Stars and grains of sand...show me!?

Question

This comparison has come up several times. I did some calculation. Others have claimed more stars, even billions of times more stars. Show me. Who said this on TV? What are the calculations. It's just a lot of big number arithmetic, y'know. I have figured that 10^21 grains of sand (or was it 10^22?) would take up a space 100 miles wide, 200 miles long, and ten feet deep, in the Sahara desert. Can someone show me how the number of stars is greater than the number of grains of sand on earth? Or does it just sound cool to say that?

The number of stars in space is not commonly believed by astronomers to be infinite. There would be no comparison at all, if that were the case. I want to know where some of these other comparisons come from. Hopefullt some of the people who stated them will tell me.

Based on my estimate of a million grains per cubic inch, the Sahara desert alone would be more than 10^23, or 100 times my first comparison. And beaches don't end at the shore. I still say, more sand grains. People who have been saying otherwise, please show where I am making my mistake.

Answer 1

SPACE (with matter = stars) IS NOT INFINITE. its shape is pulsing and changing.

its a ridiculous assumption. I think its said just to make one think of the vastness of space. I don't think its possible to account for all the sand on earth anyway. I mean did anyone consider mud or rock. (sand in different forms)
after learning more about space and its shaping we will come CLOSER to a correct answer.

“To see a world in a grain of sand....”
http://discovermagazine.com/2007/jun/how-much-does-the-internet-weigh

wow, check out this nasa site. of the subject but made me think
http://science.nasa.gov/headlines/y2005/16nov_gpb.htm

Answer 2

I've heard Carl Sagan say this in his Cosmos series on PBS. But I doubt he actually did the numbers. What he was trying to get across I believe is that "space is a very big place," as Jodie Fisher said it in "Contact." I think he was trying to impress us on just how many stars there are and how much that increases the possibility of ET life. "It would be a terrible waste of space..." if there were no other life than on Earth.

Check this out:

"SYDNEY, Australia (CNN) -- Ever wanted to wish upon a star? Well, you have 70,000 million million million to choose from." [See source.]

This is from a 2003 news article about the stars in our known universe...the one we can see. No one has a clue about stars beyond our sight horizon.

That's 7 X 10^22 stars in our known universe...about your number of grains of sand for the Sahara desert alone. So we have a few more deserts to account for, like the Gobi, Mexican, Southwest U.S., and maybe one or two more. So, maybe at most, there are 70 X 10^22 grains of sand in all the deserts combined, some of which are really rocky and not at all sandy. But now we need to fold in the beaches; there are a lot of beaches around the world.

According to http://www.hawaii.edu/suremath/jsand.html, the number of grains of sand on all our BEACHES (not including in land deserts) is about 7.5 X 10^18 grains. Several orders of magnitude less than your desert estimate...and mine, with the additional deserts. So, relative to the desert sands, adding in the beaches will not make much of a difference in the number of grains of sand

In any case, comparing the number of stars in our known universe to the number of grains of sand on Earth seems to be a reasonable comparison...about 10^22 for both. But that does not take away from your observation...it is a "cool" thing to say...Sagan was good at that.

Answer 3

The universe is maybe infinite but bounded (not infinite unbounded). Think the surface of a sphere rather than infinite piece of paper.

However our galaxy has roughly 100,000 million (10^11) stars in it this is average for a galaxy. There are roughly 10^10 galaxies in the observable universe making at least 10^21 we can see.

The universe is far bigger than the observable one so we can assume there are more.

Best I can do as it is all about estimates.

Answer 4

what's with all these people saying that the number of stars are infinite?? How much space would 300 billion grains of sand take up? my guess is a whole lot of space, and that's only 1 average galaxy!!

Answer 5

that's completely a probability for there to be greater planets interior the universe than grains of sand in the worldwide. fairly aside from the communicate as to if or no longer the universe is infinite or increasing, we are in a position to basically see a tiny fraction of what's accessible in our very own galaxy - no longer to show the different galaxy.

Answer 6

I am not a math whiz, but I do know that the number of grains of sand is finite. The universe has no beginning and no end, and since we see stars as far as we can see, we can assume that that part of the universe which we cannot see also contains stars. So since the universe is infinite, so must be the number of stars. Sorry, I don't have a mathematical formula to prove it.

This is an interesting argument, but there are so many other things to idly ponder that are so much more important and useful.

Answer 7

Since the universe is infinite, ergo the number of stars within that universe are also infinite and the grains of sand on the Earth are finite, the has to be more stars than grains of sand.

Answer 8

grains of sand is one where as the stars are in a infinite space so there is no one that can say how many stars there is