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Space Science

Earth-Sized Planets Confirmed -- But They're Dead 73

Posted by timothy from the venn-diagrams dept.
tizo writes "Robert Britt wrote an interesting article about the discovery of three Earth-sized planets confirmed after ten years of controversy. They orbit a pulsar, a neutron stars spinning very rapidly. Researchers pinned down the masses by watching how the planets affect pulses of energy coming from the star. All other known planets around other stars are much bigger (like Jupiter) and were found using other techniques (Doppler effect of main star moving in a close circle because of influence of the planet or direct transit over line of sight)."
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Earth-Sized Planets Confirmed -- But They're Dead More

Earth-Sized Planets Confirmed -- But They're Dead

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  • Of course they are dead... (Score:5, Funny)

    by Sevn ( 12012 ) on Wednesday June 04, 2003 @12:40PM (#6116061) Homepage Journal
    EVERYBODY knows that class M planets almost always
    end up smoking husks because the inhabitants attempt
    to discover the mass of the higgs boson particle and
    waste themselves.

  • how to find... (Score:5, Informative)

    by Ransak ( 548582 ) on Wednesday June 04, 2003 @12:40PM (#6116065) Homepage Journal


    extrasolar planets. [esa.int]

  • keep denying it... (Score:5, Insightful)

    by ceejayoz ( 567949 ) <cj@ceejayoz.com> on Wednesday June 04, 2003 @12:45PM (#6116105) Homepage Journal
    It always amuses me when discoveries like this get made. I've had arguments with people who claim Earth is unique, and those arguments have gone from "extrasolar planets can't exist" to "earth-sized planets can't exist" - and now, they'll likely go to "earth-sized planets in the habitable zone can't exist" (which is bullshit, because the habitable zone only applies to our particular ecosystem)...

    Sigh... I imagine these same people will claim that it's all a big illusion when we discover an earth-like planet.
    • Sigh... I imagine these same people will claim that it's all a big illusion when we discover an earth-like planet.

      I want to see what they say if a massive flying saucer comes down and sits on top of a few dozen of the largest cities on Earth.

    • Re:keep denying it... (Score:3, Insightful)

      by upper ( 373 )
      which is bullshit, because the habitable zone only applies to our particular ecosystem

      Pulsars are the remains of massive stars, and massive stars don't last very long. So life wouldn't have had a chance to get started there.

      And we don't know how big they were before their star went supernova. I'm no astrophysicist, but I'd guess they were Jupiter-class, and everything but the core got stripped away.

      • Oh, I'm not disputing that this particular system is dead. I'm just saying that the so-called "habitable zone" is silly, because it assumes that life can only be like life on Earth.
        • No, it's not silly.
          Because live will be based on chemistry (and we couldn't detect anything else anyway) - and chemistry sets some rules.
          For example the speed of chemical reactions - below a certain temperature they're much too slow for anything interesting to happen.
          And above a certain temperature no big molecules can form.
          Thus we have a definite upper and lower temperature boundary.
          And not only that we know for example that big stars are much too short lived for live to form - and that stars with too high
          • However, life is possible far outside what is normally called the "habitable zone". Liquid water on Europa would allow life. Life may be possible on Titan's surface, or in the upper atmosphere of Jupiter. It's certainly possible to have microorganisms thriving on Mars - hell, some Earth bacteria could likely survive there.
          • And that asumes that the life is based upon chemical reactions.

            Does it have to be? Probably, but I wouldn't discount something energy based. Not that we would probably even recognise it as living.

            OK, OK waaay to much sci-fi.
      • I doubt it.

        Jupiter Class planets tend to have liquid metallic hydrogen at their core. That stuff tends to get a little unstable when you strip off the outer layers of the planet.

        Besides RTA. The smallest is about 2 times the size of the moon.

    • Re:keep denying it... (Score:3, Informative)

      by Alsee ( 515537 )
      those arguments have gone from "extrasolar planets can't exist" to "earth-sized planets can't exist" - and now, they'll likely go to "earth-sized planets in the habitable zone can't exist"

      It sounds a lot like the ever-shrinking "god of the gaps" [colorado.edu] arguments.

