Slashdot is powered by your submissions, so send in your scoop

 



Forgot your password?
typodupeerror
×
Space Science

First Image of Extrasolar Planet Confirmed 118

An anonymous reader writes "The year-long controversy about whether the European Southern Observatory had indeed captured the first picture of an extrasolar planet has apparently been resolved. Journal publication today of a fuzzy image of this Jupiter-sized, extrasolar planet led Christophe Dumas, a member of the discovery team, to say enthusiastically: 'The thrill of seeing this faint source of light in real-time on the instrument display was unbelievable. Although it is surely much bigger than a terrestrial-size object, it is a strange feeling that it may indeed be the first planetary system beyond our own ever imaged.'"
This discussion has been archived. No new comments can be posted.

First Image of Extrasolar Planet Confirmed

Comments Filter:
  • Argh, my science project is now ruined..
  • "Small" correction (Score:5, Interesting)

    by Space cowboy ( 13680 ) * on Saturday April 30, 2005 @03:19PM (#12393289) Journal

    It's actually (according to the BBC and eso.org) 5x the size of Jupiter, or about half the size of our sun. Calling it a mere planet may be a bit harsh - Jupiter itself is a net producer of energy (radiated = 2x incident, roughly), and it's speculated that this is due to gravity forces. This gas-giant 'planet' is presumably more active gravitationally - perhaps 'proto-sun' or 'failed sun' might be a better description (except that discovering a planet is a far greater acheivement than a tiny star...

    Simon.
    • by LiquidRaptor ( 125282 ) <Matt@sMENCKENix9s.com minus author> on Saturday April 30, 2005 @03:26PM (#12393337) Homepage
      You know I've often wondered about why these big planets are failed suns. I seem to remeber hearing somewhere that anything much bigger than jupiter would collapse in on itself due to gravitation. I wonder if theres not some form of fusion going on in the core that exerts an outward pressure on these big planets.
      • by peculiarmethod ( 301094 ) on Saturday April 30, 2005 @03:38PM (#12393396) Journal
        while thats a great idea, and I do not profess to have an answer, I would like to remind you that fusion would not be the easiest solution. I would recommend looking into the specific densities of the materials making up the massive object.. perhaps on average lighter materials (from young stars) were used in creation of these objects. Perhaps the object was formed from two larger object on similiar paths (created near each other, falling into each other later in the development game. Again, I am not sure, but it seems correct in experience to look for the easiest possible solution, and test those first. I dunno.
        • by zippthorne ( 748122 ) on Saturday April 30, 2005 @04:12PM (#12393583) Journal
          When considering density you must also consider the pressure. The earth for instance is denser than its composition would be at sea level because of the tremendous forces resultant from its own mass.

          It is suspected that the core of jupiter is metallic hydrogen, a phase that occurs only at extreme pressures.

          As an aside: The earth is also a net "producer" of energy if you look at luminosity alone. All of the energy from solar radiation must be radiated away or we'd become very hot very quick. In fact, it's a bit worse than that since some heat is also escaping from the core. Evidence: volcanoes. so the total amount of energy leaving the earth as light must therefore be greater than the total amout of energy intercepted by earth as light.

          I think most of us would agree that the earth is not "generating" heat, but rather just slowly dissipating the heat that's already there. from the formation of Earth. Io on the other hand is generating heat (or rather heat is being generated as a result of jupiter's tidal forces.)
          • The interior of the Earth is also heated by the decay of radioisotopes. It is hotter than what would be caused by tidal forces and residual heat left over from it's formation.
      • by Scott Ransom ( 6419 ) <`sransom' `at' `nrao.edu'> on Saturday April 30, 2005 @03:54PM (#12393479)
        Note: IAAA

        The reason why they are called failed suns is because they are. Gravity pulls the matter in towards the center of the planet. This makes the center hot and dense (think ideal gas law). If there is enough mass in the planet, the gravitational attraction is strong enough that it forces the pressure and temperature at the planets core to exceed the thresholds required for nuclear fusion (hydrogen to hydrogen) to occur. If the body is massive enough to do this it is a bona-fide star. Stars slightly less massive are known as brown dwarfs (there are technical reasons why they are not called planets), and bodies even less massive are planets.

