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Space Science

Earth's Corner of the Galaxy Just Got a Little Lonelier 224

Hugh Pickens writes "Only four stars, including Barnard's Star, are within six light-years of the Sun, and only 11 are within 10 light-years. That's why Barnard's star, popularized in Robert Forward's hard-SF novel Flight of the Dragonfly, is often short-listed as a target for humanity's first interstellar probe. Astronomers have long hoped to find a habitable planet around it, an alien Earth that might someday bear the boot prints of a future Neil Armstrong, or the tire tracks of a souped-up 25th-century Curiosity rover. But now Ross Anderson reports that a group of researchers led by UC Berkeley's Jieun Choi have delivered the fatal blow to those hopes when they revealed the results of 248 precise Doppler measurements that were designed to examine the star for wobbles indicative of planets around it. The measurements, taken over a period of 25 years, led to a depressing conclusion: 'the habitable zone around Barnard's star appears to be devoid of roughly Earth-mass planets or larger ... [p]revious claims of planets around the star by van de Kamp are strongly refuted.' NASA's Kepler space telescope, which studies a group of distant Milky Way stars, has found more than 2,000 exoplanet candidates in just the past two years, leading many to suspect that our galaxy is home to billions of planets, a sizable portion of which could be habitable. 'This non-detection of nearly Earth-mass planets around Barnard's Star is surely unfortunate, as its distance of only 1.8 parsecs would render any Earth-size planets valuable targets for imaging and spectroscopy, as well as compelling destinations for robotic probes by the end of the century.'"
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Earth's Corner of the Galaxy Just Got a Little Lonelier

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  • by cjsm ( 804001 ) on Wednesday August 22, 2012 @07:55AM (#41079467)

    A lack of planet on a nearby star does not mean there is nothing around the star

    There might still be fragments of ice / rocks / whatever that humankind can use to construct an artificial planet of some kind

    Plus, the lack of existing planet means we get to create one, with our own design

    Yea, make our own planet. Simple! This got modded 5 Insightful? Why not make another Earth in our own solar system? It would be way easier to do it here where all the resources are, instead of in a distant solar system. Or even easier, crash asteroids from the asteroid belt into Mars to create an Earth size planet. Why don't we do it? Because it would be freakin' impossible for any beings without near God-like technological powers.

  • by Anonymous Coward on Wednesday August 22, 2012 @08:19AM (#41079569)

    "Why don't we do it? Because it would be freakin' impossible for any beings without near God-like technological powers.

    People not so long ago would have said that about many of the things we take for granted today. Try telling someone a couple of hundred years ago that we'd build aircraft that could carry hundreds of people at 2/3 the speed of sound to the other side of the planet in a few hours, or that we'd be able to pull a small device out of our pockets and talk instantly to someone anywhere on earth, or that we'd be able to send a sophisticated robot to Mars to explore and conduct science experiments. Creating an artificial planet isn't essentially that hard, it just requires a level of technology beyond where we're currently at. Get to a stage where you can send out self-replicating robots to collect and process asteroids for you, for example, and it might look a bit less daunting. And there's no particular reason to believe that we won't eventually develop such technologies.

  • by arth1 ( 260657 ) on Wednesday August 22, 2012 @08:32AM (#41079627) Homepage Journal

    Yea, make our own planet. Simple! This got modded 5 Insightful?

    The Mormon Moderation Front?

    Seriously, I can't think of anyone else who believe that humans will create planets. No, this is not flamebait or trolling - it really is the only ones I can think of that might see this as a possibility, although not while still human.

    And if there really are someone delusional enough here to think that we could create our own planet while being mortal humans, you really need to think about the scale here. It's not just huge, it's immense. We only scratch the surface of this planet.
    If we found Mount Everest sized rocks (~3x10^15 kg) in a solar system, we would need around 2 000 000 000, that is 2 milliard (or billion for those who use the short system) of them to create a planet with Earth's mass (~6x10^24 kg). Imagine the power and time needed to move one Mount Everest. Each Chomalungma sized rock is about 28 milliard (or billion in the short sytem) times the weight of the space shuttle.

    And we're not just talking scale here. Think about how you would adjust the orbital speed of the mass you assemble so it would stay in orbit as you add to it. Or how to cool it down from all that kinetic energy -- how long did it take Earth to cool down? Or how to survive the flares of Barnard's Star?

    Niven and Lucas make great space operas. But we have to admit to some limitations. Come back in a few million years, and whatever species have descended from us may have a different opinion. But us? No, we have no chance.

  • by medv4380 ( 1604309 ) on Wednesday August 22, 2012 @08:32AM (#41079629)
    Interstellar travel will probably give us that Near God-Like technological power that you seem to think will be missing. Getting there will be much harder then moving a few rocks around. Though doing it in our own solar system might be considered dangrous. Changing the existing set of gravity wells could cause any number of problems, but who cares if it's an uninhabitable solar system.
  • by dontclapthrowmoney ( 1534613 ) on Wednesday August 22, 2012 @09:17AM (#41079985)

    Why not make another Earth in our own solar system?

    I'd prefer them to use Barnard's star for beta testing the process.

  • by Sarten-X ( 1102295 ) on Wednesday August 22, 2012 @09:28AM (#41080083) Homepage

    This is exactly what I came here to say.

    One thousand years ago, the peak of technology was a powder that would explode when ignited, that could propel a small projectile in a general direction a few hundred feet. Today, the peak of technology is dropping a laser-armed nuclear-powered semi-autonomous wheeled laboratory from a rocket-powered flying crane onto a precise target from 150 million miles away.

