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Oldest Known Star In the Universe Discovered 141

Posted by Soulskill from the thanks-geritol dept.
Zothecula writes "A team of astronomers at The Australian National University working on a five-year project to produce the first comprehensive digital survey of the southern sky has discovered the oldest known star in the Universe. The star dates back 13.7 billion years, only shortly after the Big Bang itself. It's also nearby (at least, from a cosmological perspective) — about 6,000 light-years away. The star is notable for the very small amount of iron it contains (abstract). The lead researcher, Stefan Keller, said, 'To make a star like our Sun, you take the basic ingredients of hydrogen and helium from the Big Bang and add an enormous amount of iron – the equivalent of about 1,000 times the Earth's mass. To make this ancient star, you need no more than an Australia-sized asteroid of iron and lots of carbon. It's a very different recipe that tells us a lot about the nature of the first stars and how they died.'"
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Oldest Known Star In the Universe Discovered More

Oldest Known Star In the Universe Discovered

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  • Comment removed (Score:5, Funny)

    by account_deleted ( 4530225 ) on Tuesday February 11, 2014 @07:21PM (#46224197)
    Comment removed based on user account deletion

  • Oldest star to date, but likely came from another (Score:5, Interesting)

    by JoshuaZ ( 1134087 ) on Tuesday February 11, 2014 @07:27PM (#46224263) Homepage
    According to TFA this star itself was likely born from the death of a genuinely primordial star (which would have started with almost nothing by hydrogen and helium). One of the upshots of this work is that some primordial stars may have produced much less iron than some models have suggested which could explain some discrepancies in the observed isotopic ratios in some old stars. According to the actual article (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature12990.html [nature.com] which may be behind a paywall) this star has an apparent visual magnitude of 14.7. This puts this star just in the limits of amateur observations. Charon has an apparent magnitude of around 15.5 http://en.wikipedia.org/wiki/Charon_(moon) [wikipedia.org] and that's been successfully imaged by amateurs (larger apparent magnitude means dimmer because astronomers are silly) http://www.universetoday.com/20351/charon-imaged-by-amateur-astronomers/ [universetoday.com] , so this star could be looked at by a dedicated amateur in the southern hemisphere.

    • Re: (Score:2, Informative)

      by infogulch ( 1838658 )

      Larger apparent magnitude means dimmer because magnitude is on a log scale, similar to pH is a log scale with a negative sign. Brightness = 2.512^(-Magnitude)

      • Yes, I know that. But it is confusing to have the negative sign there. It would work just as well without it. In contrast pH which is concentration so if you want a positive number you need a negative sign. There's no really natural reason to have a negative sign for magnitude. It works fine but frequently confuses non-astronomy people. Really these are just arbitrary conventions and I was going for a funny aside. This is definitely not the only example of a system of measurement we use which is convenient

        • It is indeed historical. The ancient Greeks divided the stars in 6 categories or magnitudes, magnitude 1 for the brightest stars to 6 for those barely visible with the naked eye. The mathematical formula only emerged later (1856 by Pogson) who defined the brightness scale by: a magnitude 1 star is 100 times brighter than a magnitude 6 star and Polaris is magnitude 2 which more or less fitted the ancient magnitude scale.

      • Isn't p negative log and therefore a different situation? At least in chem it's used a LOT, and not just with proton concentration.

        It doesnt appear the brightness magnitude has any such identifier (though im sure your correct) and therefore at least a bit more confusing.

    • http://www.thesunisiron.com/ [thesunisiron.com]

      After all, when you look at the Earth from space, you see mostly nitrogen, oxygen, and water vapor. It's always a problem to infer the interior of something from what you see on the outside (as in, you can't judge a book by its cover). The proposed LENR (Cold Fusion) physics, perhaps along with some notion of quantum decay of nuclei leading to outgassed hydrogen (my suggestion), could provide a way that a sun (or planet, including the Earth) made of mostly nickel and iron could p

      • Re:Could the sun be mostly iron? (Score:5, Insightful)

        by JoshuaZ ( 1134087 ) on Tuesday February 11, 2014 @10:06PM (#46225355) Homepage

        After all, when you look at the Earth from space, you see mostly nitrogen, oxygen, and water vapor. It's always a problem to infer the interior of something from what you see on the outside (as in, you can't judge a book by its cover). The proposed LENR (Cold Fusion) physics, perhaps along with some notion of quantum decay of nuclei leading to outgassed hydrogen (my suggestion), could provide a way that a sun (or planet, including the Earth) made of mostly nickel and iron could produce a lot of internal heat from LENR.