      -

  • The're dead, Jim! (Score:5, Funny)

    by warpSpeed ( 67927 ) <slashdot@fredcom.com> on Wednesday June 04, 2003 @01:05PM (#6116267) Homepage Journal
    Damit, I'm a doctor, not an astrophysist.

  • Not necessarily dead... (Score:5, Insightful)

    by pmz ( 462998 ) on Wednesday June 04, 2003 @01:18PM (#6116421) Homepage
    at least at some point in time. For example, our solar system has been around for only a fraction of the life of the Universe. Whole ecosystems and, sometimes, civilizations can come and go in a moment's time (from the Universe's point of view...if it had a point of view...well, you understand).

    It is actually very unlikely that we would witness a civilization in a state similar to our own. They would most likely be millions or billions of years behind or ahead of us. Would we even be able to recognize one even a million years ahead of us? It seems life forms like to do things exponentially...
    • Our planet has been arround for 4.6 billion years, about 1/3 the time of the universe. That could mean that for every 3 earth-sized planets that has been alive at some point in the last 15bn years, that we see, one of them should be in a "living" form, whether thats a 20th century civilisation, dinosaurs, or volcanic eruptions.

      But then our sample size isnt exactly enourmous.
      • Further whittling it down is the fact that first generation stars wouldn't have the heavy elements in thier planetary disks nessissary for rocky planets or any complex molecules to form. The first stars that could have rocky planets formed about 5 billion years after the big bang, and therefor Earth has been around for about 1/2 the period in time in which a rocky planet could have existed.
        • We could probably whittle it down to ignore the first couple billion years of an earth-type planet's formation - there wouldnt be much support for life (as we know it) in those conditions.

  • There is an infinite number of earth like planets (Score:3, Insightful)

    by IdleTime ( 561841 ) on Wednesday June 04, 2003 @01:21PM (#6116452) Journal
    Based on the share number of galaxies and stars within each galaxy, mathematics would dictate that there are close to infinte numbger of earth like planets.

    Will we ever find a planet similar to our Earth with life similar to our on it? Maybe, but the chances are extremly slim based on the the enormous distances we are talking about.

    Based on this I would also say the chances are extremly slim that we will ever make contact with other intelligent beeings in the Universe. Maybe we ought to consider the possibility that intergalactic spacetravel is not physically possible hence we will never meet "aliens" from other planets?
    • if there were an infinite amount of Earths revolving around an infinite amount of Stars, then there would be an infinite amount of lifeforms in an infinite amount of galaxies, each with an infinite amount of monkeys who write books.

    • Re:There is an infinite number of earth like plane (Score:5, Insightful)

      by Larthallor ( 623891 ) on Wednesday June 04, 2003 @01:50PM (#6116694)
      Actually, it depends on what you mean by "contact". If you mean two-way communication, I happen to agree. We'd have to get EXTREMLY lucky to be close enough in time and space to a sufficiently similar species to be able to hold an effective conversation.

      However, we have a much better shot at hearing the echoes of long dead civiliations coming to us from other systems. Remember that each signal goes flying out in a sphere around the transmitter at the speed of light. Therefore, much of the statistical problems with time/space coincidence go away. We are currently being bathed in emissions from systems 4.5 light years to nearly 14 billion light-years away. That's a lot of history to be receiving at one time and there's a shot that some of those emissions will be coming from machines created by intelligent beings.

      Of course, the idea of sitting in a radio observatory listening to the whispers of a race that's been dead longer than our planet has existed is a lot less exciting than coming out of hyperspace, engines audibly blazing in the vacuum as the crew realizes that "that's no moon." Still, it would be pretty exciting to me.
    • "Maybe we ought to consider the possibility that intergalactic space-travel is not physically possible hence we will never meet "aliens" from other planets?" Perhaps. But this is also possible: They aren't interested in space. The galaxy has some superpowers, who are for the moment at peace. With Earth in the middle of the DMZ. They are interested in space, but simply not in us. ("Look at those silly humans. Can't even get of their own planet")

    • "Maybe we ought to consider the possibility that intergalactic spacetravel is not physically possible hence we will never meet "aliens" from other planets?"