    By the time we have the capability to load up humans and send them 1.8 parsecs away before they (and any descendents) die, we might just have the technology to build an artificial planet, or at least a large structure capable of artificial gravity, a self-sustaining ecosystem, and harvesting materials from whatever asteroids are nearby. It does not need to be as big as the Earth or support as large a population, but it'll do for a while until technology improves further.

  • by arth1 ( 260657 ) on Wednesday August 22, 2012 @09:31AM (#41080125) Homepage Journal

    Getting there will be much harder then moving a few rocks around.

    Um, no. A planet isn't just "a few rocks". The scale is immense, and we're bound by the laws of physics and thermodynamics.

    Never mind where we would get the energy to accelerate and decelerate such masses from, it would likely take thousands of millions of years to assemble those "few" (thousands of millions) gargantuan rocks and have the new planet cool down enough to be ready for terra-forming.

    Getting there isn't even in the same fantasy as creating a planet. There are orders of orders of magnitude difference here.

  • by tarius8105 ( 683929 ) on Wednesday August 22, 2012 @09:45AM (#41080313)
    Easier said than done. There would be a lot of new science required just for planet terraforming that does not exist today. An example, how to make the planet's core more active to support tectonic plates so that the rock material from crashing asteroids into the planet get recycled into larger rocks. Then there is calculating the right amount of liquid water needed to sustain the planet and somehow transport it whether its crashing comets into the planet. Altering the planet's rotation if its tidally locked, its axis if we want to have seasons (which I believe would be required), and potentially a moon with enough mass to exert influence to maintain them. The other issue is this isnt something that is currently completable in the average person's life time, it would be many generations down the line where they might be able to work on phase 2.
  • by Drethon ( 1445051 ) on Wednesday August 22, 2012 @09:50AM (#41080379)
    Yeah I mean what's with people who think humans can fly? There are just things that humans were not meant to do!

    Everything is impossible until you figure out how to make it possible...
  • by Anonymous Coward on Wednesday August 22, 2012 @09:52AM (#41080399)

    capable of artificial gravity,

    You want some faster than light travel with that?
    Or perhaps telekinesis?

    Artificial gravity can easily be implemented with acceleration. Pretty much every amusement park out there have a "large" structure capable of artificial gravity. They usually create a gravity-like force out from the center but sometimes they create a transient gravity-like force, either upwards or downwards from earth to increase or decrease the real gravitational force you fell form the planet.

    Faster than light travel is a bit harder since traveling at light speed isn't supported by current models. If the models we use today turns out to be wrong it might be possible. We still havent figured out why we get anomalies like dark matter with the models so it's not impossible that there is something wrong with them. OTOH we haven't observed anything moving faster than light either so it's likely that the energy requirement for moving faster than light is too high for it to be possible to occur naturally or that things moving faster than light don't interact in a way that can be observed.

    Telekinesis is spiritual superstition and belongs to fantasy, not science fiction.

  • by arth1 ( 260657 ) on Wednesday August 22, 2012 @09:57AM (#41080441) Homepage Journal

    Yeah I mean what's with people who think humans can fly? There are just things that humans were not meant to do!

    Everything is impossible until you figure out how to make it possible...

    This isn't just a technical issue, unless Newton, Carnot and Einstein were all wrong in pretty radical ways.
    Scoffing at building a planet is more like scoffing at someone who says he can eat the moon. It's not just a question of getting and preparing the moon - there's not enough time for it to happen in.

  • by Nadaka ( 224565 ) on Wednesday August 22, 2012 @10:24AM (#41080769)

    This is actually pretty much true.

    By the time we have the technology to smash together enough rocks that it can hold an atmosphere with its natural gravitational force, we won't need to live on a rock with enough natural gravitational force to hold an atmosphere.

    That godlike amount of effort could be spent doing something more practical.

  • by Drethon ( 1445051 ) on Wednesday August 22, 2012 @11:00AM (#41081291)
    The idea of flight still applies. Flight of something that has all of its thrust propelling it forward seems impossible until we understood how a wing can produce lift. Yes the necessary forces to produce a planet in a sane amount of time are quite a bit different from that of a wing and may not exist at all. However we can't assume we know everything about how the universe works since our theories keep getting proven wrong (or incomplete). Unless we understand that there may be forces to the universe we don't know about yet, we will not recognize them when we finally see them.
  • by bzipitidoo ( 647217 ) <bzipitidoo@yahoo.com> on Wednesday August 22, 2012 @12:03PM (#41082157) Journal

    Doesn't sound like you appreciate the difficulties of doing an interstellar probe. It's not like silicon chips, in which we've seen astounding improvements. We simply can't do it, not now, and probably not in the next 20 years or even 100 years.

    Currently, our fastest escaping probe is Voyager 1, at about 17 km/s relative to the sun. At that rate, a probe will need about 70000 years to reach Alpha Centauri. Suppose the velocity we can give probes improves by a factor of 100, which is assuming a lot. (For one thing, gravity assists would be of little value.) That's still 700 years. We have no experience making machines that can last that long. Our civilization might not last that long. We need perhaps 1000 times the velocity, then we're talking only a 70 year wait.

    To achieve 1000 times the velocity is not a matter of 1000 times the fuel, it's 1000^2 times the fuel. It's even worse than that, if the probe has to carry its fuel. No matter how we accelerate the probe-- whether with on board ion drives, nuclear bombs, light sails, or something else-- that's such a huge amount of energy that none of these ideas are even remotely feasible. That means it will have to be slower, which puts us back to the problem of how to build something that can last the 1000 plus years such a trip will take. There are many other problems, such as communication, but the primary one is simply the distance. I wouldn't hold my breath for science fantasy either. It's not at all likely we will invent warp drive or some other means of FTL travel.

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