        No. The solar neutrino flux is almost precisely that which is proposed by models and this does let us check our models. We can also estimate the sun's density if it had an iron core. It would be much denser and it wouldn't have an easy way to prevent collapse. There's also no plausible model for anything remotely like this to form naturally. Those are just a few of the many problems with this suggestion. Thinking about ideas is good but please be aware that it is extremely unlikely that a single individual thinking on their own is going to come up with a serious problem in theories that withstood many empirical tests over the last 50 years, and even less likely to then come up with the correct hypothesis. Claiming that the sun is mostly iron isn't the same level as claiming that evolution hasn't happened, but it isn't that far off. At minimum, a glance at your website shows no predictions that would differ from standard. At minimum to be taking seriously you need to propose some test that can be done that will strongly differentiate your model from the standard explanation. Without that, there's little reason to pay attention.

      • > Could the sun be mostly iron?

        No, the sun is made of charcoal. This was clearly proved in the 1800s.

      • Re: (Score:3, Informative)

        by Kentari ( 1265084 )
        Hot fusion has been replicated many times on the surface of the Earth in: Hydrogen bombs (uncontrolled), Tokamaks, Stellerators, Z-pinch machines, Farnsworth fusors (in peoples backyard shed) and other devices. We have not managed to extract more energy from it than we put in, but we certainly replicated it.

        • Re: (Score:2)

          by Bengie ( 1121981 )
          We have recently nearly broken even with laser energy input to energy output of the fusion. What we haven't gotten yet is nearly breaking even with total energy input to total energy output, with the goal of a net extractable energy output for total energy input.

  • HA! (Score:5, Funny)

    by mythosaz ( 572040 ) on Tuesday February 11, 2014 @07:30PM (#46224305)

    The star is notable for the very small amount of iron it contains (abstract). The lead researcher, Stefan Keller, said..

    ISWYDT

  • There is a planet circling it. It's name is Z'ha'dum. Where the First One lives.

    • What do you want?

      • Never ask that question!

        • I'd like to live just long enough to be there when they cut off your head and stick it on a pike as a warning to the next ten generations that some favors come with too high a price. I want to look up into your lifeless eyes and wave like this. Can you and your associates arrange that for me, Mr. Morden?
  • The more i read stories like this, more i realize there is so much more I would like to know. Too many books not enough time lol...

    • The more i read stories like this, more i realize there is so much more I would like to know. Too many books not enough time lol...

      They won't do you much good it appears. Often I watch "How the Universe Works" (first series) to put me to sleep;
      while not a book, it's almost as good.

      They drive home the point that as soon as a star starts producing iron it's toast, in that split second it goes nova.
      The reasoning is it absorbs too much energy allowing gravity to overcome the push (outward force) of fusion.

      But it's not just "How the Universe Works" it's any article on the Sun will tell you the same thing.

      Finally figure you have a handle on

  • Lead researcher, Stefan Keller... (Score:3, Funny)

    by Anonymous Coward on Tuesday February 11, 2014 @07:41PM (#46224407)

    If he is a lead researcher, what does he know about iron? I found in my old astronomy textbook a list of the elements that make-up the top 99.99997% of the mass of the sun. Lead is not in that list. Why have a lead expert involved instead of an iron researcher involved? The reason we're interested in this star is because of the low mass of iron, not lead.

  • Astronomy: Astrology for Physicists (Score:4, Interesting)

    by musmax ( 1029830 ) on Tuesday February 11, 2014 @08:00PM (#46224557)
    I don't get it. If it so old it should be an ember by now, or does it still radiate ? If its only 6k ly from here then it still radiates right ? Also, if it is so old it should have 'expanded' away enormously.... or not. Its like finding a live dinosaur in your back yard.

    • Re:Astronomy: Astrology for Physicists (Score:5, Informative)

      by JoshuaZ ( 1134087 ) on Tuesday February 11, 2014 @08:08PM (#46224627) Homepage
      Small stars can live a very long-time. For example a red dwarf that is a tenth the size of the sun can likely keep burning for trillions of years. http://en.wikipedia.org/wiki/Red_dwarf [wikipedia.org]. A star of the size discussed here easily has billions of years more to it lifespan.

      • Look to the post above.

        Large stars have high interior pressure. Fusion rates are high. The stars burn out fast.

        Small stars have much lower internal pressure. Fusion rates are low. The stars can last a long, long, long time.

      • But Red Dwarf was only 3 million years old when Dave Lister woke up.

    • Re: (Score:1)

      by Anonymous Coward

      That's actually a really fucking good point. I don't understand that either. If it's 13 billion years old, how the fuck is it still going? If it were 13 billion light years away or some shit, then yeah I'd get it. But 6,000???? Can someone with some legit knowledge explain this?

