Does the moon have any advantages or disadvantages for the earth?

The moon and the earth constitute the most basic unit of the celestial system - the Earth-Moon system (celestial body level: Earth-Moon system - solar system - Milky Way - total galaxy), and they can be said to be inseparable from the earth. , the relationship is extraordinary. Its impact on the earth is relatively obvious, mainly in the following two aspects: ① Everyone knows that the natural lighting at night on the earth mainly relies on the moon. Otherwise, the nights on Earth would be pitch black and unimaginable. ② The attractions of the moon and the sun are different everywhere on the earth's surface, so the water bodies on the earth produce corresponding obvious tidal phenomena (in ancient my country, people called the rise and fall of sea water in the morning tide, and the rise and fall of sea water in the evening The rising and falling conditions are called tides, and the two together are called the tidal phenomenon. The tidal phenomenon of the sea surface rising and falling periodically is mainly caused by the different gravitational forces of the moon and the sun on the earth.)

Tides

Just like the Earth's gravitational pull on the Moon, the Moon also has a gravitational pull on the Earth, which makes the Earth slightly elliptical. This deformation has little impact on solid land. , but causing tides along the coastline. Tides, in turn, affect how quickly the Earth spins and its distance from the Moon.

When the earth's surface enters and exits the ocean expansion zone caused by the moon's gravity, the ocean surface experiences two high and low tides every day. The actual height of the tides depends on the moon's position in its orbit, as well as the local topography.

The cause of tides

On the Earth, the seawater closest to the moon feels the moon's gravity the most; conversely, the seawater on the far side of the earth experiences the least gravity from the moon. As the Moon orbits the Earth, two tidal highs form and travel with the Moon across the Earth's surface. The Earth's rotation causes the tides to be slightly ahead of the Earth's, rather than in a straight line with it.

Spring tides and neap tides

At the full moon and new moon, the sun, earth and moon are exactly in a straight line. The gravitational pull of the sun and the tidal force of the moon combine to produce the highest high tides and the lowest low tides, known as spring tides. During the first and last quarter phases of the moon, a right angle is formed between the sun and the moon. The Sun's gravity partially offsets the Moon's tidal force, causing neap tides.

The tidal force of the moon

NASA scientist Dr. Sheru Pearson pointed out that when the solar system was first formed, the moon was pulled by the earth and became its satellite. As the moon was pulled closer to the earth, it had a great impact on the earth.

The moon exerts a tidal force on the earth. Scientists have confirmed that the lunar gravitational tide has the following effects:

(1) The lunar tidal force can stabilize the tilt angle of the earth's rotation axis, thus making the earth's climate relatively stable. As we all know, the moon and the earth are two different celestial bodies that have a gravitational effect on each other. Now the tilt angle of the earth's rotation axis changes within 5 degrees. However, without the moon, the tilt angle of the earth's rotation axis would change from 0 to 50 degrees in a cycle of millions of years. The earth's climate would also undergo drastic changes as a result, and the earth would eventually become an environment in which living things cannot survive. .

(2) The tidal force of the moon will also stir up the atmosphere, forming the so-called "air tide". "Air tide" can affect air pressure and weather. For example, air pressure is often lower during a full moon. Relevant research also found that the most severe storms in the United States occur 1 to 3 days after the new moon or 3 to 5 days after the full moon. Therefore, some argue that the phases of the moon should be taken into account when forecasting weather.

(3) The earth will warm slightly on a full moon night. This was discovered by Robert Baring and Randall Sevigny, climatology experts at Arizona State University in the United States, by analyzing weather satellite observations. Over the past 15 years, weather satellites have accurately measured the subtle changes in Earth's surface temperature caused by moonlight and found that the Earth's average temperature increased by 0.017 degrees Celsius during the full moon.

The moon disturbs the human body

Man and the moon are also very closely related. Psychiatrists point out that about 80% of the human body is liquid, and the moon’s gravity can also affect the human body like ocean tides. The liquid in the body acts to cause "biological highs" and "biological lows" in the human body. At the time of the full moon, the biological tide is at its peak, and the moon has a strong influence on human behavior. At this time, the potential difference between the human head and chest is relatively large, and people are easily excited, emotionally unstable, and prone to accidents. According to statistics from the Japanese Fire Fighting Association, every night when the moon is full, there are 25% to 30% more fire alarms than usual; Weber wrote in the book "The Influence of the Moon": "In September 1970, when the tide was high, the number of fire alarms in Miami, USA The number of homicides and hospitalizations in mental hospitals has increased than usual. "For example, young people like to fall in love on moonlit nights, while alcoholics and mentally unstable people often have attacks on moonlit nights. Maures, a professor at Illinois State University in the United States, even pointed out that human murder, poisoning, depression and heart disease are also related to the waxing and waning of the moon.

