In The New Moon's Arms

If the sky is clear, a rare and startling celestial show will greet early risers Tuesday when Venus, the bright star Regulus, and a crescent moon highlighted by light reflected from Earth will form a tight triangle close to the eastern horizon.

"It is so dramatic that it's almost startling, an exquisitely beautiful event," Jack Horkheimer of the Miami Space Transit Planetarium said Monday. "It's part of the poetry of heavens."

To see the show at its best, look to the east about 45 minutes before dawn from anywhere in the world.

Venus will be at its maximum brightness for the year, and Regulus, a blue-white star that is among the brightest in the sky, also is expected to glow. And for those lucky enough to have really clear conditions, "earthshine" will be visible on the crescent moon.

The effect is created by sunlight reflected from Earth hitting the otherwise darkened moon, illuminating it with a dim glow.

The moon will appear as a thin, bright crescent that seems to cradle the ghostly outline of the rest of the moon. The folkloric way of describing it, Horkheimer said, is "the old moon in the new moon's arms."