Physics Photo of the Week - April 30, 2004

Warren Wilson College

Color photographs of different aged star clusters

M67 in Cancer is a very old open star cluster.  It is believed to be between 4 and 8 billion years - about the age of the solar system.  Notice the preponderance of "yellowish" stars and only a few blue stars.  These red/yellow stars have evolved into red giants.
h Persei.  In contrast to M67 above,  h Persei is very young - estimated to be only about 6 million years (1/1000 the age of M67).  As a result the bright stars are predominantly blue and extremely hot as compared to the red stars of the much older M67.

When this cluster was born, the dinosaurs on earth were long gone, mammals had appeared, and the first human-like creatures were starting to appear.

These photos were taken Donald F. Collins using a Meade 8-inch Schmidt-Cassegrain telescope and an inexpensive digital camera.  The photos have been enhanced to emphasize the colors.

Further information may be found at the SEDS (Students for the Exploration and Development of Space) web site.

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