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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."
are J-Lo and Ben Affleck...bummer
[quote]Asked if he believed the huge scale of the universe meant there was intelligent life out there somewhere, he told the paper.
... it's inevitable."[/quote]
"Seventy thousand million million million is a big number
Good thing i'm keeping my seti@home client running all the time... we're bound to find something sometime!
In linux libertas
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, 2, 3, 4, 5...
Beware blue cats moving at
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).
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!
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.
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).
DiscDividers tabbed plastic CD dividers: divider cards f
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?
DiscDividers tabbed plastic CD dividers: divider cards f
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
Better yet, lets get some "real" info about this:
Now you know.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*
...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?
he, you missed one.