        Jupiter is giving off heat because the gravitational attraction is causing the temperature and pressure inside the star to be relatively high -- just not high enough for fusion.
        • The question is, given the proposition that any thing 'much' bigger than Jupiter should form a star, why would something that meets that threshold not form a star?
          • My guess would be that by "bigger" they actually mean more massive. There should be a critical mass, where the weight of the planets mass creates so much pressure that at the center, the electromagnetic force is overcome and fusion begins. My guess would be that if this planet is 5x the size of jupiter and is not a sun then it would probably be about 1/5 the density, so that its overall mass would still not be sufficient to crate the forces necessary at its center for the fusion process to begin. Remembe
          • by mikael ( 484 ) on Saturday April 30, 2005 @05:18PM (#12393911)
            From the article on Jupiter [msn.com]

            A. Composition of Jupiter

            The fact that Jupiter's radius is 11.2 times larger than Earth's means that its volume is more than 1,300 times the volume of Earth. The mass of Jupiter, however, is only 318 times the mass of Earth. Jupiter's density (1.33 g/cm3) is therefore less than one-fourth of Earth's density (5.52 g/cm3). Jupiter's low density indicates that the planet is composed primarily of the lightest elements--hydrogen and helium.

            The computer models predict that Jupiter's outer layer, composed of a gaseous mixture of hydrogen, helium, and traces of hydrogen-rich compounds such as ammonia, methane, and water vapor, is about 1,000 km (about 600 mi) thick. Beneath this layer, the pressure is so great and the atmosphere is so hot and compressed that the hydrogen and helium atoms do not behave as a gas, but as what physicists call a supercritical fluid. Supercritical fluids form at high temperatures and pressures and have properties similar to those of both gases and liquids. The supercritical zone extends 20,000 to 30,000 km (12,000 to 19,000 mi) into Jupiter, which is about one-fourth to one-third of the radius of the planet.

            Beneath the supercritical fluid zone, the pressure reaches 3 million Earth atmospheres. At this depth, the atoms collide so frequently and violently that the hydrogen atoms are ionized--that is, the negatively charged electrons are stripped away from the positively charged protons of the hydrogen nuclei. This ionization results in a sea of electrically charged particles that resembles a liquid metal and gives rise to Jupiter's magnetic field. This liquid metallic hydrogen zone is 30,000 to 40,000 km (19,000 to 25,000 mi) thick--about half the radius of the planet--and extends to the molten rock core at Jupiter's center. The molten rock core occupies a sphere with a radius of about 10,000 km (about 6,000 mi)--about one-fourth of Jupiter's total radius--and has a mass perhaps 10 to 15 times the mass of Earth.

            In order for a cloud of hydrogen gas to form a star, both gravity and pressure have to overcome the various fundamental forces that prevent atoms from fusing together,/a> (weak, electromagnetic). [gsu.edu]

            In ratio to the "strong force" which holds the nucleus of the atom together, the electromagnetic force is 1/137, the weak force is 1/(10^6), and gravity is 1/(10^39).

            Thus gravity is 10^37 times weaker than the electronmagnetic force, and 10^33 times weaker than the weak force. So you are going to need a considerable amount of mass to overcome these forces.

            Another factor is Newton's Universal Law of Gravitation:

            F = G . m1 . m2 / ( r^2)

            where G is the Gravitational constant
            m1 and m2 are the masses of two objects (eg. hydrogen atoms, dust, asteroids, ...)
            and r is the distance between the two objects

            The implication of this equation is that gravitational forces become greater the closer the two objects are. So the gas cloud has to pull itself together from gas to liquid (a liquid cannot be compressed any further). At this stage, pressure is created, and gets converted into heat (electromagnetic force)

            If there isn't enough mass, a sufficiently deep gravity well won't form, and you will end up with a superhot liquid gas planet - which is more or less what Jupiter is.
        • So, your are an Insurance Advisers Association of Australia Incorporated. Good for you. Now what do YOU know about astronomy? :) http://www.google.ca/search?hl=en&q=IAAA&btnG=Sear ch&meta= [google.ca] Lousy abreviation I tell ya!
      • by imsabbel ( 611519 )
        Well, actually lots of people working in that area asked themselves the same question :)

        Yes, there are non-stars that dont support "normal"fusion but still create energy by deuterium fusion. But even for this a limit can be calculated.
        Normal Hydrogen burning stars start at around 7% of the mass of the sun, deuterium burning ones are normally called brown dward and start around 1.5% of M_sol. So still about 3 times that of this planet here.