A doctor in the United States investigated more than 1,000 patients on the operating table and found that the patient's bleeding was related to the movement of the moon. Survey data shows that 82% of the patients have a bleeding crisis between the first quarter of the moon and the last quarter of the moon, and patients who bleed when the moon is full are most at risk. Therefore, many doctors are most afraid of operating on patients on a full moon night.

The American Medical Association collected 500,000 birth charts of babies over 20 years and found that most babies were born during the waning moon (the last quarter of the moon); most mothers along the coast of the Netherlands gave birth when the tide was high. The secret is that the moon affects the contractions of the uterus.

Moon-induced earthquakes

When the gravitational pull of the sun and the moon on the earth

is the largest, earthquakes are often prone to occur. Earthquakes can generally be divided into tectonic earthquakes according to their causes. and volcanic earthquakes. For most tectonic earthquakes, the occurrence of the earthquake mainly depends on whether the crustal rock layers there are on the verge of fracture. On the lunar calendar (the first day of the lunar month) and Wang (the 15th and 16th day of the lunar calendar), the three celestial bodies, the sun, the moon, and the earth, are close to a straight line. At this time, the tidal forces of the sun and the moon are combined, and the tidal force on the earth is greater than usual. Much bigger. This gravitational force not only causes tidal phenomena in seawater, but also causes changes in the earth's crust similar to rising and falling tides, forming a "solid tide" that can trigger the crust that is about to break and induce earthquakes. American seismologists believe that when the gravitational pull of the sun and moon on the earth is greatest, earthquakes are often more likely to occur. According to statistics, there have been 13 major earthquakes of magnitude 7 or above since the 20th century. It was found that there were 2 earthquakes that occurred at the time of Shuo and Wang; 2 earthquakes occurred 1 day apart from Shuo and Wang; 5 earthquakes occurred 1 to 2 days apart from Shuo and Wang, totaling 9 times, accounting for the total number of statistics 69.2% 13 times. This is enough to show that the gravitational force is strong during the first and last 2 to 4 days of Shuo and Wang, and earthquakes are prone to occur. The statistics are shown in the table below: Statistical table of induced earthquakes during the New Moon and Moon Periods

Name Magnitude Time of earthquake onset Distance from the Moon and Moon 1 Days from the San Francisco Earthquake in the United States 8.3 January 18, 1906

Wang 9 days 2 Japan’s Great Kanto Earthquake 8.2 September 1, 1923 5 days away 3 Tangshan Earthquake in China

7.8 July 28, 1976 1 day away 4 Bucharest Earthquake in Romania 7.5 March 4, 1977

Sunday 5 Tabas earthquake in Iran 7.7 September 16, 1978 1 day 6 Erzurum, Turkey 7.

1October 13, 1983 7 days 7 and Kars Province Earthquake

Mexico City Earthquake 8.1 September 19, 1985, 4 days from New Year’s Eve, 8 Armenia’s Lenin Naskan Earthquake

7.1 December 7, 1988, 3 days from New Year’s Eve, 9 The San Francisco Earthquake in the United States was 7.1 on October 17, 1989, 2 days and 10 away. The earthquake in northern Japan was 7.8 on July 12, 1993, and the Taiwan Strait Earthquake in China was 7 and 11 days away. 7

.31994 Earthquake in Lijiang, Yunnan, China, 7.0 on September 16, 1996, 4 days away, 13 on February 3, 1996

Earthquake in eastern Iran, 7.1, 3 days away on May 10, 1997 Knowledge points

The First Quarter Moon and the Last Quarter Moon

The First Quarter Moon and the Last Quarter Moon look similar, but the time, location and direction of their bright side are different. In the western sky before the first quarter moon appears, their "face" faces west, that is, the western half is bright; while the waning moon appears in the eastern sky in the second half of the night, and their "face" faces east, that is, the eastern half is bright. Since the lunar calendar dates in our country are arranged according to the moon phases, the working people in ancient my country sometimes relied on it to judge the lunar calendar dates and the approximate time of night.