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Space

Euclid Telescope Spies Rogue Planets Floating Free In Milky Way (theguardian.com) 53

Posted by BeauHD from the hide-and-seek dept.
Using the Euclid space telescope, astronomers have discovered dozens of rogue planets drifting without stars in the Orion nebula. The Guardian reports: The European Space Agency (Esa) launched the $1 billion observatory last summer on a six-year mission to create a 3D map of the cosmos. Armed with its images, scientists hope to understand more about the mysterious 95% of the universe that is unexplained. The first wave of scientific results come from only 24 hours of observations, which revealed 11m objects in visible light and 5m in infrared. Along with the rogue planets, the researchers describe new star clusters, dwarf galaxies and very distant, bright galaxies from the first billion years of the universe.

A flurry of new images from the same observations are the largest ever taken in space and demonstrate the stunning wide-field views that astronomers can expect from Euclid in the coming years. Among those released on Thursday is a breathtaking image of Messier 78, a vibrant star nursery shrouded in interstellar dust, that reveals complex filaments of gas and dust in unprecedented detail. One of the newly released images shows Abell 2390, a giant conglomeration of more than 50,000 Milky Way-like galaxies. Such galaxy clusters contain up to 10 trillion times as much mass as the sun, much of which is believed to be elusive dark matter. Another image of the Abell 2764 galaxy cluster reveals hundreds of galaxies orbiting within a halo of dark matter.

Other images capture NGC 6744, one of the largest spiral galaxies in the nearby universe, and the Dorado group of galaxies, where evolving and merging galaxies produce shell-like structures and vast, curving tidal tails. The rogue planets spotted by Euclid are about 3m years old, making them youngsters on the cosmic scale. They are at least four times as big as Jupiter and were detected thanks to the warmth they emit. Astronomers know they are free-floating because they are so far away from the nearest stars. The celestial strays are destined to drift through the galaxy unless they encounter a star that pulls them into orbit.
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Euclid Telescope Spies Rogue Planets Floating Free In Milky Way More

Euclid Telescope Spies Rogue Planets Floating Free In Milky Way

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  • So now suddenly we can 'see' dark matter? Really?

    Sensationalist trash article but kudos to the ESA for the real science work they're doing.

    • Re:Halo of dark matter? (Score:4, Informative)

      by Mr. Dollar Ton ( 5495648 ) on Friday May 24, 2024 @06:02AM (#64495581)

      You can be sure that a couple of planets don't constitute close to 85% of the stuff that we can't see except by its gravity described usually as "dark matter". The MACHO hypothesis [wikipedia.org] has been tested and shown not to work.

      • I'm sure they don't add up to that much but crap article refers to a halo of something that can't be seen.

        I saw after I hit submit this was a guardian article, It all made sense at that point.

        • Re: (Score:3)

          by HiThere ( 15173 )

          I expect there actually IS a halo of stuff that can't be seen. And that's not what the term "dark matter" means. "Dark matter" refers to non-baryonic matter that (essentially) only interacts via gravitational interactions. Wandering planets are a totally different kind of thing, and many folk have previously called them "rogue planets", even though I don't like the term. I've occasionally called them "free planets" because they aren't bound to any particular star.

          • "Another image of the Abell 2764 galaxy cluster reveals hundreds of galaxies orbiting within a halo of dark matter."

            Doesn't that imply that you can see the dark matter halo? Were they being scientific when they wrote that, or were they hallucinating a theory into an image, much as biologists counded 24 chromosomes in the same photographs that we now count 23?

            • No, it means that you can see a difference in the visible matter distribution, the velocities of the pieces that constitute it or the power of the "gravity lens" compared to what is expected by our current ideas about the laws of physics, established over a long period of time from many different experiments.

              In other words, there is indirect evidence for the presence of "dark matter", not direct observations.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      So now suddenly we can 'see' dark matter? Really?

      You should probably stick to the words actually in the summary and article. The made up words from your imagination aren't helping you :P

      Yes, we can see stars. Yes, we can see the heat from this planet, by way of IR.

      No, we can't see dark matter.
      Yes, we CAN detect it. Detect != see

    • So now suddenly we can 'see' dark matter? Really?

