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Moon Myths Revealed!
The Solar System > There are several common misunderstandings about our little satellite above, also know as The Moon. I hear them all the time. Let's look at some, and try and clean up its image a bit.
1. One myth is that the Moon doesn't spin around like earth does. All we see is one side of the moon, ever. If the Moon really does spin about, so the thinking goes, we should see the other side of it, right?
Well, it's precisely that it does spin around that allows us to see just one side. Imagine being up a couple stories looking down on two children, one walking a big circle around the other.
In order for the circling child to continue to face the stationary child, that little one must continually turn while walking. If she didn't "spin" slowly while orbiting around, she would appear to be staring at some distant object the entire time. The child in the center would only then see all around the orbiting child's head.
Like the child, the Moon spins around one time for every orbit.
2. The Moon is bigger when it is full and near the horizon.
Sorry, this is a myth, as well. A rising Full Moon is the same size as it is hours later when it is high in the sky. Some believe that this optical illusion flies so well because at the horizon we compare the Moon with points of reference - distance buildings or trees or lights - which make the Moon appear bigger.
We even expect this illusion in artwork. If the Moon is drawn to real scale in the sky of a painting, rather than as a big bright ball, we are not amused; it just looks like it's too small.
Next time there is a full moon, go out when it is on the horizon, when it appears so big, and you'll see that you can cover it with a finger held at arm's length. Wait for a couple hours when it is higher in the sky and try it again. You can cover it then exactly as you covered it when it appeared so big earlier.
3. There is what we can see of the Moon, and then there is the "dark side of the moon."
Not really. There is always a dark side of the Moon, but sometimes it faces us. This is New Moon, when the Moon is between the sun and us. And when we see the so-called "half moon," more accurately called quarter moon, we see some of the lit side and some of the dark side. More accurately that part of the moon we cannot see should be called the "far side" of the moon, not the "dark side."
4. The sun is up during the daytime, the moon is up during the night.
Of course we can define daytime as when the sun is above horizon. But we do not define the night as when the Moon is up. "Nighttime" is when the sun is below horizon. The Moon is part of the definition of neither daytime nor nighttime.
As a matter of fact, during many "daytimes" you can see the Moon - if you know where to look. During this coming week you can see the Moon in the early morning in the western skies. You can then follow it day after day as it moves over towards the sun.
5. We never went to the Moon.
There are some people, few but vocal, who believe all the Apollo missions to the Moon in the late 60's and 70's were a giant hoax perpetrated by our government. I wouldn't even mention this except for the fact that there are a good number of good people out there who are actually sitting on the fence with this one.
The best way I can address this in such a small space is to point you to a website called "Bad Astronomy." Specifically one of the pages there rebuts the Fox TV show "Conspiracy Theory: Did We Land on the Moon?" It is here: http://www.badastronomy.com/bad/tv/foxapollo.html. Go and read and be enlightened.
Actually the next myth is easier to believe than the last…
6. The Moon is made of green cheese.
This one may actually be true. No, I jest! As far as I can tell, using the Oxford English Dictionary as a source, this phrase goes way back, hundreds of years. It was probably used with at least a pinch of sarcasm. Judge for yourself:
John Cotgrave in 1611 gives us, "(Wee say of such an Idiot) hee thinkes the Moone is made of greene cheese." Sir Charles Wilkins in 1638 wrote, "You may as soon perswade some Country Peasants, that the Moon is made of Green-Cheese (as we say) as that 'tis bigger than his Cart-Wheel." (Green in both cases means "new" or "fresh.")
It's like someone today saying, "Soon you'll have him believing the Apollo missions were faked!"
Until next time, clear skies!
Posted by Mark Ritter at 2006.05.14 04:01 PM | Comments (0)
