Charles Packard

Ted Coskey

Astronomy 100

May 17, 2009




††††††††††† Last quarter I took Biology 160 and the instructor told the class that we have more cells in an average human than there are stars in the sky.After doing this assignment for counting the clusters of galaxies and knowing that each galaxy can contain from a million to a billion stars, I think she was wrong about how many cells we have, as itís about 4.3 trillion cells and there is much more stars out there I figure in our whole universe.Or maybe the biology instructor was thinking of how many stars you can see with an unaided eye?Regardless of the fact, there are many stars out there and in this assignment only is one galaxy cluster, and there are many more in our universe.

††††††††††† For this assignment I measured 16 cm x 14.4 cm for this 1/10 of the total cluster.I was able to make three square cm and created an edge for the homework sheet which is only 1/10 of the galaxy cluster.I counted 58 for the first one, 34 kind of in the middle of the picture, and 47 to the right of the first one.I added the counted galaxies and came up with an average of 46 1/3 galaxies.Then I multiplied that number by 16 cm and then 14.4 cm and came up with 10,675.2 galaxies shown on the sheet which seems to be a little bit more than I expected but mathematically, itís correct.Therefore, since this is 1/10 of the galaxy cluster, you have to multiply that number by 10, and the final answer is 106,752 galaxies for the cluster.

††††††††††† Then if you multiply 1 billion stars per galaxy you would get around 107 trillion stars and if each galaxy just had a million stars, you would get 107 billion stars, so I averaged those numbers of stars and estimate that there are 53 trillion stars in this cluster which is much more than we have cells in our bodies.However, almost all of your cells split (minus the brain cells and heart) to replace old dieing cells in mitosis, so thatís done an average of every 24 to 72 hours for all the cells in your body, like the liver and stomach.But not every cell, so maybe if you live to be 100 years of age, your cells replicate more than there are stars in the universe?