Jack Scott in Baltimore says he was taught that the dark portion of a less-than-full moon is caused by "the sun casting the shadow of the Earth upon it." But after seeing the sun rise alongside a crescent moon, he asked, "How can that be?" Re-read your class notes, Jack. The dark portion lies in the moon's own shadow. It's the side facing away from the sun. Earth's shadow falls on the moon only during lunar eclipses.
Advertisement
