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Space Science

Jill Tarter and the Allen Telescope Array 147

Posted by Hemos from the looking-to-the-skies dept.
An anonymous reader writes "Today's interview with Jill Tarter of the SETI Institute (and Carl Sagan's inspiration for the main character of his novel Contact), outlines the forthcoming search capabilities of the large Allen Telescope Array. Their thousand-fold expanded search must find promising places to point 350 radio dishes. Outside San Francisco, the array spans an equivalent 8 football fields. Their new catalog, called HabCat, identifies all potentially habitable hosts for complex life within 450 light-years from Earth. Of the billions of places to point in the sky, their A-list total: 17,129. Start at Vega."
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Jill Tarter and the Allen Telescope Array More

Jill Tarter and the Allen Telescope Array

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  • Oh no! (Score:1, Funny)

    by richie2000 ( 159732 )
    Imagine our embarrassment when They finally arrive and want to be taken to our leader and we realize we have to let them meet George W. It's going to be Mars Attacks all over again...

  • Allen Telescope Array (Score:3, Funny)

    by Anonymous Coward on Monday April 21, 2003 @09:44AM (#5772827)
    hehehe... I just read it as "Alien Transport Array".

    Damn... Too much coffee....
  • Is this proof that not everything that comes out of Microsoft is evil, or is it just a way to expand the market for Windows? :-)
  • Why would we want to catalog habitable places within 450 light years, when our current space exploration can't get past our moon!?

    Also, can anyone explain the difference between a parsec and a light year???? I know its something about the arcsecond of the something and the whatchamagigger but yeah, thats about that...
    • 1 parsec = 3.26 light years

    • Re:Whats with the measurements?? (Score:5, Informative)

      by richie2000 ( 159732 ) <rickard.olsson@gmail.com> on Monday April 21, 2003 @09:53AM (#5772880) Homepage Journal
      Easy. A light year is like a leap year, except we set it on fire to light up the place a bit. A parsec [parsec.org] is a fast-paced multiplayer cross-platform 3D Internet space combat game.

      Or, it could be that a light year [uottawa.ca] is the distance that a photon would travel on a standard solar year, in vacuum, while a parsec [uottawa.ca] is the distance from which the radius of the earth's orbit would subtend an angle of one second of arc. One parsec is roughly 3.26168 light years.

      Google is mother, Google is father. Worship Google.

      • "subtend" escaped my high-school geometry education. At first glance, it could mean serving small candy submarines at a party. However, m-w.com, crushed my imagination:

        Main Entry: subtend ... 1 a : to be opposite to and extend from one side to the other of <a hypotenuse subtends a right angle> b : to fix the angular extent of with respect to a fixed point or object taken as the vertex <the angle subtended at the eye by an object of given width and a fixed distance away> <a central angle su
      • Well I must have one lame internet connection, because I can't get those Canadian web sites to work.

        I much perfer Eric's [wolfram.com] definitions of Light Year [wolfram.com] and Parsec [wolfram.com].
    • One Parsec = 3.26 Light Years.

      More technically, One parsec is the distance at which one astronomical unit subtends one second of arc.

      See: This Site [uottawa.ca] for a definition of the Parsec.
      See: This Site [uottawa.ca] for a definition of the Light Year
    • First off, we have gotten past our moon with our manless space exploration.

      Secondly, just because we discover a signal coming from a planet 450 light years away doesn't mean we have to go there. The knowledge contained in that signal would be enough to warrant such cataloging. If that civilization is anything like ours, they might think to broadcast an "encyclopedia galactica" like Brian McConnell suggests in his book Beyond Contact.
    • Especially considering we did find a habitable planet 450 light years away, and started travelling NOW, and travelled at the speed of light, we'd still arrive 450 years from now.

      Very dead, I suppose. Or we'd need to travel in families, reproduce and multiply enroute, and our great-great-great-great-great-great-grandchildren MIGHT make it! Wow... We first need to research extending life spans first.

  • Looking at the tools... (Score:3, Interesting)

    by WegianWarrior ( 649800 ) on Monday April 21, 2003 @09:48AM (#5772855) Journal

    ...a network of 350 radio antenna dishes. Called the Allen Telescope Array (or ATA), the network ties together 6.1 meter (~20 foot) diameter dishes for a total surface area as large as eight football fields.

