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70,000,000,000,000,000,000,000 Stars Out There

ChopsMIDI writes "Ever wanted to wish upon a star? Well, you have 70,000 million million million to choose from. That's the total number of stars in the known universe, according to a study by Australian astronomers. It's also about 10 times as many stars as grains of sand on all the world's beaches and deserts."

35 of 195 comments (clear)

  1. and all the media seems interested in by Enrico+Pulatzo · · Score: 4, Funny

    are J-Lo and Ben Affleck...bummer

  2. seti@homing it up by sirmikester · · Score: 3, Funny

    [quote]Asked if he believed the huge scale of the universe meant there was intelligent life out there somewhere, he told the paper.

    "Seventy thousand million million million is a big number ... it's inevitable."[/quote]

    Good thing i'm keeping my seti@home client running all the time... we're bound to find something sometime!

    --
    In linux libertas
    1. Re:seti@homing it up by ThorGod · · Score: 5, Informative

      Ahh yes, but the space-time window in which we're viewing is very, very, very, very, very, very (get the picture?) recent and equally narrow.

      If you're into this subject, I suggest reading "Hyperspace" by Michio Kaku. Good book, and he's got at least a chapter on the statistical analysis of the existance of life in the Universe. Very good book all around :)

      --
      PS: I don't reply to ACs.
    2. Re:seti@homing it up by i_am_nitrogen · · Score: 5, Interesting

      I bought Hyperspace used and it is indeed a very thought provoking reading. There are probably some newer theories that aren't discussed in the book, but it's still pretty decent popular science. One thing I didn't like about it is in some parts the author seems to try to aggressively imply that there is proof that God doesn't exist, when of course, such proof is currently impossible to obtain using current methods and technology, as is proof that God does exist.

      It's quite similar to what SCO is trying to do. Some scientists and others apparently believed that if they say it loud enough long enough, eventually it will be accepted as truth. Guess what: in large part, it worked. In reality, there cannot be a proof for everyone that God does or does not exist. The only way to find out is to look for yourself.

  3. IPv8? by m0rph3us0 · · Score: 4, Funny

    Does this mean within the next few eons we may have to transition to a 256 bit IP space or will IPv6 be enough?

    1. Re:IPv8? by Danse · · Score: 3, Funny

      then again, latency times in terms of hundreds of years may be a big turnoff for some web surfers.

      Yeah, playing Quake MDXXV will be a bitch with that kinda lag.

      --
      It's not enough to bash in heads, you've got to bash in minds. - Captain Hammer
    2. Re:IPv8? by Captain+Nitpick · · Score: 4, Funny
      Does this mean within the next few eons we may have to transition to a 256 bit IP space or will IPv6 be enough?

      In the long-standing tradition of dorks, I'm going to take your joke question seriously and answer it.

      If I'm counting zeroes correctly, we've got 7e22 stars to deal with. Base 2 log of 7e22 is 75.8898. Since having fractional bits isn't really feasible, that gets rounded up to 76.

      IPv6 uses 128 bit addresses, so subtracting off the 76 bits for specifying the star leaves us with 52 bits to play with. 2^52 gives us 4.5e15 addresses, which is roughly a million times more addresses than IPv4's 32 bits allow.

      In short, IPv6 does have a big enough address space to cover the visible universe, as long as you're not trying to assign individual IP addresses to trillions of nanobots.

      --
      But then again, I could be wrong.
  4. I've figured out the population of the world. by bons · · Score: 2, Insightful

    By calculating the population of my neighborhood and assuming that my neighborhood has average distribution...

    From the article:
    That number was then multiplied by the number of similar sized strips needed to cover the entire sky, Driver said, and then multiplied again out to the edge of the visible universe.

    I wonder if this sort of "science" is how hardware manufacturers get their numbers?

    1. Re:I've figured out the population of the world. by Anonymous Coward · · Score: 3, Insightful

      The method is actually fairly accurate - the distribution of galaxies and their density is sufficiently uniform to provide a number that shouldn't be off by more than 7-8%.

