Is it true a total lunar eclipse occurs when the moon passes through earths penumbra?
Hi Chrissy! What you wrote is untrue. In the earth’s penumbra, there is only a penumbral lunar eclipse. What some of the other answerers wrote is only partly correct, however. To see a total eclipse of the moon, not only must the moon pass through the earth’s umbra, but the moon must go COMPETELY into the umbra. When all of the moon has gone inside the umbra, all of it is completely shielded from direct sunlight. That’s a total lunar eclipse. Sometimes, part of the moon enters the umbra, but the rest of the lunar disc narrowly misses. That’s a partial eclipse of the moon. From earth, we see a bite out of the moon, with part in light and part in darkness. What happens if the moon goes only into the penumbra? Imagine yourself on the moon’s surface, watching the eclipse. When you enter the earth’s penumbra, from the moon you’d see a partial eclipse of the sun. Some sunlight gets through to you, but the earth has gotten into the way of part of the sun’s light. You’re familiar with a partia