    I thought that the baseline of a telescope array was more important than the collecting area - or is that just when you work in the visible wavelenghts? Can anyone set me straight on that?

    • Re:Looking at the tools... (Score:5, Informative)

      by vofka ( 572268 ) on Monday April 21, 2003 @10:20AM (#5773000) Journal
      Have a look at This Introduction [man.ac.uk] to Very Long Baseline Interferometry at the Jodrell Bank Obervatory website - that will tell you (almost) everything you ever wanted to know about VLBI, and then some!!
    • Each measure is important in its own way. Large baselines give you greater resolution, or the ability to distinguish between objects that are very close together. Collecting area gives you greater sensitivity, or the ability to image fainter and farther objects. These apply to all wavelengths, from the radio up through x-ray.
    • I thought that the baseline of a telescope array was more important than the collecting area - or is that just when you work in the visible wavelenghts?

      The baseline is more important if angular resolution is what you are after. If you just want to detect very faint signals, then you want the biggest collecting area that you can afford. In the case of SETI, angular resolution is not required, they just want to get the signal.

      The wavelength doesn't enter into it, other than the fact that interferometry i
    • Called the Allen Telescope Array (or ATA),

      We much prefer the Scientists Concerned with Space Intelligence (or SCSI) Array for serious work , even if it is a bit more expensive.

  • In some ways, the catalog is a waste of time. (Score:3, Interesting)

    by Anonymous Coward on Monday April 21, 2003 @09:49AM (#5772858)
    The guesses at inhabitable worlds sure fits in with assumptions of Trekkies. It assumes that other life on other planets would be humanlike and thus need a similar environment.

    The usefulness of looking for Earthlike worlds to find life is marginal at best: it is based on generalizations from a sample set of one. Yes, just one.

    I would guess that if we ever find "life" out there, it is going to be like nothing we expected in a place we never expected it. But that is just my guess, as after all we have no idea.
    • i think they plan on looking at more than just the planets on their A-list. it seems to me that they are looking for planets like our own first, then moving on to other possibilities.

    • Re:In some ways, the catalog is a waste of time. (Score:5, Funny)

      by drgroove ( 631550 ) on Monday April 21, 2003 @10:19AM (#5772997)
      The guesses at inhabitable worlds sure fits in with assumptions of Trekkies. It assumes that other life on other planets would be humanlike and thus need a similar environment.

      The only differences being that, while human like, the aliens have blue skin and green afros. Oh, and if we were to visit the surface of their world, the lowest-ranking member of the party would always be turned into a rock, or eaten by a giant alien squid, or killed in hand-to-hand combat with their greatest warrior.

    • What else would you suggest? (Score:5, Insightful)

      by robinw ( 257786 ) on Monday April 21, 2003 @10:31AM (#5773059) Homepage
      Actually, there are more assumptions made than that. They are assuming that the lifeforms have developed radio technology as a form of communication, which could also be seen as an evolution of the ears/mouth that we have.

      Really, though, what it comes down to is this - the universe is REALLY, REALLY, REALLY big. And the amount of time they have to scan it is REALLY, REALLY, REALLY small. So what they're doing is deciding which planets to scan first. Since we have no idea what other platforms that life could have evolved on, the safest bet is to use that short amount of time is to scan those which are similar to our own. The idea being that we DO know what kind of variables were able to sustain life here.

      In the future, I think you'll see they'll expand their searching, as technology improves and our understanding increases.
      • Radio waves do not necessarily suggest that vocal or audio information is the modulating waveform. In fact I believe the radio waves sent out in to space from earth (on purpose) are prime numbers and pictures, but what do I know, I get my info from the movies.

    • Re:In some ways, the catalog is a waste of time. (Score:5, Insightful)

      by Glock27 ( 446276 ) on Monday April 21, 2003 @10:43AM (#5773127)
      It assumes that other life on other planets would be humanlike and thus need a similar environment.

      There is more to it than that. Biochemists have done substantial analysis regarding what other chemical families might support life. It looks as though with the periodic table as it is, carbon is the only good choice for rich biochemistry. For carbon life to develop, liquid water appears necessary. So, you have narrowed the search volume considerably by only considering stars that would likely have a planet in the "liquid water" sweet spot, while not getting fried by hard radiation at the same time.