      A similar approach was used long ago to (quite successfully) estimate the number of galaxies in the universe before we had the technology to measure signals from the farthest ones directly (which was done at first when we had gamma-class radio telescopes).

      It's really more clever than it sounds. You just have to take a few mathematical parameters into the equation (for example, Einstein spacetime curvature might distort radiation quantitiy when passing particularly dense areas of space).

    2. Re:I've figured out the population of the world. by Bootsy+Collins · · Score: 4, Insightful

      By calculating the population of my neighborhood and assuming that my neighborhood has average distribution...

      From the article:
      > That number was then multiplied by the number of similar sized strips
      > needed to cover the entire sky, Driver said, and then multiplied again
      > out to the edge of the visible universe.

      I wonder if this sort of "science" is how hardware manufacturers get their numbers?

      Be careful. Do you have a reason to believe that your neighborhood is typical? Do you have data indicating such?

      The astronomers in question didn't use such an approach because they're idiots; they used such an approach because we already have a heck of a lot of data about the galaxy distribution. The RMS (fractional) fluctuation in galaxy number count in a random volume the size of the one they surveyed is expected to be tiny; and it's expected to be tiny because of surveys we've already done which indicate such a convergence towards homogeneity as scale increases.

  5. I don't believe it... by RALE007 · · Score: 4, Funny
    ...and intend to disprove this claim.

    1, 2, 3, 4, 5...

    --
    Beware blue cats moving at .99c
  6. Couldn't it be said as... by TheWanderingHermit · · Score: 2, Informative

    70 sextillion? Or did I miscount 000's?

  7. My property! by Drakker · · Score: 4, Funny

    Star number 65 000 561 002 023 162 and all its surrounding planets, planetoids, asteroids, natural and artificial satellites, gas clouds, neutrinos and dark matter is officialy my sole property according to copyright law #1361. If you dare come into the 235 934 347 238 484 km radius of this solar system, I will sue you to death according to the super duper interstellar DMCA.

    You have been warned, I saw it first!

    1. Re:My property! by mike_mgo · · Score: 2, Insightful

      More importantly, when are people going to learn that these lame copyright jokes aren't funny or clever. Especially in an article that has NOTHING to do with copyright/SCO/RIAA or whtever.

  8. Yes by Alethes · · Score: 2, Funny

    According to the article that you didn't read, which has a title of "Star survey reaches 70 sextillion," you could use the term "70 sextillion."

  9. Just amazing by Blenderkitty · · Score: 2, Insightful

    It's also about 10 times as many stars as grains of sand on all the world's beaches and deserts.

    Everyone you know, everything you've touched, all of human history, on one of 70,000,000,000,000etc stars...

    The universe is so amazing...there's just so much stuff to see out there...I hate being chained to JUST ONE PLANET!

  10. sex..! by atari2600 · · Score: 2, Funny

    sext...damn another metric cousin...call me back when instr(postonSlashdot,3) returns SEX
    *goes back to room*
    SHIT ITS 2003!!

  11. Re:huh... by Jafafa+Hots · · Score: 2, Funny

    They probably figure that "million" is about the biggest number people can imagine... start using other terms and you might as well be saying "eleventy hundred gazillion heptavillion loopadillion." Doesnt mean anything to the average person.

    --
    This space available.
  12. Some other numbers for comparison by notyou2 · · Score: 4, Interesting

    30-60 sextillion: The combined number of cells in every living human being on the planet.

    51 sextillion: The number of grains of sand it would take to cover the entire planet once.

    -- CALCULATED FROM --
    There are 6 billion people on the planet. Web searches yielded varying figures of approximately 50-100 trillion cells per human being. The "average" grain of sand is 100 microns across (and I grossly approximated a sand grain as being square).

  13. Approaching Avogadro's number by notyou2 · · Score: 5, Interesting

    That's almost spooky... Avogadro's number is approximately 600 sextillion.

