Astronomy assignment - Essay Example

Phases of the Moon The relationship between the Sun, the planets which in this case orbit the sun, their satellites and many other small objects like comets and asteroid make up the solar system. All the objectives in the solar systems moves around the sun as can be justified by different observable movements. Such movements include the fact that the sun rises in the morning from eastern sky and sets in the evenings at the western sky. Some different stars can also be observed at different times of the year.

Moreover, the moon can be seen at different dates of the month. In this paper, however, a discussion will be based on the phases of the moon and as a focus on position of other bodies is included.It is a fact that moon does not produce its own light but only acts as a reflector of the sun’s lights. One can observe different parts of illuminated moon by the sun as it moves around the sun. This is the reason why the moon changes its shape in time and regularly. This observations where moon changes its shape in time is called the phases of the moon.

As the moon moves around the earth, its one side is illuminated and changes in time from dark to fully lit and henceforth. When the moon is fully lit, it’s said to be in lunar phase (Pamela, 1996, Web) where one observes a full moon on the side facing the earth. This phase only appears when the earth positions itself between the sun and the moon where the moon reflects the lights of the sun directly to the earth. The moon the enters the quarter moon phase in about a week later and is seen as half since the visible lit portion is half by somebody on earth.

When the moon moves between the earth and sun, one observing it from the earth sees a complete dark surface since at this time it’s reflecting the lights back to the sun. The complete darkness is seen at different parts since the moon itself is not transparent and blocks the lights from the sun. Although some of the lights surpasses it and directly hit the earth as the moon is smaller than the size in terms of size. This occurrences is called the new moon phase. Before and after the quarter phases of the moon, there are crescent and gibbous phases.

In crescent phase, the moon surface as reflected on earth is less than half lit. Whilst in gibbous phase, the moon surface viewed on earth is more that half, but not full lit. The moon’s revolution around the earth makes it to appear like it is changing its shape. But the fact is that, it is caused by the different angles by which, it is observed on its lit-surfaced side. As shown on the diagram below, the moon’s cycle or change of the phases is a continuous process where it changes constantly.

It never stops its movement at any given phase and starts from day one as a new moon and ends on day 29 as a dimming crescent. It is also good to note that the moon reaches the major phase after every 7 days after the occurrence of the new moon. The quarter moon, which is the first to occur, appears after about 7.4 days. The crescent moon also occurs between the new and the first quarter. Then the full moon appears in about 14.8 days before which the gibbous phase occurs. Then the waning state starts to occur immediately after the full moon until the 29th day when the cycle starts again.

Works Cited Pamela, Gore. Phases of the Moon. Georgia Perimeter College, Jan 01 1996. Available at: http://facstaff.gpc.edu/~pgore/astronomy/astr101/moonphas.htm. Retrieved on: March 15 2013