The last chance to watch a lunar eclipse in North America this century happens Thursday.

The eclipse will begin around 8:30 p.m. and be completed about 11:30 p.m. Dr. Michael Cobb, chairman of the physics department at Southeast Missouri State University, said the eclipse is visible without binoculars or telescopes, but either would enhance the view.

A lunar eclipse happens when the Earth casts a shadow on the moon. The eclipses happens once or twice a year. "For us in North America, this is the last convenient one until the year 2000," he said.

About half of lunar eclipses happen during daylight hours and can't be seen.

Watching a lunar eclipse isn't very dynamic. It happens slowly over the course of a couple of hours. Cobb recommends going outside about every 15 minutes to watch the progression of the eclipse.

"Slowly you will see a region of the moon growing dim," he said.

The moon remains visible during the eclipse, but its color changes. The color during the eclipse is related to the atmospheric conditions at the time. Cobb said the moon should appear copper or orange-ish in color because the atmosphere is relatively clear. After volcanic eruptions, for example, an eclipse would be very dark.

A solar eclipse is basically the opposite of a lunar eclipse. The shadow of the moon falls on the Earth. Solar eclipses happen much more quickly and are more dramatic to view.

Members of a new astrology club will be viewing the eclipse Thursday, Cobb said. The group meets Mondays at 6 p.m. in Rhodes Hall and is open to the public.

Cobb said Saturn is located within 2 degrees of the moon and will be the bright star seen.