    What if it turns out that, after taking into account all the dark matter, the universe contains Avogadro's number of "large objects"? (stars, planets, whatever)

    Could the universe turn out to be nothing more than one mole of stars? :)

    1. Re:Approaching Avogadro's number by Gyl · · Score: 3, Informative
      It would be an interesting, and random conincidence. One mole, is the number of carbon 12 atoms needed to make exaclty 12 grams of carbon 12. (Something in there is defined by that relation, I'm not sure if it's the mole exactly.) Seeing as the gram is an entirely arbitrary unit of mass, this number is entirely arbitrary. I know, I know, that's the boring answer.

      If the universe contains an Avogadro's number of stars then the universe has exactly 1 Ug (universe gram) of mass. Where the universe atomic mass unit is one star; 10^33 or 10^34 grams as we know them. :P

  14. Re:Total mass by schmink182 · · Score: 2, Informative

    IANAPhysicist, but I'm pretty sure I can answer some of your questions. It has been theorized that the speed of light has changed in the past, and therefore can continue to change. However, if light used to be slower, then matter could still not travel faster than the slower speed, following all the current known laws. As far as I can tell, if the universe's expansion were to accelerate past the speed of light, then the force of gravity would be unable to slow it back down. Sadly, with regards to the initial question of how we can see light from the beginning of the universe, I unfortunately have no idea.

  15. Re:Total mass by Mattcelt · · Score: 5, Informative
    IANAP, at least not professionally, though I think I may be able to shed some light (or at least a few photons) on your questions.

    I find it interesting that they determined an estimate of the total mass of all the matter in the Universe before they figured out how many stars there are. You'd think they'd come up with the number of stars first, and then base the mass estimate on that.

    You are right in thinking that intuitively, this would be the way to work it. (I know that it would be if I were approaching it, but then these guys are probably smarter than me.) The interesting thing is that as part of the work Einstein did, there was a mathematical shortcut which allows us to calculate the total mass of the objects in the universe based on their collective gravitational effects.

    It works like this:
    1) The universe has a certain amount of objects, each of which have mass.
    2) We know that any object that has mass will have a gravitational effect on all others (in the amount of the inverse of the square of the distance between them).
    3) We can calculate with reasonable certainty (with infinite sequences - similar to the Fibonacci spiral, etc.) what the total effect of all the gravity would be in the universe based on any arbitrary amount of mass that exists in the universe.
    4) We can tell how much of an effect the total gravitational force is by measuring the effects of gravity on galaxies, namely how fast the galaxies are moving, whether they are moving away from or towards one another (on a large scale), and whether the galaxies farther out are moving more slowly or faster than the ones close by.
    5) We know what effect (through the math again) a certain amount of mass (x) would have on the universe as a whole. To be more specific, we know that if the equation with (x) works out to be greater than 1 (i.e., f(x)>1, which was sort of arbitrarily chosen, but bear with me here), the universe will eventually pull itself back together and gravity will cause it to end in a big crunch the opposite of the big bang. If (x) makes the equation *exactly* 1, (i.e., f(x)=1), the universe will reach a point of equilibrium and remain stable for eternity. If the value of (x) makes f(x)Interestingly enough, physicists cannot seem to figure out where more than 10% of the matter they think *should* exists is! Based on the empirical evidence, they know that the value should be something like f(x)=.99999999999999999 or something very close to, but ultimately smaller than, 1. In order to make this equation work, they know they need a certain value for (x). But they can't seem to figure out what more than 10% of (x) is - galaxies, stars, black holes, etc. can only account for a small amount of the overall mass needed to make the universe behave how it does (there is a technical reason for this conclusion, but I don't understand it well enough to explain it here).

    The other 90% is something physicists call "dark matter", because they haven't been able to see it yet. They're not even sure it exists - the formula may need to be refined somewhat. Einstein discovered this anomaly when he first devised this theory and the math behind it. So he added a "fudge factor" to his equation which helped it all come out in the end. He gave it a spiffy name to make it sound legit - it's called the Cosmological Constant. Before he died, he called the creation of the CC his biggest mistake, but physicists have been absolutely unable to shake it yet, because they still don't know why there's such a big discrepancy between the matter they know about and the matter they need to make the equation perfect. It's one of the great mysteries of physics still.

