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"Next Week's Eclipse of the Frosty Beaver Moon:
The Last of the Two Total Lunar Eclipses of 2003"
Back on May 15th we were treated to the first of two total lunar eclipses for 2003. Next week, on Saturday, November 8th, the second will occur and Sky Park visitors will be able to see it. In various North American Indian legends November's full Moon is called "the Frost Moon" or "the Beaver Moon." But it would be better to be named "The Rainy Season Moon" in the Sky Park. On Bonaire the eclipse event will begin at sunset. As the moon rises higher and higher in the sky more and more of it will get "eclipsed."
How does an eclipse happen? Let's imagine that we're out in space looking down on our Moon, Earth and Sun. Now as most of you know, our Moon does not make its own light. Moonlight is really light from the Sun reflected off the Moon and back to our Earth. One half of the Moon is lit up by the Sun at all times, although the only time we see the half of the Moon that is completely lit up is when we have a full Moon which occurs every month, whenever the Moon is directly opposite the Sun as seen from Earth.
Usually when we have a full Moon the Moon is either above or below the plane of our Earth's orbit. But occasionally the full Moon will glide directly into our Earth's plane and will pass directly through our Earth's shadow cone, which will block most of the Sun's light from reaching it. In other words our Earth's shadow will block the light of the Sun from reaching the moon. We call such an event an eclipse.
Now, during an eclipse the Moon never completely disappears but always turns some unpredictable shade of reddish copper orange. And that's because the red rays of sunlight are always bent by our Earth's atmosphere into our Earth's shadow, filling it with a faint reddish copper orange light. So, during a total lunar eclipse the reddish orange color you see is actually light from all the sunrises and sunsets around the world being refracted into our Earth's shadow then onto the Moon and then reflected back again. And that's what you'll see early Saturday evening, November 8th.
Now if we could look at our Earth's shadow more closely we would see there are two distinct parts to it: a pale outer shadow called the penumbra and a smaller dark shadow called the umbra. The penumbral phase of the eclipse is never very noticeable so I'm suggesting that you start watching at 6:32 pm, Bonaire Sky Park Time, when the Moon starts to enter the umbra because as minute after minute goes by you'll actually see our Earth's curved shadow slowly creep across the Moon and the Moon will gradually darken and change color. During totality, which begins at 8:06 and ends at 8:31, the Moon will be completely within the Earth's umbra and totally eclipsed for 25 minutes after which the whole process will slowly reverse. What color will the Moon turn during totality? No one knows for sure. That's what makes it fun! Don't miss Saturday night's eclipse of the Moon. Jack Horkheimer
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