      • Re:Astronomy: Astrology for Physicists (Score:5, Funny)

        by avgjoe62 ( 558860 ) on Tuesday February 11, 2014 @08:34PM (#46224799)
        It's an LED star, not an incandescent...

      • Re:Astronomy: Astrology for Physicists (Score:5, Interesting)

        by jfdavis668 ( 1414919 ) on Tuesday February 11, 2014 @09:08PM (#46225053)
        Very small stars are like small cars, very fuel efficient. Large stars have a higher pressure in the core, and fusion runs faster. The core is so dense it does not convect. The amount of fuel in the core is all the star has to fuse. A red dwarf is fully convective. All the gas in the star drops down into the core, heats up, and raises back to the surface. The star can therefore fuse all the gas in the entire star, not just the gas in the core. So, it uses all its potential fuel, very conservatively. Therefore, it can last a long time.

      • If it were 13 billion light years away or some shit, then yeah I'd get it. But 6,000???? Can someone with some legit knowledge explain this?

        There is no law that I'm aware of that states that objects closer to us have to be somehow newer. The Big Bang happened all around us - yes, right there where you are standing. And everywhere else in the universe. So the oldest thing in the universe may very well be very close to us. In fact, all the sub-atomic particles that you and I are made of are as old as the universe, so that statement is trivially true.

        This intuition that old things are very far away probably originates from the fact that when we lo

      • Why the fuck would you expect it not to be still going?

      • The phrasing is a bit misleading. The star was 6000 light-years away when it first emitted the light, but the empty space between stars (and galaxies, now) has been expanding continuously (but at a nonconstant rate) since then. Imagine a car driving along a rubber sheet that's stretching. The sheet *starts* 6000 miles long and the car drives at one mile per hour, but since the sheet is growing as the car drives along it's 13.7 billion years long by the time the car reaches the other end.

        So we're seeing the

        • Oops, correction to the car analogy: The rubber sheet is 6000 miles long when the car starts driving, is 46.6 billion miles long when the car stops driving, and the car itself thinks it has driven 13.7 billion miles relative to the sheet. (If space behind you expands, you don't have to redrive that extra distance.) Replace miles with light-years and we have a description of the photon traveling from this star to the Milky Way galaxy: they started 6000 light-years apart, they ended 46.6 billion light-years a

        • I'm sorry, but what you've said there isn't correct in this case. As far as I can tell from TFA, we are not talking about a 13.7 billion year old image of something very far away (as is usually the case with this sort of story)- we're talking about a star that is still going, and is literally, right now, 6000 ly away. That is to say, the image we are seeing now is of the star as it was 6000 years ago. The image we are seeing now is NOT as the star was shortly after the Big Bang, it's of a star that was arou

    • Re: (Score:1)

      by Anonymous Coward

      I don't get it. If it so old it should be an ember by now, or does it still radiate ? If its only 6k ly from here then it still radiates right ? Also, if it is so old it should have 'expanded' away enormously.... or not.

      Its like finding a live dinosaur in your back yard.

      You can have stars that last 20 billion years (we assume), so 13 billion odd is fine.

      The other point you bring up is more interesting. The 6k light years away is interesting. It may have been a very near star 10 billion years ago, near the suns predecessor or its predecessor. But space was smaller back then, everyone was friends back then.

    • Regarding expansion, as I understand it, the effects on objects within something as small as a galaxy are insignificant compared to the force of gravity holding the galaxy together.

      The greater the distance between two objects, the greater the effect of expansion; and so it does become significant when comparing two distant galaxies.

    • If it so old it should be an ember by now, or does it still radiate ?

      If it didn't radiate they probably wouldn't have noticed it.

    • I don't get it. If it so old it should be an ember by now, or does it still radiate ? If its only 6k ly from here then it still radiates right ?

      We won't know if it still radiates in 2014 until the year 8014.

  • the first stars don't have elements heavier elements generally thought to be created in supernovae, and large stars?

    Who knew?

    except this is so fucking basic astronomy knowledge they teach it to first year university students, with no knowledge of either astronomy or physics

    Good grief charlie brown.
    • That's not the "news" part, in the same way an article about a plane crash is not "news" of gravity. Not everyone on the planet has listened to Sagan and his "we are star stuff" speech, some people still need to be taught (including first year astronomy students). A rehashing of "basic knowlege" helps these readers understand how the astronomers determined the age of the star in question, after all the stars age is the "news" part.

  • I mean, how do we know it's still there? It could have assploded yesterday and we won't know it for 6000 years.

  • ...that there's only a finite number of stars in the observable universe, so eventually they'll exhaustively find the oldest one of the lot, provided they can see it, and accurately verify its age, and tick off all the other candidates so as to ensure they have the correct answer. Then one has to ask what real-world survival problem will ever be aided by such research?

