by Todd Elder at Exploring Creation
The Moon is Earth's only natural sattelite. It produces no light of it's own, but reflects the light from the sun. Interestingly, it would not be able to maintian a round spherical shape if it were much smaller. It is about 1/4 of the earth's diameter measuring 2,160 miles across. It averages 238,850 miles from the earth. The temperature ranges from 253 degrees farenheit in the day to -378 degrees farenheit at night.
The moon orbits the earth every 27.3 days, however because of the motion through space and the rotation of each an entire cycle from one new moon to another measures 29 days, 12 hours, 44 minutes 2.841 seconds. The non-concentric orbit also means that from new moon to full moon takes 13.73 days while full moon to new moon takes 15.80 days. In astronomical terms, the new moon is the dark of the moon at conjunction (when it is located between the earth and the sun). The full moon is when it is located opposite the sun from the earth.
The earth, moon, and sun have a unique size and distance relationship that is unknown anywhere else in the universe. The moon is 400 times smaller than the sun and 400 times closer. This gives both an appearant size of 1/2 of an angular degree in the sky. It is this condition which allows for the moon to eclipse the sun so precisely. Historically, this also allows us to know that the calenders made and used by the Old Testament writers was accurate.
No life has ever been found on the moon. When the first two Apollo missions returned to the Earth, they were quarantined.
Some calendars are based on using the moon to determine the months. Among the more accurate of these are those based on the Metonic cycle (named after the Athenian astronomoer Meton). This cycle follows a 19 year pattern because 19 solar years exceed 19 lunar years by about 209 days which is about 7 months.
Gravity is the key force involved in making the tides of the Earth. Technically, the water is pulled on by the sun's gravity more than the moon's, but since the sun is so far away, the amount of pull on the surface of the earth is nearly identical to the pull on the center of the earth. This is not true with the gravity from the Moon because of it's relatively close distance. The moon's gravity pulls hardest on the water closest to it and causes a high tide in that region. The water farthest away from the moon also experiences a high tide because the water and the Earth are pulled towards the moon more than the water at the farthest edge. In between these high tides are low tides for an effect of two high tides and two low tides about every 25 hours. The high tides do not actually follow directly beneath the Moon as the rotation of the Earth causes a slight delay. This delay, in turn, causes a slight forward pull on the Moon that is causing the moon to move away from the earth at about four centimeters per year.
In the Bible, the moon is directly or indirectly referenced 48 times in the Old Testament, 17 times in the Apocrypha, and 10 times in the New Testament.
During the act of creation, Elohim did not just speak, but rather He declared that that something should occur. In the fourth day, Elohim was not creating just any light to exist, but He was declaring for His lights to exist in the Heavens. These lights were to serve His purposes that include separating light from darkness, acting as a calendar, as signals for the festival meetings, and as signs of the time.
As a part of creation, the moon came on the fourth day and was placed in the firmament of heaven along with the sun and the stars. This was after the creation of the earth's land, seas, and plants on the third day and before the creation of animals and mankind on the fifth and sixth days.
The main purpose of the moon, as well as the sun and stars, was to separate the light from the darkness and to give light to the earth. It is the quantity and quality of the moon's light that allows it to serve in all of it's other functions. The moon is referred to as the lesser light because it is the second brightest object in the earth's sky after the sun. Furthermore, the moon was given dominion over the night which is opposite of the daytime which has the sun.
The Almighty has made a covenant with the moon. The moon was given dominion over the night and is referred to as the lesser light which refers to it's being the second brightest object in the earth's sky after the sun.
The sun, moon, and stars were made to act as a calendar. The sun and moon separate the day and the night. The moon is also used to measure the months of the year. This is shown in the Hebrew language as the word for month, chodesh, is the same word used for the new moon. The moon is also used as a reference to the timing of the three annual feasts: the feast of unleavened bread, the feast of weeks, and the feast of booths.
The moon was also made to be a visible sign for great events. Scripture records that during the end times there will be periods when the moon does not shine, when it will shine like the sun, that it will appear as blood, a third part will be darkened, and it will not be needed in New Jerusalem.
There are instructions in Scripture about assembling together and of special burnt offerings being made for the first day of the month (new moon day). Historically, this is an event that is taken away from Israel during times of punishment. In the future, it will be the prince's job to do the offerings. There does not seem to be a stated purpose or commemoration connected with this event.
The moon is a highly visible part of creation. The moon also has some emphasis within Scripture by the number of times it appears in the writings. Because of this, many warnings are given in Scripture about not worshipping the moon. Idolatry in any form is prohibited.