      Further, a planet must exist long enough for evolution to occur. That eliminates a great number of stars as well - many just don't last long enough.

      As another poster pointed out, that at least provides a starting point on where to look.

      • Biochemists have done substantial analysis regarding what other chemical families might support life.

        And in one implicit assumption (that all life must be based on the same kind of chemical interactions that we are) you have duplicated the mistake made by these SETI people.

        For all we know, the universe could be full of intelligent life based, not on chemical interactions, but on quantum interactions, or perhaps complex interactions of particles based on gravity, or perhaps some subtle physical effect w

        • And in one implicit assumption (that all life must be based on the same kind of chemical interactions that we are) you have duplicated the mistake made by these SETI people.

          It is by no means "must" - it is simply considered most likely. The scientists are going with the best probabilities based on, surprise, the science we know.

          For all we know, the universe could be full of intelligent life based, not on chemical interactions, but on quantum interactions, or perhaps complex interactions of particles ba

          • It is by no means "must" - it is simply considered most likely. The scientists are going with the best probabilities based on, surprise, the science we know.
            Er, the science we know tells us that you can't deduce anything from a sample size of 1, which is exactly what these people are doing.
            • you can't deduce anything from a sample size of 1, which is exactly which is exactly what these people are doing.

              No that is not "exactly what these people are doing", as has already been explained in some detail.

              The issue is broad physical/chemical/biological principles, not the exact track of life on Earth, per se.

        • or perhaps some subtle physical effect we don't even know about yet.

          If we don't know about it yet, it's unlikely that the effect will occur enough with a frequency or significance that life will evolve based on it.

          Likewise with your other points. These things are not noticable to ordinary matter, which makes it unlikely for these things to affect ordinary matter in such a way as to create life based on ordinary matter.

          It is possible that chemical-based life will evolve (probably deliberately) to some f

          • No offense to you personally, but I trust the biologists and astrophysicists with PhD's a little more about what types of life might be out there than most Slashdot couch scientists.

            Well, I have a degree in Artificial Intelligence and have done quite a bit of work in the area of Artificial Life - so I think that makes me more qualified than most "couch scientists". I would also be wary of the opinions of biologists, their definition of life is probably quite narrowly based on what they have observed on

    • The guesses at inhabitable worlds sure fits in with assumptions of Trekkies.

      They are not "assumptions". Aliens look like humans on Star Trek because they are portrayed by humans.

  • What does any one know about the Wow signal? Is it on the list? Has it ever been repeated? I met the guy who first heard that and the work they are doing is very interesting.

    • Re:Wow Signal. (Score:5, Informative)

      by richie2000 ( 159732 ) <rickard.olsson@gmail.com> on Monday April 21, 2003 @10:04AM (#5772929) Homepage Journal
      This [space.com] article was linked from the article in the post.

      Excerpt:

      In the October 20 issue of The Astrophysical Journal, Gray and Simon Ellingsen, of Australia's University of Tasmania, report on new observations (partially supported by the SETI Institute) designed to test this idea. Their new try was made at the 26-meter radio telescope in Hobart, Tasmania. This southern hemisphere instrument could continuously follow for most of a day the patch of sky (in the constellation of Sagittarius) where the "Big Ear" was pointing when it found the 'Wow' signal. They made six 14-hour observations, and even though their telescope was rather smaller than the venerable Ohio State antenna, they still had sufficient sensitivity to find signals only 5% as strong as Wow's 1977 intensity. They also covered five times as much of the radio dial as the original "Big Ear" telescope.

      Bottom line? No dice. To quote from their article, "no signals resembling the Ohio State Wow were detected..." Of course, if the signal's repetition cycle were much longer than 14 hours, then even this careful experiment could have easily missed it. But as Gray and Ellingsen point out, if the signal were really this infrequent, then the chance to have found it in the first place was very slim.

      So was the Wow signal our first detection of extraterrestrials? It might have been, but no scientist would make such a claim. Scientific experiment is inherently, and rightly, skeptical. This isn't just a sour attitude; it's the only way to avoid routinely fooling yourself. So until and unless the cosmic beep measured in Ohio is found again, the Wow signal will remain a What signal.

