• On April 25-26, 2013, as seen from parts of Earth (but not North or South America), Earth's dark umbral shadow barely clips the full moon for 27 minutes, causing the third-shortest partial lunar eclipse in the 21st century. There are two more lunar eclipses later this year, but both are penumbral. The April 25-26, 2013 eclipse will be the last time Earth's

dark umbral shadow touches the moon's face until the total lunar eclipse of April 15, 2014.
• What causes a partial eclipse? A lunar eclipse can only happen at full moon, when the moon lies generally opposite the sun in Earth's sky. When Earth resides directly in between the moon and sun, then the Earth's dark shadow totally falls upon the moon's surface. On April 25-26, the alignment of sun-Earth-moon is a little off, so it's only a partial eclipse.
• A lunar eclipse happens when the long shadow of Earth touches the moons face. Earth's shadow has two parts: a dark inner umbra and lighter surrounding penumbra. The moon does go into the darkest part of Earth's shadow tonight, the umbral shadow, but only briefly. Thus tonight's eclipse is an extremely shallow partial lunar eclipse, with only the northernmost portion of the moon passing through the Earth's dark shadow for about 27 minutes. At the greatest eclipse, the Earth's dark shadow will cover less than 1.5% of the moon's diameter.
• If you were on the part of the moon covered over by the Earth's dark shadow, you'd see a total eclipse of the sun. Elsewhere on the side of the moon that faces Earth, you'd see a partial solar eclipse.
• We in the Americas will miss out on the April 25-26 lunar eclipse. Even so, everyone worldwide will get to see a full-looking moon shining near the golden planet Saturn - now nearly at its best for this year - from dusk until dawn. Great night for moon gazing, no matter where you are!
• Who will see tonight's eclipse? The worldwide map on the next page where the lunar eclipse is visible from Earth. Where the gray swaths (South America, New

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