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Name: m french
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1993 - 1999


Question:
Are there more stars or are there more grains of sand?


Replies:
Well, if every star came with a planet like earth that had billions of sand grains, there would have to be more sand grains than stars! The number of stars in our galaxy is around 100 billion or 10^11 in exponential notation. The number of sand grains on earth is probably somewhere between 10^20 and 10^24. Th e number of sand grains on earth is therefore much greater than the number of stars in our galaxy. However, our galaxy is only one of about 100 billion in the visible universe, and so the total number of stars we know about is around 10^22, which is kind of in the same ballpark as the number of grains of sand on earth.

Of course, those numbers are much bigger than we can count - I'm not sure whether better estimates of both numbers would give more stars, or more sand grains - there's a lot of both!

A Smith



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