Moon Question of the Day


Where did the names of the days of the week come from?

The Babylonians named the days after the five planetary bodies known to them (Tuesday through Saturday) and after the Sun and Moon (Sunday and Monday). This custom was later adopted by the Romans. Emperor Constantine established the seven-day week in the Roman calendar in 321 and designated Sunday and Monday as the first two days of the week. The other weekday names in English are derived from Anglo-Saxon names for gods in Teutonic mythology. Tuesday comes from Tiu, or Tiw, the Anglo-Saxon name for Tyr, the Norse god of war. Tyr was one of the sons of Odin, or Woden, the supreme deity after whom Wednesday is named. Similarly, Thursday originates from Thor, the god of thunder. Friday is derived from Frigga, the wife of Odin, representing love and beauty. Saturday comes from Saturn, the ancient Roman god of fun and feasting.

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Last 7 Days

What is the temperature on the Moon?

Daytime temperature is about 235 degrees F. Nighttime temperatures can drop to -275 degrees F.

Is there a rhyme about the color of the Moon and how this color can foretell the weather?

There are several, but the one most familiar to us is "Pale Moon doth rain, red Moon doth blow, white Moon doth neither rain nor snow".

What and when is the feminine side of the Moon?

The Moon has neither a feminine nor a masculine side. Your idea probably comes from the popular interpretation of the Moon's surface features, as seen with the naked eye, as the "Man in the Moon." In modern scientific English, the Sun and the Moon are each spoken of as "it"; only in poetic language is the Sun "he" and the Moon "she." As far as we know, in all other western languages, including scientific use, the Sun is masculine and the Moon is feminine. The interesting exception is German, in which the word Moon uses a masculine article and Sun uses a feminine article.

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?

How come longitude lines start in Greenwich, England?

The Royal Observatory Greenwich is located at the National Maritime Museum in London. The original site of the observatory was arbitrarily chosen as longitude 0 degrees in 1884. A plaque in the original structure marks the zero point from which longitude is calculated. The observatory was founded in 1675 by King Charles II to keep accurate tables of the position of the Moon for the calculation of longitude by English ships. In 1750 those tables were published as the Astronomical Observations, and after 1838 they were published annually. Meridian observations of the Sun, stars, and planets also were made at the observatory. Photographs of the Sun were taken daily, conditions permitting, and a continuous photographic record of sunspots was kept starting in 1873. Today the observatory is primarily a museum with a small planetarium.

Does the Moon rise and set in any particular time pattern?

The rising and setting of the Moon is retarded from day to day, but the delay is not consistent. At moonrise, the Moon occupies a particular place in the celestial sphere. Approximately 24 hours later, the Moon has moved to the east in the sphere, so moonrise and moonset occur a little later. In the northern United States, the daily delay can vary from a few minutes to well over an hour.

Why don't eclipses occur every month?

If the Moon always moved on exactly the same path, and if that path crossed in front of the Sun, there would indeed be an eclipse every month--two of them, in fact, one of the Sun and one of the Moon. But the Moon's path is more complicated than that, and most months it passes above or below the Sun.

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