DETROIT – You've been hearing all about it, and many of you have questions. I'm talking about this week's "super blue blood moon." First, let me explain what's going to happen and why, and then I'll get into what we will and will not see here in southeast Michigan.
Lunar eclipses, by themselves, are not terribly uncommon. They happen from time to time. And, unlike a solar eclipse, you can look directly at a lunar eclipse without any special eye protection.
Early Wednesday morning, the moon, Earth and the Sun will all line up perfectly, with the Earth in between the sun and the moon. When this happens, there's an opportunity for the moon, as it orbits the Earth to pass through Earth's shadow.
When this happens, a dark smudge starts creeping across the moon's surface as it passes through the outer part of the shadow, which is called the penumbra. When the moon's surface passes into the heart of the Earth's shadow, which is called the umbra, it turns a reddish color due to the sun's rays being refracted, or bent -- just like by a prism -- when they pass through Earth's atmosphere.
The reddish color is why an eclipsed moon is frequently called a blood moon.
So what makes this one so special? Well, Wednesday's full moon is our second full moon of the month, which is commonly called a blue moon.
Furthermore, as I've explained in the past, the moon's orbit around Earth is not a perfect circle, it's an ellipse. So there are times of the year that the moon is closer to us, and times of the year that it's farther away.
The change in distance really isn't that noticeable, but full moons that occur near when the moon is closest to the Earth, or at the perigee, are called super moons.
So, since we have a lunar eclipse occurring during the second full moon of the month when the moon is near its closest position to the Earth, we have a "super blue blood moon." According to EarthSky.org, the last blue blood moon to occur in the U.S. was in 1982. Obviously, throw in the "super" element, and you can see that this doesn't happen very often.
So what will we see here in Metro Detroit? Not as much as we'd like. The eclipse will begin at 6:48 a.m. Wednesday, but the moon here will be setting at 7:48 a.m., so it's going to be low in the western sky.
Trees and buildings are going to block the view for many. If you are in an area with a clear view of the western sky, you'll see a smudge moving across the moon between 6:48 a.m. and 7:48 a.m.
But the moon will be setting just before it's totally eclipsed, so we won't get to see that happen. As you head west of the Great Lakes, the moon will be higher in the sky. So the farther west in the country you are, the more of the eclipse you'll see.
Our biggest problem may end up not being either the timing or the moon's position in the sky. It may be the weather. Right now, it appears that clouds will be increasing Tuesday night, so all of our efforts to see even a part of the "super blue blood moon" may end up being worthless.
The Local4Casters are watching this carefully, and will update you on Local 4 and on ClickOnDetroit.com.
Even though we probably won't be able to see it, the "super blue blood moon" is still very cool to think about, because this is science that's easy to understand.
If you have friends or relatives out west who see it and get any good pictures, have them download our Local 4 Storms Pins app and post them. The app is free and can be found in the app store under "WDIV." We'll try to get some pictures on the air.