    • huh, what Wow signal. i want to hear it. is it anything like those annoying wow gossiple compilation cd's? cause if it is, i don't want to hear it then.

  • Rights Violations? (Score:3, Funny)

    by blind_abraxas ( 446151 ) on Monday April 21, 2003 @09:53AM (#5772875)
    If someone discovers that there are rebroadcasts of 40's baseball games with encoded secret plans,
    will the DMCA sue the aliens for rights violations? Shut E.T. down, Napster-style?

    • So you're saying that since they used their digits to encode the plans, that makes them digitally encoded? Sounds reasonable to me. :-)
    • If someone discovers that there are rebroadcasts of 40's baseball games with encoded secret plans, will the DMCA sue the aliens for rights violations? Shut E.T. down, Napster-style?

      Well, MLB will probably sue; you know after every game, they always say something like "this game may not be broadcast without the written consent of the commissioner and MLB teams..."

      So the first contact will probably be some sort of extraterrestial fax requesting permission said...

    • I know you're kidding, but it sometimes doesn't seem too far off target.

      Did you know the MPAA has been using stealth lobbying efforts to pass laws at the state level to enact a Super DMCA [eff.org] which criminalizes the possession of "unlawful communication and access devices"?

  • Wouldn't it be much more likely that a society advanced enough to be detectable across the vast reaches of interstellar space would find humans based upon primitive radio frequency transmissions? We might be able to just kick back and hope for our sake they don't take any of those hitler or vietnam broadcasts too seriously...

    While the possibility of extra-terrestrial life is a fascinating one, aren't there a lot more equally fascinating yet infinitely more practical aspects of space exploration to spend tons of money on?

    • aren't there a lot more equally fascinating yet infinitely more practical aspects of space exploration to spend tons of money on?

      Yes there are, and we spend lots of money on those, too. What is your point? Are you merely unhappy with the way money is being apportioned among the various interests? Then why don't yopu study to become a space scientist so you can have some influence?

    • Not if, in that advanced society, the majority of people believed the way you do. They'd just kick back and wait for us to find them.

      Only, we'd be expecting the same of them.

      Besides, I'd much rather see "tons of money" (which is privately donated, by the by) spent on this than the way we recently spent seventy-five billion (let that rattle around in your head a bit: Seventy. Five. BILLION.) dollars in the Middle East.

  • Not the inspiration for Contact... (Score:4, Interesting)

    by DShard ( 159067 ) on Monday April 21, 2003 @09:56AM (#5772895)
    is what she said in an interview in discover magazine. I can't remember which month but it was some time recently. She said she had asked Carl about this and he said the inspiration was himself.

  • Allen Telescope Array? (Score:5, Funny)

    by deander2 ( 26173 ) <public@ k e r e d .org> on Monday April 21, 2003 @10:01AM (#5772907) Homepage

    Am I the only one who read that as "Alien Telescope Array"? :P

    I need more cafffeeeeeeennee...
    • Am I the only one who read that as "Alien Telescope Array"?

      no your not.
      I need more cafffeeeeeeennee...

      your not the only one who needs more of that...sweet nectar of life...
      sleeps not all its cracked up to be you know

  • Divine Intervention (Score:4, Insightful)

    by kevlar ( 13509 ) on Monday April 21, 2003 @10:18AM (#5772989)

    Would you consider yourself a determined believer that extra-terrestrials exist? If (for the sake of discussion) you were to determine that we were, without a doubt the only life in the Universe, how would that impact any religious beliefs you may hold?

    I personally believe that if we were to be the only life in the Universe that this would be divine intervention simply because of the statistics, would you agree?
    • Mod this up. You may not agree, but it IS an intelligent question to ask here.
    • I don't think that is a question that will ever truely be answered unless one of two things happens. 1) god appears to everyone on earth and says that we are the only ones in the universe or 2) an alien species makes contact with the entire planet.

      But, if I had to actually answer I would say for me it wouldn't change my beliefs unless example 1) above occured. Of course everyone reacts differently, so I suppose it would change some peoples outlook on the world.