        You have to understand that those fusion processes are EXTREMELY te
    • by at_18 ( 224304 ) on Saturday April 30, 2005 @03:39PM (#12393404) Journal
      It's actually (according to the BBC and eso.org) 5x the size of Jupiter, or about half the size of our sun

      Remember that when astronomers talk about "size", they are actually talking about mass. Our sun is 1000x the mass of Jupiter, so this planet is still 200x smaller.

      The minimum mass to call a big planet a "star" is about 70 times Jupiter (that's the minimum mass to start nuclear fusion).
      • by mbrother ( 739193 ) * <mbrother.uwyo@edu> on Saturday April 30, 2005 @09:17PM (#12395315) Homepage
        Careful astronomers don't make this mistake, but we're talking about results massaged by PR people and the press. I've been through that experience, and it makes me always go to the journal article or preprint to determine what they're actually talking about.

        Personally, I would never use "size" for mass, and geometrical sizes are still ambiguous. Is a size a radius, surface area, or volume? Each of the three could be the answer under different circumstances.

        The best estimates I recall are more like 80-82 Jupiter masses for fusion, a little bigger than 70. I remember being irritated with Arthur C. Clarke's 2010 for saying that if Jupiter were only "a little bigger" it would be able to have fusion processes and be a star. My little bigger above is for 10% bigger, not a factor of 80 times bigger. I don't think that's being picky, I think that's just Clarke being wrong in that case.
        • With all the screwups by the popular media, ala in this article bigger = size instead of mass, do you think that enough scientists/people misquoted by the media will just stop talking to them, forcing them to have higher standards? Or will it be that the charletons and fools fake being scientists and everyone has even less correct information? Or is it something like choice 3, cowboyneal?
        • I don't think I agree with you about what "a little bit is"

          In something you normally talk about in linear measurement, I might agree with you about 10%. But for a topic (like planets) where the range is variable enough that it makes sense to talk about the magnitude of the number, not the number (10^28 m etc) and where those exponents are high, 10% isn't even part of the number you're talking about. That's from a language point of view.

          From a physical point of view, it's very reasonable to assume that
          • Two orders of magnitude isn't a little bit in astronomy, one of the most liberal fields in terms of accuracy (both because the ranges are so large and because the measurements are so difficult). As a side point, be careful about the relationship between size and mass in stars -- there are regimes where mass increases reduce the diameter, and it also depends on the age of the star/planet.

            I put my money where my mouth is. I write science fiction novels and critique the hell out of my own work and those of
            • I don't have a copy of 2010 handy, and I'll admit to not remembering the passage you're referring to. I'm also aware of the not-necessarily linear size-mass relationship.

              If some other posts in this article are correct it may be closer to 1/4 than to 2 orders of magnitude. I'm not at all convinced that AC may not have had reason to believe it wasn't even less (or perhaps would be discovered to be less)

              I'm a fan of old-school science fiction, and I hugely appreciate the work that goes into making a good s
    • by Rakshasa Taisab ( 244699 ) on Saturday April 30, 2005 @03:50PM (#12393458) Homepage
      Wrong, this planet is *not* 5x the size of Jupiter. It has a *mass* 5x that of Jupiter. Due to gravity etc no planet can grow much beyond the size of Jupiter. Don't remember the exact size but it was some 10-30% larger that was the limit.
    • It's not accurate to say this object is "half" the size of the sun.

      The planet in question is 5 times the mass of Jupiter. The sun is about a thousand times the mass of Jupiter.

      I think you're confusing mass with diameter. Jupiter's diameter is indeed approximately one-tenth the diameter of the sun.
    • It is not really accurate to say that "Jupiter itself is a net producer of energy". Is Jupiter a net EMITTER of energy? Yes, but this energy is the leftover heat of formation from the protoplanet nebula. D+D fusion does not happen in Jupter. Incidentally I predict "planet" imaging simillar to this will become commonplace in about 2 years when VLTI interferometric imaging comes online [eso.org].
    • I wonder what is the Earth's total radiated energy (radio/TV, streetlights, geothermal, etc), compared with our incident energy.
      • It should be roughly similar, given that if we radiated less than the sun put in it would be getting uncomfortably warm around here just now.

