the_moon

the_moon - THE MOON MOON From From any location on the...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: THE MOON MOON From From any location on the Earth, the Moon appears to be a circular disk which, at any specific time, is illuminated to some degree by direct sunlight. Like the Earth, the Moon is a sphere which is always half illuminated by the Sun, but as the Moon orbits the Earth we get to see more or less of the illuminated half. of During During each lunar orbit (a lunar month), we see the Moon's appearance change from not visibly illuminated through not partially illuminated to fully illuminated, partially fully then back through partially illuminated to partially not illuminated again. Although this cycle not is a continuous process, there are eight distinct, traditionally recognized stages, called phases. The The phases designate both the degree to which the Moon is illuminated and the geometric appearance of the illuminated part. These phases of the Moon, in the sequence of their occurrence (starting from New Moon), are listed below. from 1. New Moon 1. The The Moon's unilluminated side is facing the Earth. The Moon is not visible (except during a solar eclipse). eclipse). 2. Waxing Crescent 2. The The Moon appears to be partly but less than one-half illuminated by direct sunlight. The fraction of the Moon's disk that is illuminated is increasing. is 3. First Quarter 3. One-half One-half of the Moon appears to be illuminated by direct sunlight. The fraction of the Moon's disk that is illuminated is increasing. increasing. 4. Waxing Gibbous 4. The The Moon appears to be more than one-half but not fully illuminated by direct sunlight. The fraction of the Moon's disk that is illuminated is increasing. increasing. 5. Full Moon 5. The The Moon's illuminated side is facing the Earth. The Moon appears to be completely illuminated by direct sunlight by 6. Waning Gibbous 6. The The Moon appears to be more than one-half but not fully illuminated by direct sunlight. The fraction of the Moon's disk that is illuminated is decreasing. decreasing. 7. Last Quarter 7. One-half One-half of the Moon appears to be illuminated by direct sunlight. The fraction of the Moon's disk that is illuminated is decreasing. decreasing. 8. Waning Crescent 8. The The Moon appears to be partly but less than one-half illuminated by direct sunlight. The fraction of the Moon's disk that is illuminated is decreasing. is ...
View Full Document

This note was uploaded on 11/29/2011 for the course PHYS 122 taught by Professor Terry during the Fall '11 term at BYU.

Ask a homework question - tutors are online