      Less than one hundred years ago, we didn't think atom bombs were possibly, much less even conceive of them. Less than thirty years ago, there was no idea of what we would be capable in 2003. I wouldn't dismiss the idea of FTL travel just because I can't conceive it yet. Nature seems to always leave some way to do something that we didn't think possible

      • We didn't have theoretical reasons on the impossibility of certain things like atomic bombs or computers in every home or whatever else, only technical doubts whether it would have been feasible (or pratical enought) or not.

        To say that strictly speaking FTL travel is possible would mean to throw away most things we consider true about life, the universe and everything. I'm not saying that this is impossible, only that it is not easy, not that likely in the next couple of centuries of so and extremely unpl

        • Actually you wouldn't have to break the laws of physics to travel faster than light. You just need to find ways around them. Generating a 'hole' in spacetime might allow you to move quickly from one area to the next. My personal favorite though is 'bending' space by creating huge gravity well do that the two points you want to travel between are no longer far away. In both instances you travel a distance faster than light could, but you never moved faster than the speed of light.
    • What is this "close to infinite" business anyway ...
    • "Based on the share number of galaxies and stars within each galaxy, mathematics would dictate that there are close to infinte numbger of earth like planets."

      Ummm... no it wouldn't. If you multiply two very large numbers together, no matter how big they are, infinity is still much, much bigger.
    • How can you ever get "close" to infinite?
    • What bugs me is this common assumption that interstellar and intergalactic spaceflight necessarily implies faster-than-light spaceflight. It may be a long, boring trip, but the technology already exists to get somewhere eventually, and within a century we may be able to go very close to the speed of light (with Bussard Ramjets or something similar).

  • Earth-Sized Planets Confirmed -- But They're Dead (Score:5, Funny)

    by cgenman ( 325138 ) on Wednesday June 04, 2003 @02:28PM (#6117095) Homepage
    My goodness, can you imagine what would happen if we found an Earth-sized planet that was alive? What would it eat?

    It would be like the Transformers Movie all over again.

  • There's little chance of life "as we know it" existing post-supernova, but if these science writers read much science fiction, they'd have the chance of thinking that other kinds of life could be there.

    Examples:

    • Dragon's Egg - Robert L Forward
    • Diaspora - Greg Egan
    • Eon, Eternity - Greg Bear

  • Ten years of controversy? (Score:5, Informative)

    by pq ( 42856 ) <rfc2324&yahoo,com> on Wednesday June 04, 2003 @03:45PM (#6117892) Homepage
    I don't know about "ten years of controversy" - these things have been around since 1992 and pretty widely accepted. Here's the original Nature abstract [harvard.edu] (1992) and here's Alex W's ADS entry [harvard.edu] - there's a pretty steady stream of PSR B1257+12 papers, and not much in the way of controversy.

    But yes, it is extraordinarily neat!

  • does every1 hope for life elsewhere?

    I'm not sure I do, without it sounds just as exciting.

    I'm sure we'll find something but it'll redefine what `life` is probably anyway.

    • does every1 hope for life elsewhere?

      I do. If nothing else, it would indicate that we don't have the only inhabitable oasis in the entire universe. It also means that, should we manage to nuke ourselves into oblivion, then other civilizations can hopefully keep going - it's not the end of the universe's only experiment with intelligent life. That's kind of comforting in a bleak way.

      • ah, that's true i suppose.

        perhaps because I'm a pesimist at heart, I feel that if we do find life elsewhere that it would likely to be vastly different from our own. I expect conditions in which life might have started elsewhere to be completely different.

        The leading scientists in the search for exterrestrial life are looking for similar conditions to earth, so is it irrational for me to expect conditions to be radically different?

        I'm finding it hard to determine wether my belief is based reason or j
  • AFAIK neutron stars form from a supernova and they are the second most dense objects after the black holes. How can any planets survive the supernova blast of the original star?

  • Could take a little while to get there...

    Distance from Sun: 2630 Light Years
    • Well Duh. Did you feel the shockwave from any supernova lately. No, I don't think so.

      Let's see, if memory serves me right... the last time a supernova happened near us.... Hmmm, OH YEAH, it caused our solar system to coalesce from the cloud of gas left over from the one before that.

      Sorry, Tired. Becoming Sarcastic. Can't stop self. Help...

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