    • Knowing which is the oldest object in the world is like doing archaeology.

      Looking at old objects we humans can determine more about how the world looked like when the object was created. The materials that was used. The way the object was formed.

      It's important information that helps give a greater understanding of our universe and how it was created and the condition that then existed.

    • ...that there's only a finite number of stars in the observable universe, so eventually they'll exhaustively find the oldest one of the lot, provided they can see it, and accurately verify its age, and tick off all the other candidates so as to ensure they have the correct answer. Then one has to ask what real-world survival problem will ever be aided by such research?

      Studying old stars will help us understand how our universe began. We will learn about the fundamental forces in nature, how the big bang happend, what is the relation between gravity and quantum mechanics. If we understand that, the posibillities are endless - warping spacetime, FTL travel, unlimited energy sources etc. That could solve a lots of real-world survival problems we have today, certainly more than funds spent on wars or propaganda.

  • "......discovered the oldest known star in the Universe"

    Thanks submitter for using a scientifically accurate description rather like in TFA where they say it's the oldest star in the Universe..

  • Wouldn't that be oldest unknown star in the universe discovered? One would think that if it was already known, it wouldn't be much of a discovery!

  • Of course, all these ages and distances assume one huge piece of information has always been constant: speed of light. What if it hasn't? Has anyone bothered to verify through these 6k light years that the light was always traveling at the same speed ?
  • With the right technology, would it be possible to artificially change a stars apparent age, e.g. by siphoning off the heavier atoms in its atmosphere with magnetic fields?

    Artificially modified stars, if they exist, could be a way to detect extraterrestrial intelligence over truly vast distances.

  • Finally, we have proof that the creationists are wrong! Alert Mr. Ham!
  • The age of the universe is according to Wikipedia [wikipedia.org]

    "In physical cosmology, the age of the universe is the time elapsed since the Big Bang. The best measurement of the age of the universe is 13.798±0.037 billion years ((13.798±0.037)×109 years or (4.354±0.012)×1017 seconds) within the Lambda-CDM concordance model.[1][2] The uncertainty of 37 million years has been obtained by the agreement of a number of scientific research projects, such as microwave background radiation measuremen

    • the Sun is only 4.5 billion years old; the Sun has made just over 18 laps.

      Why do you think that "sounds little", and what physical measurement would imply older universe (we have several that point to about 14 billion years)

      • It does sound "very little"- but that's just a cool realisation to make. It's easy to think of everything in the universe being very permanent and enduring- and a little shocking to realise that even mega-scale structures of the universe are only fleeting or are quite young.

        Considering how long the universe's processes are expected to go on for (star formation might be expected to end roughly 100 trillion years from now), we are currently existing in the extremely early days of the universe. The universe ha

        • even after 100 trillion years, occassional collisions will make short lived stars if certain boundary conditions are met: carbon stars and helium-fusion stars. Sometimes brown dwarfs will collide to make a red dwarf star that can last 10 trillion years. so life may be possible at various times even after the universe's main star formation period ends. Interesting wikipedia articles about various models and speculations: http://en.wikipedia.org/wiki/F... [wikipedia.org]

          • One other reason I think this sounds "very little" is that heavy elements need a successive series of star formations to be formed. So, 18 laps for the Sun since the dawn of the universe, as Patch86 mentioned, also sounds too few. No, I don't have any better hypothesis. Yet, perhaps we are seeing a logarithmically contracted time scale once we look back in time and that such a phenomenon produce these effects.
            • Sorry, it wasn't Patch86 but you iggymanz who made that reflection

            • Our Sun did not exist at the dawn of the Universe, the Universe has existed three times as long as the Sun has. The Sun and solar system are made of the remains of other stars that built up the heavy elements.

  • I haven't read the abstract, I'm sure the journal article is behind a paywall. The Idea here is that the star is old because it is "Metal" poor. In Stellar Evolution parlance "Metal" refers to anything heavier, any atom heavier, than helium. Most of the stars fuse hydrogen to heavier elements as they evolve. Evolution stops when the binding energy per nucleon reaches a maximun at around Fe or Ni. Most of the element abundances are greater up to mass = 56 and although heavier elements do exist, they are far

    • I went to the abstract. It refers to four low-mass stars with some "metals" but almost no Iron. So the reasoning is that these stars were seeded by metals from low-mass novas that didn't make the iron one sees in current supernovae. This is intrepeted as a situation of first generation stars in the earliest galaxies, hence the inference of great age. The line of reasoning might not stand up if it is revealed that these stars to not reveal all their metals in their atmospheric absorption spectra, they don't

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