The Moon

The Moon is a celestial astronomical satellite that orbits the Earth. The moon is the fifth largest body in the solar system, and it has the second highest density. The moon is around 3.84 thousand kilometers from Earth and is believed to have evolved 4.51 billion years ago from debris left behind from the Earth-Theia collision.

As seen through a binocular, large-scale lunar features such as the Maria patterns and highlands are visible. As the moon crosses through the terminator of the binoculars, the shadows of mountains and other physical features can be used to show the phases of the moon. For instance, the lighter and darker surfaces are visible at full moon indicating that the relief has disappeared. The naming of the visible features started during the time of Galileo who used to make sketches, which were later utilized by the astronomers to carry out mapping of the critical attributes of the moon using the telescopes through the surface. The possibility of visiting the moon came up in the 20th Century, and in the 1960s, the US Air Force sponsored the publication of the first Atlas showing the visible features of the Moon. The effects of the topographical characteristics of the Moon such as the Volcanism were clarified in the 20th Century and this idea was backed up by the fact that the collisions between large bodies can lead to the formation of the highlands. The Marias is evidence of the fluid lavas. The missions by various scientists to the moon have also indicated that the hidden parts of the Moon are scarred by basins which are unlike the other side not filled with lava.

The Volcanism Activities in the Moon.

The lunar scenes reveal the impacts of volcanism. For instance, a basin by the name Oriantale exists in the west Lunar Lon of the moon, and the feature is believed to have been as a result of the lunar-mapping which occurred between 17th-19th Centuries. The other features formed from small impact are termed as craters whose ages can be based on their forms and structures. The craters’ attributes can also show the information on how the impact happened. The crater has a cup-shaped cavity which is not stable, and therefore can easily evolve into another feature by the name Aristarchus which has slumping terraces. Other peculiar lunar features are found in the region around the Aristarchus. The examples of such features include Oceanus Procellarum, sinuous rille, Schröter’s Valley, Reiner Gamma, crater rays, among others.

Through the measurements of the seismic and heat flow, it is apparent that volcanic activity is lower as compared to that of the earth. Such measurements even though smaller indicate that there are the interactions between the lunar surface and the volcanic emissions, which consequently leads to the formation of the clouds. However, the level of activity of the moon is a question that is still open for discussion. The moon also shows tension and compression features which are as a result of the branching and sinuous rilles around the Alphonsus. Stress leads to eruption craters, while compression results into the mare margins. There is, however, no evidence to show that the Moon had also experienced the high, lateral motions witnessed on the earth as put by the plate tectonic theory.

The other small-scale features

A combination of the impact effects due to arrival and the solar flare governs the properties of the lunar surface. The entry effects speed up the meteoritic materials, while the solar flare particles ionize the radiations. In the process, the top-most part of the regolith insulates the moon since it is highly porous. The observation of the regolith surface was initially possible, and that made the Moon's surface unique. The photometry studies indicate that the moon is brighter on the bright side; while the polarization aspects of the reflected light show that the surface is rough. The depth of the regolith layer could not be measured until man landed on the moon. The characteristics of the outer surface were outlined based on the conclusions from the thermal observations. The lunar surface cools when the shadow of the earth falls past the Moon during the lunar eclipse phenomenon, and this is an indication that the insulation layer is shallow.

The Lunar rocks and soil.

The regolith layer of the lunar surface has both igneous rocks and soil. In the Maria, breccias are the common types of rocks found, and the massive bedrocks have never been found on the moon. On the other hand, the lunar soil originates from the lunar rocks, and they possess a distinctive character in that the soil is a representation of the typical micrometeoroid bombardment in the Moon’s surface. The agglutinate fraction of the lunar soil is a measure of maturity. The chemical and mineral contents together with the presence of the solar wind particles of the soil indicate that it must have been formed as a consequence of the impact between two colliding bodies. The mineral and chemical properties can also be used to guess the Moon’s history. The moon has the lunar mantle and crust, which are made up of the minor minerals that are grouped into four categories namely: basaltic volcanic, pristine highland rocks, breccias and impact melts, the soils and all of these trace their origin from the igneous rocks.

The Lunar Interior

Most information about the lunar interior originated from the Apollo missions from which the moon was portrayed to comprise of a crust of low density, overlaying mantle, and a metallic core at the center. The core has magnetic properties, as can be shown from some of the lunar rocks, while the crust is asymmetrical. Moreover, the available compositional data indicates that the internal activities before and after the discoveries are a bit different due to the heating and cooling events that might have possibly driven out the highly volatile materials, hence erasing the data records on the same. From the earthquakes, it can be shown clearly from the seismic waves recorded that there is a distinction between the regolith layer of the lunar surface and that of the Earth.

The Origin and Evolution

The studies about the Renaissance period excited the investigations onto the theories regarding the moon’s origin and evolution. One of the approaches involved the use of mathematically based examinations to establish the Earth-Moon systems. After a long duration, conclusions states that the Moon gradually recedes from the Earth and that the rotation of the moon and the earth are slowing down. Some theories explain the origin of the Moon, and they are categorized into three: the fission, capture, and coaccretion, and after another century of study, the scientists agreed to the fact that the Moon must have originated from the giant-impact hypothesis. On the other hand, the moon has evolved in stages from the proto-moon formed from the debris cloud (according to the giant-impact model) to a solar system constituent where only little weathering; solar, cosmic radiation and particles are eminent.

Lunar Explorations and Mission Results

The investigations of the Moon started many years ago with the earliest studies being done in the ancient China and the Middle East. In both cases, the observations could be used to make predictions on the eclipses, something that provided the foundations for tracing the history of the Moon, and the development of the Mayan Calendars. Serious studies were done during the Renaissance periods where the factors regarding astrology and navigation became the driving force. Because of the need to explore the Moon, the first robotic missions were carried out in the year 1957 by the Russians using the first ever spacecraft. The attempt by the USSR did not succeed but instead initiated the space exploration programs. The US had a more ambitious program that saw the establishment of the Ranger programs in 1961-65, as the Soviet States was engaged in the Apollo mission.

After more than two decades of ambitious attempts and success by the United States, the space exploration programs made a revolution on the how people understood the moon. Up to date, scientists still study the samples collected during that period, and the data is now useful as a radiometric age dating items for the survey of the rocks and soil that makes up the moon.