      For me the question has always been, why do

    • Re:Divine Intervention (Score:4, Insightful)

      by CaffeineAddict2001 ( 518485 ) on Monday April 21, 2003 @11:38AM (#5773511)
      No, it just tells us the old way of calculating the probability of life is wrong.

      It's very unlikely that today I will run into 13 eskimo amputee clowns at McDonalds.

      But suppose I do, which is more likely:
      1) This is the work of god.
      or
      2) Eskimo amputee clowns arn't as rare as I had previously thought.

    • I personally believe that if we were to be the only life in the Universe that this would be divine intervention simply because of the statistics, would you agree?

      And Drakaea elastica must also be a work of God, because, statistically, it's unlikely that a flower would grow to be shaped and scented so similar to a female wasp that males attempt to mate witht he flower.

    • Yes, yes I would have to agree that if we were the only life in the Universe, that would make God as likely as the non-existance of life elsewhere is unlikely.

      Let me rephrase: if life existing elsewhere were 99.9% likely, but it didn't happen, then I would say there was a 99.9% chance that it was, indeed, a divine plan. No matter what the numbers, there would always be uncertainty.

      Now for the big however.

      However, how the heck could we (a) prove that no life exists anywhere in the Universe? It is a rath

  • Cool article, cool web page (Score:5, Interesting)

    by Omega1045 ( 584264 ) on Monday April 21, 2003 @10:28AM (#5773044)
    While I am a huge SETI fan, I immediately noticed the menu system at the top of the Astrobiology Magazine website. It gives the user of the site the ability to email the story, fax it, download it in Word, Acrobat or PalmDoc, or make it printer friendly. Among other options, it also will translate to Spanish, and read the article to you in MP3.

    A lot of work, I think kudos should be given to the web dev team that put this site together. Very cool site!

  • ATA search capabilities (Score:4, Funny)

    by Pop n' Fresh ( 411094 ) on Monday April 21, 2003 @10:41AM (#5773114)
    "Today's interview with Jill Tarter of the SETI Institute (and Carl Sagan's inspiration for the main character of his novel Contact), outlines the forthcoming search capabilities of the large Allen Telescope Array.

    It's going to take them forever using ATA, wouldn't SCSI be able to handle many more simultaneous searches?

  • Turn off that light! (Score:5, Informative)

    by paiute ( 550198 ) on Monday April 21, 2003 @10:53AM (#5773186)
    After the events of the last few months, I am not so sure I want to be visited by an alien civilization - which is sure to have radically different notions of what behavior is justifiable - and that is sure to have unimaginable military superiority - and upon whom we can make no demands but have to accept their definition and conditions of our relationship.

    • The silliest idea of them all is that alien civilizations would be a threat to us. Why? Because it assumes that technology advances only in peripheral areas, but not in the one that is most essential: thinking. True, our brains haven't changed much in the last few thousand years, but then again, our modern industrial civilization is barely two centuries old, our understanding of the human brain and our little spacefaring ability is much younger still. Now think about the technological demands for interstell
    • Don't worry, our robot overlords will make short work of them once The Second Renaissance [theanimatrix.com] has passed...

      ... while we remain blissfully unaware ...

  • Why do it? (Score:5, Interesting)

    by PineHall ( 206441 ) on Monday April 21, 2003 @10:53AM (#5773189)
    I find the fascination with Extra-Terrestrials quite interesting. Is there some need for us to seek for someone outside of ourselves? Has the search for God been replaced by the search for ET? Are we looking for a God replacement?

    The reason I bring this up is that there is a very remote chance that an ET signal will ever be found and an even more remote chance that we will be able to communicate with them (impossible in the foreseeable future). So why spend money when the odds are so very low? What is this fascination?
    • there is a very remote chance that an ET signal will ever be found


      Why? That's a claim that deserves a bit of support, rather than being tossed out like that, cold, naked, and alone.

    • Re:Why do it? (Score:3, Interesting)

      by sigep_ohio ( 115364 )
      why do billions of people around the world believe in God? and give lots of money to their churchs/mosques/sinagogs(sp?)? belief in something greater than themselves. it is a need that lots of people seem to have. no one wants to think that we are alone. so if not god, then ET is who you look for.

      it all boils down to thinking that humans are special, and why are we special. if you are in the God camp, then most likely you think humans are unique in all the universe. the ET camp says we are not uniqu

    • Re:Why do it? (Score:5, Interesting)

      by mysticgoat ( 582871 ) on Monday April 21, 2003 @12:17PM (#5773786) Homepage Journal

      I find the fascination with Extra-Terrestrials quite interesting. Is there some need for us to seek for someone outside of ourselves? Has the search for God been replaced by the search for ET? Are we looking for a God replacement?

