Astr111 Photography Projects, Fall 2004

M 13, Karen Ring

The image that I captured was the globular cluster M13, otherwise known as the Hercules Globular Cluster. This cluster was first discovered in 1714, by Edmond Halley, who also noted that it is visible to the naked eye when the night sky is dark enough. M13 is 25,100 light years away, and contains maybe as many as one million stars. It is much more concentrated in its middle, and also contains one (relatively) young blue star, Barnard No. 29. Although age is a relative term when discussing stars and the universe, estimates are that this globular cluster is anywhere from 14 to 24 billion years old.

The photo that was taken for me clearly shows that the stars are more concentrated and intense in the middle. This image also shows a sort of spray outward, or grouping inward. This can be attributed to either a big bang in the centre of the cluster forcing the other stars outward, or gravitational force drawing the stars toward the centre. I have tried to make the image as clear and white as I could, although it is much clearer on other pictures from the Observatory Website.