Moon Question of the Day

Is the distance between Earth and the Moon increasing?

Yes. Because Earth spins slower every day (that's just what spinning objects do), the Moon moves not quite two inches away from it each year. The rate decreases by 1-1/2 thousandths of a second every 100 years -- not enough so that you'd notice, but enough for the Moon's gravitational pull to lessen. This allows its orbit to increase, which results in a greater distance from Earth. Got that?

Last 7 Days

What is a "Catfish Moon"?

We couldn't find specific information on a Catfish Moon. However, in colonial America, the full Moon of March was called the Fish Moon. This probably had something to do with the beginning of fish spawning season along the eastern coast of the United States. Old catfishermen believed the best time to fish was three days before a full Moon to three days after a full Moon. They also believed that the day of the new Moon (the dark of the Moon) was a good time to fish for catfish. Not that you asked, but we did discover a play entitled "Catfish Moon," written by Laddy Sartin, and an Australian blues band of the same name.

What do the phrases "Moon rides high" and "Moon runs low" in the Almanac mean?

As the equator wraps around Earth, so the celestial equator wraps around the sky. It runs in an arc from east to west, passing low in the south; the farther north one stands, the lower it passes. When the Moon runs low in the sky, it is the farthest beneath this equator. If you live sufficiently far north, it will never rise above the horizon at night. Similarly, the Moon will be unusually high in the sky when it rides high.

What is the most recent year that had a full Moon on February 29?

This occurred most recently in 1972. This is indeed a rare event, since the next most recent year was 1820.

Has anyone else seen a Moon rainbow? If so, are they common?

The lunary rainbow, seldom seen, is usually observable soon after dark, following a brief summer storm or shower, when the Moon is nearly full.

What actually causes people to act like lunatics during a full Moon?

From the time of the ancient Greeks and Romans (and maybe earlier), mankind has believed that "the full Moon has the power to tear reason out of a man's head by depriving him of humors and cerebral virtues" (Paracelsus). Scientific studies over the years have tried to link the full Moon with times of increased violence, suicide, mental disorders, and fits and seizures, but results are inconclusive. Some small-scale studies have shown correlations between the full Moon and increased police activity, hot-line phone calls, and hospital emergencies.

Why does the Moon look so much bigger on the horizon than it does once it has risen higher in the sky?

When the Moon is on the horizon, you have other objects, such as houses and trees, to compare it to, so it looks larger. Once the Moon is in the sky, the only things to compare it to are the stars, which appear as tiny points of light. Hence the Moon looks smaller once it has risen.

What exactly is a waning or waxing gibbous or crescent Moon?

First, gibbous refers to the shape you can see when the lighted surface of the Moon is bigger than a crescent shape; the crescent shape is defined by the distinct points on the lighted sliver. The Moon moves in these phases: new Moon, waxing crescent, first quarter Moon, waxing gibbous, full Moon, waning gibbous, last quarter Moon, waning crescent, back to new Moon. So waxing means the moon is on its way to being full; waning means the Moon is on its way to being new (the phase you really can't see).

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