The moon - Research Paper Example

The Moon affiliation The Moon One of the uniqueness of the earth among the terrestrial planets is the fact that it hasa large satellite, also called the moon. The moon in relation to the earth, has the largest mass when it comes to comparing it to any other satellite-parent in existence (Astronomy Today, 2014). A number of evidences have proved that the moon was formed from the earth as a result of an impact that occurred soon after the earth was formed. Due to this, the moon has been key in the process of the earth’s evolution, and the appearance and development of life on earth. Billions of years ago, a body the size of Mars, also known as Theia, crashed into a very young earth causing a near disaster. The parts that fragmented from this impact came together to form what is now seen as the moon (Howell 2014). A recent study by scientists upon a rock drawn from Apollo mission on the moon shows some evidence of this occurrence. The new research shows isotopic differences between the moons rock and those from the earth. The importance of this development is that it shows that a body of different composition must have caused the difference. If the moon came from Theia which is different from the earth, then the composition must be different. The scanning was done on samples from three Apollo missions 11, 12 and 16 with electron microscopes that are way better than what was used in the 60s and 70s when scientists took a first look at the rocks. By then, the microscopes could not allow them to detect any significant differences. The recent findings have it that the moon has 12 parts per million-17 greater oxygen content than that of the earth (Henney 2014). One of the most obvious effects of the moon on earth is the presence of ocean tides, especially the spring tides which occur when the gravitational pulling of the earth combines with that of the moon to cause the highest rise. The rise of the sea and the fall of the same have major effect of sea life as life is exposed to air and dipped in water in a matter of hours. This shift is thought to be a major influence to evolution. The moon also has an effect on the rising tides of solid bodies on earth. In the past due to the earth’s closers distance to the moon that it is current, these tides have led to displacements of up to a kilometre away (astronomy today 2014). Phases of the moon Phases simply mean that when the moon goes around the earth it shows different amount of light at different times. Cycles refer to the fact that these phases and those of eclipses occur repeatedly. To understand the phases a basic understanding of how light and shadows behave particularly related to the light of the sun, the orbit of the moon and that of the earth around the sun is necessary. The study of the moon phases opens up to an understanding of a scientific explanation such occurrences in astronomy. The moons motion It is important to first note two things that occur during the moons motion around the earth as it is observed night after night, it moves towards the east in front of the stars and it constantly shows one face towards the earth in every phase that occurs. The moons motion around the earth is quite fast as it moves approximately 0.5 degrees in one hour, bringing to a total of about 13 degrees in 24hours. This motion of the moon around the earth showing just one face throughout is as a result of the moon moving along its orbit. This occurrence is not a coincidence but a result of tidal coupling between the earth and the moon. The distance between the earth and the moon is approximately 60 times the earth’s diameter, just about 384, 000 kilometres. The orbiting of the moon is counter clockwise to the earth. The moons orbit is a bit elliptical and at some point the distance from the earth varies by 6%. The period of the orbit is about 27.3 days and is known as sidereal period or sidereal month, which is measured with reference to background stars. It takes the moon on sidereal period to make a complete cycle. During its eastward motion the moon sticks around the elliptic, being tipped at 5 decrees 9 arc seconds to the earth’s plane around the sun as the earth is also tilted by the same amount to the elliptic. This simply implies that the moon also shows a trace of zodiac as it moves along the sky given its move from the elliptic on the sky, this is because its orbit is too small (Rochester edu 2014). Lunar phases and phase cycle The moon does not produce its own light, but that which is seen from it is just what it reflects from the sun. As it moves around the sky, the suns light is illuminates at different amounts. What determines the phase of the moon is basically related to the earth’s position in relation to the sun. It appears to be going through a complete set of phases as it goes around the earth, as seen from the earth. The term quarter in relation to the moons phase does not refer to how much of the moon can be seen but the phase in which it is in. A complete lunar cycle takes 29.5 days and is called synodic period. This is longer than the sidereal period: the moon goes back to the exact spot every sidereal period, but during this time the sun is also moving on the sky and by the time the moon completes a sidereal cycle the sun has moved by 27 degree meaning the moon must catch up. It takes the moon about two days to catch up with the sun. The complete set of phases in a cycle include: the new moon, waxing gibbous, first quarter, waxing gibbous, full moon, warning gibbous, third quarter, waxing gibbous and finally back to the new moon (Rochester edu 2014). Eclipses There are two types of eclipses, the lunar and the solar eclipse. Lunar eclipse occurs when the moon passes through the earth’s shadow while the solar eclipse happens when the earth passes through the moons shadow. Because the sun appears as a disk the shadows produced by its light are fuzzy and not sharp. This makes the shadows formed by the earth and the moon to be in two parts: umbra and penumbra. The umbra is formed as the inner part of the shadow where there is total darkness as the suns light is totally blocked, while the pen umbra is formed in the outer circle where the suns light is not full blocked as there are bits peeking on the sides. These occur during full moon only at the time when the earth is between the sun and the moon. Due to the scattering of the suns light by the earth’s transparent atmosphere, the earth’s penumbra is not totally dark, giving the moon a ruddy look (Richard 2014). There are three types of lunar eclipse: penumbra, total and partial. In the penumbra the moon misses the umbra totally as it passes through the penumbra, while in the total the moon is within the umbra of the earth and the partial just a part of the moon reaches the umbra (Richard 2014). Solar eclipse takes place when the earth passes through the moons shadow. This takes place only during the new moon when the moon is between the earth and the sun. Just as same as the lunar eclipse, there are three types of solar eclipses: annular, total and partial. In the annular the moon is in the near apogee making it too small to cover the sun complete. The, moons umbra does not touch the earth. For the partial the observer is within the moons penumbra and can only seen part of the sun that is covered by the moon. For the total, the observer is insider the moons umbra as the moon completely covers the sun (Richard 2014). The moon was formed when the Mars-like body Theia collided with the earth. The fragments late coalesced to form the moon. The moons effect that is commonly known is the ocean tides as a result of gravitational pull between the earth and the moon. The moon goes around the earth in a cycle called the sidereal period that takes approximately 27.3 days. There are two types of eclipses, the lunar and the solar. The solar eclipses are of three types annual, total and partial while types of lunar eclipses are penumbra, total and partial. References Richard P (2014) An Introduction to Solar System Astronomy. Lecture 9: Eclipses of the Sun & Moon. Retrieved from http://www.astronomy.ohio- state.edu/~pogge/Ast161/Unit2/eclipses.html Rochester edu. (2014) Orbit and Phases of the Moon. Retrieved from http://www.pas.rochester.edu/~blackman/ast104/moonorbit.html Howell E. 6 june 2014. Hulk Smash! Collision That Formed Our Moon Shows Up In Lunar Rocks, Study Says. Retrieved from http://www.universetoday.com/112418/ hulk-smash-collision-that-formed-our-moon-shows-up-in-lunar-rocks- study-says/#ixzz348d0BZnI Henney P J. (2014) How Earth and the Moon interact. Retrieved from http://www.astronomytoday.com/astronomy/earthmoon.html Read More