    As for your second question, "if that light has been traveling that whole time toward us, how did we get here first?", think about this: if you are travelling away from someone at the speed of light, and there is one light second between you when you emit a photon, it will take one second for that photon to reach the other perso

  16. Re:if it's a million million million, by nomel · · Score: 2, Interesting

    Remember, the visible universe is growing by a lightyear every year as light is just hitting us from very distant stars. :)

  17. Molecules of sand by philip_bailey · · Score: 2, Insightful

    By my calculations, 7 x 10^22 is the number of molecules in approximately 7 grams of sand. There is certainly "plenty of room at the bottom"...

    --
    There is no place like ~!
  18. Ponder this by DigiShaman · · Score: 2, Interesting

    Throughout an entire human lifetime, the collective count of every neuron transmission in the brain will never reach the total amount of stars in the universe! So even if we had the physical means to travel to all of the stars, our mental capacity would be the limiting factor.

    --
    Life is not for the lazy.
  19. Re:Total mass by Zan+Zu+from+Eridu · · Score: 2, Informative
    You can't compare the Hubble constant (the speed of expansion) to the speed of light.

    The universe expands by growing empty space everywhere, not just at its edges. This is why you measure the Hubble constant as speed per distance, (ie. kilometers per second per Megaparsec). If you want to compare c (speed of light) to H0 (Hubble constant) you'll have to agree on over which distance you're going to compare them. If you make the distance (the Megaparsecs) big enough; H0 will always win.

  20. Re:That's One Amazing factoid! by Zardoz44 · · Score: 3, Informative
    How about this then:
    The Dish
    I couldn't watch the whole thing myself, but I believe there was at least one Australian astronomer in it.

    Better yet, lets get some "real" info about this:

    40 Years of the Dish
    Now you know.
  21. Finally! :) by Anonymous Coward · · Score: 4, Funny

    Now I can break all these romantic star-watching nights:

    She: I wonder how many stars are out there *dreams*
    I: 70 sextillion b1tch, OWN3D *walks away*

  22. Huh. What are the odds... by jpsst34 · · Score: 3, Funny

    ...that it would have turned out to be such an even, round number?

    70,000,000,000,000,000,000,000 Stars Out There

    I mean, I would have thought it to be something more like 70,432,268,111,955,196,651,769 Stars Out There

    --
    How are you going to keep them down on the farm once they've seen Karl Hungus?
  23. Re:Huh. What are the odds... by Tharsis · · Score: 3, Funny

    he, you missed one.

  24. Just means more names... by jbarr · · Score: 2, Funny

    ...for the International Star Registry to sell!

    --
    My mom always said, "Jim, you're 1 in a million." Given the current population, there are 7000 of me. God help us all!
  25. Re:if it's a million million million, by quantaman · · Score: 2, Informative

    Remember, the visible universe is growing by a lightyear every year as light is just hitting us from very distant stars. :)

    Not quite, remember the universe started from a central point with the big bang including those very distant stars. Also nothing can travel faster than the speed of light therefore we theoretically could see the entire universe given a strong enough telescope though much of what we see at the distant edge will be very young (it's still possible that there are stars currently outside the current radius of what we can see if they're expanding at almost the speed of light but we can watch them or their ancestors drift out there and they won't pop up).

    Unless of course the big bang opened massive worm holes and sprouted up universes all over the place, then the light from them could be meeting us eventually and just pop out of nowhere...

    --
    I stole this Sig
  26. 70 Quintillion by mrmeval · · Score: 2, Informative

    That's Quintillion I say.

    Million
    Billion
    Trillion
    Quadrillion
    Qunitil lion
    Septillion
    Sextillion (boys and girls like this one)
    Octillion
    Nonillion

    --
    I'd go on a Vegan diet but the delivery time from Vega is too long. --brownkitty
  27. It is still only half the number of... by FauxReal · · Score: 2, Funny

    porn sites on the internet.