gets killed on the next zebra crossing.

    Replace Babel fish with natural lens capable of resolving details as fine as 10 microarcseconds across

  • See this [slashdot.org] for the original Slashdot story. The press release [csiro.au] is at the Australia Telescope National Facility website.

  • lenses, resolution and radio (and Carl Sagan!) (Score:5, Interesting)

    by sdedeo ( 683762 ) on Sunday February 22, 2004 @05:17PM (#8357595) Homepage Journal
    Interstellar scintillation is really neat and interesting. You can use its properties to measure the nature of the interstellar medium indirectly -- for example, from the dispersion of a pulsar signal (a pulsar emits something a little like a square wave pulse in the radio, which is then smudged and smeared out as different wavelengths scintillate differently.)

    I studied I.S. a little bit awhile back. Carl Sagan did some work on scintillation; the scintillation effect can pull out a distant radio signal by gathering in rays from a lot of different directions and accidentally throwing them right at you. The famous WOW [seds.org] signal, I believe, was investigated as an example of scintillation from a big cloud much like the ones described in the article.

    It is interesting to see this technique used to do radio astronomy. Most of the times when you encounter a natural lens, it is sufficiently weird that you use the observation to analyse the lens itself, and not what it happens to be magnifying. Gravitational lenses are interesting in large part because you can try to figure out the distribution of dark matter in the lens itself -- and not because you can use it to "see into" the object being lensed. These lenses are not exactly perfect optics -- they're more like balls of glass, which distort and differentially magnify something behind.

    But I'm not as familiar any more with radio astronomy. It is definitely possible that we understand enough about the properties of the ISM that the more interesting problem of figuring out the properties of the background object is open for work. Very cool!

  • To use a Farkism... (Score:3)

    by SIGBUS ( 8236 ) on Sunday February 22, 2004 @05:57PM (#8357816) Homepage
    ...Canon surrenders.

  • Unblobbing a blob? (Score:2, Interesting)

    by Tablizer ( 95088 )
    I don't really get how they put the image(s) back together. The clouds are not perfectly round and it is like observing one point at a time at best, and hard to know what point it is because the "lens" changes what it is looking at. I suppose the motion of the cloud and earth through space will give a "scan-line" like sample, but it would still almost be like trying to figure out what the sun looks like by studying the sparkley net-like wavey patterns at the bottom of a swimming pool.
  • so that explains the chinese entry into the space-race.

  • Observe our own history (Score:1, Funny)

    by Anonymous Coward
    All we need now is to find a large reflecting object at a distance of a 1000 light years and we can observe our own history while looking through this telescope and see if the Romans had invented sugar cubes before us. Its time we got some concrete observations about what the Romans did for us.

  • In other news, (Score:3, Funny)

    by mbstone ( 457308 ) on Monday February 23, 2004 @01:01AM (#8360102)
    SPECTRE has announced that Ernst Stavro Blofeld has successfully aligned the interstellar-gas lens with the stellar diamond and it is now focused at major population centers on Earth. World governments are attempting to come up with the ransom. More at 11.......

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