      No. We have never been able to "see" dark matter not even now. There is a new image of galaxy cluster Abell 2764. It is suggested to have a halo of dark matter based on the stars that can be seen..

    • So now suddenly we can 'see' dark matter? Really?

      Bear in mind that the whole idea of dark matter is a handwave concocted to make our current picture of cosmology work out mathematically. We observed that at today's rate of universe expansion there seemed to be a large amount of 'missing mass' in the universe. If we assume the existence of some large amount of matter that we can't see, then our existing conception of reality works out. At the end of the nineteenth century, physicists assumed the existence of 'luminiferous aether' to make their own concepti

      • Re: (Score:3)

        by XXongo ( 3986865 )

        So now suddenly we can 'see' dark matter? Really?

        Bear in mind that the whole idea of dark matter is a handwave concocted to make our current picture of cosmology work out mathematically.

        Sort of. The idea that small perturbations in orbits that are not explainable by the things we can see are likely caused by things that we don't see had a long history, starting in 1781 with the discovery of Neptune based on the fact that the orbit of Uranus was slightly different from what would be predicted from the gravitational effects of all the known planets.

        When we can't fully explain a trajectory by the things we can see, the idea that it's due to the forces from things we can't see is always the fi

      • But suppose that there is just a really large number of rogue planets out there. The ones we can see now are subject to observation bias: we can only see very large ones, and against a bright nebular background. How many smaller ones might be floating around in the dark?

        I would assume that physicists have already accounted for that. 95% of the universe is unexplained means that it cannot be explained by rogue planets. The number of these planets would have to be so large that most of the universe is made up of rogue planets instead of stars which can be seen. That also does not fit into the Big Bang theory on how matter is distributed. It is contracted by the mass distribution confirmed by multiple cosmic background radiation surveys.

      • That is not what dark matter is about.

        Galaxies rotate faster than it is plausible, considering their estimated mass.

        So there is some extra mass hidden in them, that makes them rotate so fast: we do not know what that is, so some scientist coined the term "dark matter" ... dark mass would perhaps been better - but the word dark makes it all so spooky that people like you mix it up.

        The concept behind the observed "to fast" or probably even accelerating expansion of the universe, is called: "dark energy"

      • Re: (Score:2)

        by cusco ( 717999 )

        For the 'missing matter' problem to be explained by rouge planets there would have to be so many of them that they're regularly eclipsing stars/galaxies all over the place and enough would have passed close to our Solar System to have perturbed the orbits of the outer planets. We don't see either of those things, so rogue planets aren't the explanation.

      • How many smaller ones might be floating around in the dark?

        Not enough to account for the missing mass.

    • So now suddenly we can 'see' dark matter? Really?

      If you read the text, what it says is that what we see is an "image of the Abell 2764 galaxy cluster reveals hundreds of galaxies". So, no, we con't see dark matter. The orbits of the galaxies in the cluster reveals the presence of dark matter (or, if you prefer, provides possible evidence of new gravitational physics), but no, we don't see dark matter, not in the visible, not in the infrared.

  • They are at least four times as big as Jupiter and were detected thanks to the warmth they emit. Astronomers know they are free-floating because they are so far away from the nearest stars.

    If these planets are “free-floating” and unbound from any star (a.k.a. Sun), then I’m just curious as a layman; if they were detected because of the warmth they emit, what is the heat source that is so strong?

    Don’t we often refer to ‘planets’ that warm, dying stars?

    • Re:Dying stars? (Score:5, Informative)

      by pjt33 ( 739471 ) on Friday May 24, 2024 @06:59AM (#64495663)

      Jupiter also emits more heat than it receives from the Sun, but it's not fusing hydrogen so it doesn't qualify as a star. It's due to the Kelvin-Helmholtz mechanism [wikipedia.org]: in summary, it's collapsing under its own mass and converting gravitational potential energy into heat.

    • Re:Dying stars? (Score:5, Informative)

      by AleRunner ( 4556245 ) on Friday May 24, 2024 @07:39AM (#64495729)

      Probably mostly what pjt33 says, but the Earth gets a noticeable amount of heat from internal decay of radio-isotopes [wikipedia.org]. Any planet with a rocky core would have some of the same. That would be less important in a gas giant though since it's mostly made up of basic hydrogen which wouldn't decay as a radio-isotope so the heat from the decay of other elements would be more dissipated.

