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The Universe Has 20 Times More Galaxies Than We Thought (gizmodo.com) 258

A new study by a team of international astronomers has produced some astounding results: they concluded that the universe contains at least two trillion galaxies -- as much as 20 times more than previously thought. The study adds that 90 percent of all galaxies are hidden from us. This hidden portion can't be seen even with our most powerful telescopes. Gizmodo adds: Consequently, this means we also have to update the number of stars in the observable universe, which now numbers around 700 sextillion (that's a 7 with 23 zeros behind it, or 700 thousand billion billion). And that's just within the observable universe. Because the cosmos emerged some 13.8 billion years ago, we're only able to observe objects up to a certain distance from Earth. Anything outside this "Hubble Bubble" is invisible to us because the light from these distant objects simply haven't had enough time to reach us. It's difficult -- if not impossible -- to know how many galaxies reside outside this cosmological blind spot.
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The Universe Has 20 Times More Galaxies Than We Thought

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  • No. (Score:3, Funny)

    by Anonymous Coward on Thursday October 13, 2016 @03:14PM (#53071763)

    The Universe Has 20 Times More Galaxies Than We Thought

    20 times more than YOU thought, perhaps, but not me. I hadn't thought.

  • by QUASAR_FREAK ( 1898426 ) on Thursday October 13, 2016 @03:15PM (#53071781)
    Does this change then the need for dark matter? or it doesn't matter? xD
    • No, and the summary gets it wrong, too. In the early universe the galaxies were smaller, so there were more of them. The number of stars and the mass of dark matter hasn't changed.

    • by suutar ( 1860506 ) on Thursday October 13, 2016 @03:26PM (#53071869)

      as far as I can tell it doesn't matter - dark matter is invoked to explain why individual galaxies don't fall apart, because the mass we can see doesn't seem to be enough to keep it together at the rate they spin; having more galaxies doesn't change that.

      (I find it amusing that dark matter is handwaving why big things don't fly apart and dark energy is handwaving why bigger things do :) But I'm weird :)

      • by painandgreed ( 692585 ) on Thursday October 13, 2016 @06:36PM (#53073031)

        (I find it amusing that dark matter is handwaving why big things don't fly apart and dark energy is handwaving why bigger things do :) But I'm weird :)

        Galactic rotation curves was just the first bit of observational evidence that we saw over 80 years ago. Since then, every other explaination has been shown not to be the case. Since then, there have been many other observed evidence such as gravitational lensing, fluctuations in the CBR, etc. which is all under Observational Evidence under the Dark Matter Wikipedia page. All have been pointing more and more towards matter than only interacts via gravity, while all other competing theories fail to explain other observations. Furthermore, it tends to be called dark matter, and dark energy, energy, because they end up with unknowns that have specific units, and when those units are those of mass or energy, they get called mass and energy.

        • by suutar ( 1860506 )

          Ah, cool. I was pretty sure that they had other reasons besides galactic spin by now, but I didn't realize that the units worked out that way. Thanks!

    • by gtall ( 79522 )

      No, we still need dark matter or a lot of our physics theory is bunk. The bunk bit needs to be avoided.

  • Not sure why they have the digression into the non-observable universe. The 90% refers to the observable universe only.
  • Drake Equation.... (Score:4, Insightful)

    by tekrat ( 242117 ) on Thursday October 13, 2016 @03:18PM (#53071815) Homepage Journal

    So, how does this affect the Drake Equation? Even if we assume a very, very low percentage of extraterrestrial life and even a lower percentage of *intelligent* extraterrestrial life, we're still looking at "billions and billions" (sorry Carl) of potential intelligent species out there, we just can't seem to contact them though due to the vast distances involved.

    Too bad really. Until we can come up with some way of cheating physics, we are stuck in this solar system for the foreseeable future.

    • by Quirkz ( 1206400 ) <ross @ q u irkz.com> on Thursday October 13, 2016 @03:41PM (#53071991) Homepage

      Short answer is, it multiplies the number by 20. Drake equation is just a string of multipliers. One of them reflects the total number of worlds. 20x more galaxies is 20x more worlds. (Assuming the extra 19 galaxies are of equivalent size.)

      • "Assuming the extra 19 galaxies are of equivalent size." They're not, at least not equivalent to the one. Apparently the astronomers think the large nearby galaxies we see near us are the result of mergers of much smaller ones over time. In other words, the old galaxies--those 19--are much smaller (perhaps 1/20th, IIUC).

    • by cfalcon ( 779563 ) on Thursday October 13, 2016 @04:02PM (#53072129)

      It doesn't. The Drake equation only applies to the Milky Way. If you want to expand the Drake equation to the entirety of the universe, you take whatever number you get from the Drake equation, and multiply by the number of galaxies in the universe, which keeps being revised upwards with more detection. So at minimum, you are looking at whatever your Drake equation is times a hundred billion.

  • by wwalker ( 159341 ) on Thursday October 13, 2016 @03:20PM (#53071821) Journal

    Does this imply that the universe is expanding faster than the speed of light? Wouldn't that be a contradiction of the speed of light being the fastest speed you can travel at? Can someone who read the article shed some light on this? :)

    • If I'm traveling at the speed of light in one direction and something else is traveling at the speed of light in the opposite direction, how long is it before it's light reaches me?
      • Re:Wait (Score:4, Interesting)

        by thorndt ( 814642 ) on Thursday October 13, 2016 @04:00PM (#53072119)

        Well....let's change that to something that is physically possible.

