Take some time this week to observe the Pleiades, one of the brightest and easily recognized star clusters for naked-eye observing. The Pleiades are a cluster of young stars that lie about 400 light-years from Earth. The hot, blue-white stars that make up the Pleiades are surrounded by wisps of gas that shine by reflected light from the stars. Because these stars formed from a great nebula only 100 million years ago, the gas and dust from that nebula still clings to them.

Although they are called the "Seven Sisters," only six stars can be seen without optical aide. Current astronomical studies reveal that between 300 and 500 stars populate this cluster. The six stars that make up the Pleiades are often mistaken for the Little Dipper; however, their outline is more like a tight little "teacup."

To locate the Pleiades, follow Orion's belt to Aldebaran, in Taurus. Continue that line another 15 degrees and it will lead you to this stunning cluster of stars.

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