    • If these planets are “free-floating” and unbound from any star (a.k.a. Sun), then I’m just curious as a layman; if they were detected because of the warmth they emit, what is the heat source that is so strong?

      What warmth can these planets emit? You assume that this rogue planet is like Earth with an active thermal core. They could be more like Pluto and be just a rock floating in space. Also while it is not bound to a star, that does not mean that nearby stars will drown out any IR signal that it could emit.

  • Didn't anyone see star wars? They are giant spaceships (death stars). And of course they are warm. Those ships need a modern fusion power source.
  • I much prefer wizard planets, chaos warrior planets, or even barbarian planets.
  • Comment removed based on user account deletion
    • Mavity.

    • Re: (Score:2)

      by HiThere ( 15173 )

      I'm rather sure that was an interpolation by the journalist. That's not what cosmologists mean by the term "dark matter".

    • Re:hmm (Score:4, Informative)

      by UnknowingFool ( 672806 ) on Friday May 24, 2024 @09:20AM (#64495979)

      how are we so sure about the matter/dark matter content of the universe if 95% is unexplained?

      Just over a hundred years of observations [youtube.com], that's all. The first person to suggest it existed based on observations was Lord Kelvin in 1884. People who are not physicists and astronomers generally assume that dark matter is a new thing when it is not. In the realm of mainstream media, the general public is learning about dark matter recently.

      Technically, 95% of the universe is dark matter(27%) and dark energy (68%).

      • Comment removed based on user account deletion

        • ugh, doctor becky - id rather be forced to watch michio kaku

          Michio Kaku [youtube.com] says that only a tiny percentage (5%) of the universe is normal matter and energy. 95% is dark matter and dark energy. Does that satisfy your appeal to authority?

          but Im talking about the "observable matter cannot account for the gravity we see".... it seems like we dont have an accurate account of matter in the first place?

          You literally described dark matter but somehow refuse to use the term. Dark matter is nonbaryonic matter that is only detected by the presence of gravity but does not react in other ways like to light. That's like me saying I don't have a Toyota "truck". My Tacoma is just a coupe that is higher than other passenger cars and it has a f

          • Comment removed based on user account deletion

            • jeez il put it into plain english

              1) This is in English. 2) Terminology in a particular field was created by people in that field. In computer science, the term "hard drive" could be known as as "spinning platters of mostly aluminum covered in iron or cobalt." Most people use the term "hard drive".

              how accurate is the current estimate of how much baryonic matter there is in the universe?

              By accurate are you asking for the error measurements in each and every observation over the last hundred years? They are listed in each paper. Or do you mean that overall, we have over a hundred years of observations from dozens of papers in Dr B

            • The 5% number (as well as the dark matter and dark energy numbers) comes from the Lambda-CDM model [wikipedia.org], which is fit using observations of the cosmic microwave background anisotropy and supernovae redshift among others. It's an interesting time for cosmology. Lambda-CDM is the best model around, some observations seem to indicate there may be some problems with it.
  • put it in the same orbit around the sun as earth is only on the opposite side of the sun as earth is, terraform it and make it habitable,

    /sci-fi mode

  • If thy don't orbit a star.
    Hell, they'd have to include Pluto again if they were designated 'planets'.

    • Thank a particular organization for a slew of bad renamings. It's as if a pig was different based on if it lives in a barn or a yard. And it's not their only weird decision: they eg. redefined "north" based on alignment towards Earth's orbit rather than spin. That definition is useless outside the Solar System and even for some Solar System bodies that cross the boundary or have complex orbits.

      And they did it before, too: IAU got created in 1919, and until 1920 the definition of planet didn't exclude pla

      • It's as if a pig was different based on if it lives in a barn or a yard.

        Is that... wrong? If defining it in relation to something else is categorically wrong, why do you call a free-floating mass in space a 'planet' instead of a 'moon'?

  • So you're cruising along at warp 8, then where'd that come from Wham!

  • I, for one welcome our lost would-be new overlords.

    Or, well, maybe I would if they could find us . . .

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