        If you were travelling 99.99% the speed of light in one direction, and something else, say 1 light year away, was travelling in the opposite direction at 99.99% the speed of light. From YOUR perspective in the first ship, the light from the other ship would take....wait for it.....1 year.

        Spacetime stretches and squishes based on your speed. That's WHY time dilation occurs.

    • Re:Wait (Score:5, Informative)

      by Plus1Entropy ( 4481723 ) on Thursday October 13, 2016 @03:31PM (#53071909)

      The speed of light limits how fast you can travel through space. The expansion of the universe is due to space itself expanding, and there is no limit (as far as we know) to how fast this can happen.

    • by suutar ( 1860506 )

      The "inflationary period" theory does indicate that space expanded at rates faster than light would be able to travel (for a while - the description I read of the theory [wikipedia.org] says it was done by 10^-32 seconds after the big bang and that in that time the universe expanded by 10^26 or more), but it seems that since it was space expanding and not matter moving through space, it's not considered a contradiction - like saying that a boat with a top speed of 10 knots relative to the water could be carried by a fast c

    • It's bigger than it looks.

      The current scientific view is that the big bang exploded the universe out far faster than the speed of light. They think it got to the size we see within a trillionth of a second.

    • The universe can expand faster than the speed of light with out violating any physical laws. See Inflation: https://en.wikipedia.org/wiki/... [wikipedia.org]

      But you will probably need someone smarter than me to explain it to you...

      Ill give it a try but I might be quite wrong: During inflation, even though the universe was expanding faster than the speed of light, no information was traveling faster than light, no causal effects traveling faster than light, and no laws broken.

      Now I'll just wait for a real scientist to
    • by idji ( 984038 )
      The universe can expand faster than the speed of light. As space expands the space between locations grows. Since no object is moving faster than the speed of light, this doesn't break relativity. If you see something go left at 0.8c and something go right at 0.8c, they are going apart from each other at 1.6c in your frame of reference, but not in their frames of reference, because they have very different times. But you won't see objects moving at 1.6c, you just see locations receding. If a line of people
    • The expansion of the universe doesn't involve anything travelling - it happens via the addition of more space in between all the objects. Everything ends up further away from everything else, but nothing actually moved through space. The amount of new distance that gets added then depends on how much distance is already there, so if you consider something far enough away, the amount of new distance appearing between you and it is more than light can travel across in the same time period (so any light trying

    • That's the fastest that a mass-less particle can travel through space, not how fast the universe itself can expand.

      We don't even know what the medium is outside of the universe (if there even is anything) and even then, our speed of light "speed limit" might not apply there.

  • Even if we could travel at the speed of light, we probably couldn't even catch/contact many of those near the edge of detection, yet still visible.

    Due to accelerating expansion, they would be moving too fast to catch by the time we got close.

    Thus, they are effectively shut off from us such that we perhaps should consider them just shadows of the past, fossils, rather than tangible things. If they launch ET or messages from ET, they better do it soon, or should have already done it, if they want us to see.

    No

  • Read The Fine Paper (Score:5, Informative)

    by Netdoctor ( 95217 ) on Thursday October 13, 2016 @03:37PM (#53071951)

    So I had to click around awhile, but here's the actual paper:

    http://www.spacetelescope.org/... [spacetelescope.org]

    For some of us, it makes a huge difference if we're reading the actual paper, or trying to understand the watered-down version on a click-bait site.

  • Every time I read news like this I feel like I've just entered the Total Perspective Vortex http://hitchhikers.wikia.com/w... [wikia.com]. For those that don't know (shame!), this invention, originally created by Trin Tragula as a way to get back at his wife (who was always telling him to get a "sense of proportion"), is now used as a torture and (in effect) killing device on the planet Frogstar B. The prospective victim of the TPV is placed within a small chamber wherein is displayed a model of the entire universe - t

  • If there is much more mass beyond the observable universe won't that help explain why the observable universe is expanding faster than it should (based on the mass of the observable universe)?

  • To clarify, because the summary makes a mess of it, the twenty times more galaxies they are talking about are within the observable universe.

    The stuff about galaxies we can never see because they're outside the OU was just a bit of colour at the end of the article.

  • God put those extra galaxies there to fool unbelievers. /s
  • The Universe Has 20 Times More Galaxies Than We Thought

    Just when I finished my bucket list.

  • Comment removed based on user account deletion
  • "Consequently, this means we also have to update the number of stars in the observable universe"

    If these stars are not observable, why do we have to update the number of observable stars?

  • Then why the tell did Samsung just issue a profit warning?

  • This line fascinates me

    "Because the cosmos emerged some 13.8 billion years ago, we're only able to observe objects up to a certain distance from Earth. Anything outside this "Hubble Bubble" is invisible to us because the light from these distant objects simply haven't had enough time to reach us."

    The light has been traveling for 13.8 billion years and it still hasn't reached us. That is amazing.
  • So, if the Universe has 20 times as many galaxies, and so, presumably, 20 times as much normal matter, then the estimate that the Universe is only 4% normal matter jumps to 80% normal matter, and a *lot* less dark matter, right?

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