      I can only answer for myself, of course:

      1. Not a need in my case, but a desire that is stronger than the urge to purchase lottery tickets. See below.
      2. No, I continue to seek the gods as well as having an interest in seeking ET sentience. Obtaining a positive answer for one would probably have an impact on how I do the other, but at this point I do not see them as related endeavors. Certainly not as mutually exclusive pursuits.
      3. No, I wouldn't regard any other form of carbon/water based life as being a god substitute. Nor do I regard SETI's activities to be some kind of replacement for spiritual explorations.

      The reason I bring this up is that there is a very remote chance that an ET signal will ever be found and an even more remote chance that we will be able to communicate with them (impossible in the foreseeable future). So why spend money when the odds are so very low? What is this fascination?

      Agreed: the chances of SETI's success are very small. And the chance of finding that signal would be even more remote if nobody looks for it.

      As you suggest, the meat of the issue is a budgetary problem. If SETI is successful, reception of that first message would have as much impact on science, art, and religion as the Copernican revolution. It would be like winning the lottery, but bigger. So how cheap does the lottery ticket need to be before it makes sense to buy one every month? I think SETI is cheap enough to budget for.

      But SETI is unlike the lottery in one important way: if signals are not found in a reasonable length of time, that will tell me something useful. For instance, if the NASA Manned Mars Mission Proposal includes US$1 billion to develop a death ray to deal with inimical aliens, I would use SETI's negative findings to argue against such a pork barrel.

    • Fascination for potential knowledge, I guess. even if we would ever make 'contact,' chances are quite astronomical (yea,...) that we won't be able to interpret the 'message,' but only the fact that there is something out there would be of enourmous importance, it would, at least be a basis for new theories about the emergence of (intelligent) life. I do not agree this is a God replacement, God is supposed to have created the universe (in most religions, i think...) while E.T.'s are merely creatures of that
    • One benefit I see of discovering other intellignce in the universe is perhaps it will improve our solidarity as a species.

      It seems to be human nature to group ourselves as "us" versus "them". I think if "we" see "them" as another group separate from ourselves, then perhaps "we" (as a species) will get along a little better with each other than we are now.
      • but maybe it will also divide us even further. Governments could clamour for weapons in order to "protect" its citizens. Fights among religions could break out as people try to deal with the ramifications of thousands of years of beliefs that were not wholly true.
        While I would like to believe that it would bring us together as a planet. I think on a basic level humans are both social creatures and selfish. We barely seem to be able to strike what little social balances that we have.

        Somehow I think some
    • Are we looking for a God replacement?

      Can you really replace something that doesn't exist, at least not outside the realm of human imagination?

    • As Harvard professor Steven Pinker says in his best-seller "The Language Instinct"- humans are compulsive communicators. So when we have the ability to communicate with E.T.'s (or dolphins) we will try to do so.
    • KARMA WHORE!

  • What about STI? (Score:3, Funny)

    by Scot Seese ( 137975 ) on Monday April 21, 2003 @11:24AM (#5773415)
    We need a department of the Search for Terrestrial Intelligence. ;(

  • How many LoCs of data does the 8 football fields of dishes generate, and what's the BogoMIPS rating on their obligatory Beowulf cluster?
  • Has this array identified San Francisco as a potentially habitable host?

    If it has then we are in trouble.

  • Vegans (Score:3, Funny)

    by SecretAsianMan ( 45389 ) on Monday April 21, 2003 @01:04PM (#5774136) Homepage
    ...at least we don't have to worry about them wanting to eat us!
    • OMG!!

      The parent of this post was so funny that I had to go to the fridge, get a full glass of milk, and spit it up through my nose!

      -- Terry
  • the array spans an equivalent 8 football fields.
    C'mon, now, you think us geeks have ever actually been on a football field to know how large it is? We need this measured in something useful -- like, libraries of congress.

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