        I don't think the quantity of heat from the sources you've mentioned is significant though when compared to the source under our own feet...
        • We do reflect less than the insolation - it's why our albedo is less than 100%, and how all the surface ecology and meteorology is powered. My question is just what percentage do we generate synthetically, compared with the insolation. I don't know what would be "significant" (or of what), but I'm interested in our human contribution.
    • You sound a bit confused regarding mass/size/diameter etc...
  • by Future Man 3000 ( 706329 ) on Saturday April 30, 2005 @03:20PM (#12393298) Homepage
    Is that the planet is something like five times as large as Jupiter, which defies all known data about planetary formation.

    That, and it's orbiting a brown dwarf.

    • by Anonymous Coward on Saturday April 30, 2005 @03:23PM (#12393316)
      "That, and it's orbiting a brown dwarf."

      Excuse me, but the politically correct term is Ethnic Little Person. Mmkay?
    • One small note: "co-moving" and "orbiting" are not the same thing. They have enough evidence to suggest that they are co-moving. But that doesn't necessarily prove (nit-pick, I know) that they orbit each other. That'll be proven in follow-up observations.
      • Ok, so what you are saying is the two bodies which are as massive as the brown dwarf/planet, are very near to each other, and co-moving, and yet the gravitational forces of said bodies are not sufficient enough to warp spacetime sufficiently to effect the orbit of the other body?

        -kaplanfx
        • No. Gravity affects every body. But there is a difference between gravitationally affected and gravitationally bound.

          The sign of co-moving is a pretty good indicator that the system can be bounded (but you can't exclude a possibility that these stars are merely in the same association and the direction of their motion is coincidental). To establish that the planet is bound to the brown dwarf, one needs to examine its orbital path, which requires more data points in future.
        • I have hot heard this term co-moving before but it may be close to what I understand the relationship is between the earth and the moon.

          If we were not living on the earth or the moon we would be more objective and not call the moon our satellite. We would instead call it a double planet.

          The moon is so large compared to the earth that if you drew the paths of the two bodies relative to the sun you notice that the moons orbit around the sun is never concave.

          The moons orbit gets straighter when closer to t
    • What's interesting about this... Is that the planet is something like five times as large as Jupiter, which defies all known data about planetary formation.

      Update: The planet was discovered shortly after a bout of sneezing around the telescopes. New speculation has emerged that the giant planet is composed of phlegm.

      That, and it's orbiting a brown dwarf.

      "We prefer to be called people of extraterrestrial-melanin-enhanced-skin-vertically- challenged", said a spokesextraterrestrial.

    • With much more resolution, they'll soon be able to capture Kirstie Alley's ass! Mmmmm... I look forward to that.
    • Well, when they talk about size they mean mass. As pointed out earlier..planets can not be a whole lot bigger than jupiter. They just get more dense.
  • E.T. phone home.
  • by Timesprout ( 579035 ) on Saturday April 30, 2005 @03:32PM (#12393368)
    untill it has a starbucks
  • by mmThe1 ( 213136 ) on Saturday April 30, 2005 @03:39PM (#12393403) Homepage
    Here's [mirrordot.org] the mirrordot link for the "picture" page in the story.

    The actual page has started showing signs of fatigue due to slashdot effect, so use the above link.

  • Summary (Sep 10, 2004): Faint, failed stars like brown dwarfs are borderline planets themselves, but the European Southern Observatory atop the Chilean mountains may have imaged what could be the first infrared view of an extrasolar planet.


    Well, at least the news is only 8 months old... interesting nonetheless...
  • by helioquake ( 841463 ) * on Saturday April 30, 2005 @03:56PM (#12393493) Journal
    The key issue is whether the suspected planet is at the same distance as the brown dwarf [and I assume that we know accurately enough about the distance to the brown dwarf].

