If you like a good performance, don't forget to look at the moon on the night of Thursday, January 20.

If the sky is clear, you will be rewarded with one of the most arresting sights in the heavens: a total eclipse of the moon.

Lunar eclipses are among the easiest celestial events to observe. You don't have to be an astronomer to see it; just go out at the appropriate time (see below) and find the moon.

You don't need a telescope. And unlike a solar eclipse, there's no risk of damaging your eyes.

Lunar eclipses occur when the moon passes through the Earth's shadow. They can take place only when the moon is full -- and thus directly opposite the sun as seen from Earth.

The most recent lunar eclipse (a partial eclipse) could be seen from the Americas, Asia, India and Australia. North America has not witnessed a total lunar eclipse since September, 1996.

The lunar eclipse on January 20 will be visible to all of North and South America, depending, of course, on the weather.

And this time, there's a bonus: the Earth's atmosphere is cleaner than it's been in about a decade.

In 1991, a titanic blast from Mt. Pinatubo in the Philippines -- the world's largest volcanic eruption in more than 50 years -- sent countless tiny particles of ash high into the atmosphere.

The particles made the Earth's shadow especially dark; during a total eclipse in 1993, the moon seemed to disappear entirely. Now, almost nine years later, the atmosphere is clear again. That means we should be in for a colorful show.

What you'll see hopefully

Here's what you'll see:

In North America, the eclipse will begin at 9:03 p.m. Eastern Time as the moon enters the outer portion of the Earth's shadow, called the penumbra.

It will take about half an hour before you notice a dusky shading building up on the moon's western edge (the left side as seen from North America) and spreading slowly across the lunar disc.

About an hour after the moon begins to enter the penumbra, it will encounter the darker core of the shadow, the umbra.

As the moon enters the umbra (beginning at 10:01 p.m. ET), it will look as though someone took a bite out of it.

The "bite" will grow as the moon moves deeper into the shadow, exposing less and less of the fully illuminated portion.

The part of the moon inside the umbra will take on a coppery reddish hue. The color comes from sunlight being bent by the Earth's atmosphere into the shadow, and falling on the eclipsed moon.

Somehow, these delicate shadings make the moon look remarkably three-dimensional -- like a world in space instead of just a light in the sky.

Two hours into the eclipse, the moon will be fully immersed in the umbra (starting at 11:05 p.m. ET), and the portion of the eclipse known as totality will begin. For this eclipse, totality will last an hour and seventeen minutes, ending at 1:25 a.m. ET Friday morning.

Then, for the next two hours, the "skyshow" will play in reverse as the moon emerges from the Earth's shadow, seemingly reborn in the night sky. The eclipse will end at 2:24 a.m. ET.

To give yourself a personal record of the eclipse, grab some colored pencils and paper and make a sketch. Or, you might try photographing it.

For that, you'll need a tripod for your camera, and film with an ISO number of 200 or higher. Exposure times will vary depending on how much of the moon is inside the Earth's shadow.

For example, using 200-speed film, you might use an exposure of one-two-hundred-fiftieth of a second at f/16 for the full, un-eclipsed moon; one-sixtieth of a second at f/8 for the eclipse's partial phases; and two seconds at f/2.8 during totality.