    Since these stars are co-moving, it is very likely that these objects are either formed out of the same primodial materials (ie., these stars are in the same association) or gravitationally bound (i.e., the suspect planet revolves around the brown dwarf). The evidence of the co-moving alone doesn't necessarily prove that the stars are bounded by gravity, but the accuracy of their measurements probably suggest that it's pretty darn likely. Further studies are necessary to derive the orbits for sure.

    Anyway, once you establish the distance, one can figure out its true brightness of the suspected planetary object. That helps you narrow down the mass of that object (which is nailed down to be about 5x the mass of Jupiter). Combined with the "color" information of the object, these scientists makes a conclusion that this is indeed a planet.

    By the way, these objects are separated by the whooping 0.7 arcseconds. Its apparent seperation is 5 times greater than the apparent size of Pluto or something like that. You don't really need use the Hubble for studying something like this.
  • by isny ( 681711 ) on Saturday April 30, 2005 @03:58PM (#12393498) Homepage
    That's not a planet...
    It's a space station
  • by BigBuckHunter ( 722855 ) on Saturday April 30, 2005 @04:06PM (#12393548)
    Holy Crap!

    A planet discovered by a scientist named "Dumass" and not a single +5 funny yet?

    BBH
  • Am I the only one that saw the name "Dumas" and thought "Uranas has already been discovered"?
  • My perspective... (Score:4, Interesting)

    by ArbiterOne ( 715233 ) on Saturday April 30, 2005 @04:12PM (#12393581) Homepage
    I actually work at the ESO [eso.org], at the Technische Universitaet Muenchen in Garching, Germany. This is a major event for them up there- (I'm surprised it made /., they usually discourage it as they discouraged me from posting about the Venus Transit last year) . Generally, they have to fight hard to get funding from the government (although Europe is nicer about astronomy (as opposed to stuff like the ISS) than the US), so something like this is great. It incites public interest in astronomy, which is always needed for scientific institutions such as this.
    • "This is a major event for them up there- (I'm surprised it made /., they usually discourage it as they discouraged me from posting about the Venus Transit last year) . Generally, they have to fight hard to get funding from the government..."

      And....Do they maybe see a connection here....?

      I love the stuff ESO and ESA are doing but honestly, they have a LOT to learn about pr. They made watching the live Huygens Titan landing (surely the achievement of this decade for them in terms of planetary/moon explora
      • There have still been no images released from the high res imager HSRC.

        Actually, plenty [berlinadmin.dlr.de] of HSRC images have been released already, but the fact that you didn't know that just proves your point about ESA being bad at PR. (Or do you mean the Super Resolution Channel of the HSRC? Because you may be right about that, I can't find anything. If so, my apologies.)

    • Shamefully, in my haste to post such a curmudgeonly criticism I failed to congratulate you on the achievement your organization has accomplished. Very well done!! and I hope to see more of the same from ESO in future :)
      • Hey, it's not me- I'm in a different division.
        ESO does release a lot, it's not just as average-person friendly as, perhaps, NASA is. I think ESO actually does a lot more heavy-duty scientific research than NASA, and is more focused on actually using the data they collect, not just putting it up. Check the Outreach site, though- lots of good stuff there.
  • For a brown dwarf, it's awful bright blue and green!
  • Let's call it "Elliott" - a better name than "GPCC" for the companion of an extraterrestrial brown dwarf [imdb.com].
  • Wow! I must have been under a rock these past few years. I thought the only extra-solar system stellar object to be imaged with as much clarity as this photo of a Brown Dwarf (w/ companion planet) was Betelgeuse! What other stars have been resolved so that you can make out or almost make out the disk????
  • Can gas planets have eruptions and eject matter (or gas) out in space?
  • Point the Hubble at that sucker. Either we find out a bunch of neat sciency things, or we find out its Admiral Thrawns secret hidden research facility. Either way its a win!
  • And no doubt the RIAA has already sent subpoenas and cease and desist orders for evading them for so long.
    But seriously, this is spectacular. To think that there might be another planetary system within viewing distance, albeit a few small pixels is mind numbing. This is bloody brilliant.
    Any suggestions on names?
  • ..."Extrasolar planet really really confirmed, we're quite sure this time, honest".

Say "twenty-three-skiddoo" to logout.

Working...