Hobbies And Interests
Earth-Moon Relationship
The moon's orbit is not quite circular; at its nearest point to the Earth, called the perigee, it is about 25,000 miles. closer to the Earth than at apogee, the farthest point. The moon's path also is tilted. It does not follow Earth's equator, the imaginary line that travels around the planet's center.
Sun-Moon Relationship
The moon does not emit light. It reflects the sun's light, except during a lunar eclipse when the Earth is between the sun and the moon, casting a shadow.
Phases of the Moon
Except during an eclipse, one side of the moon is bathed in sunlight. Sometimes we can see the side that's illuminated, and sometimes we cannot. Often, we see a crescent moon of varying thickness. The four major phases of the moon are new moon, half moon, full moon and half moon.
During the new moon phase, the side of the moon that is reflecting the sun's light is away from us. No light is seen from Earth because the dark side of the moon is facing Earth. A half moon occurs when half of the lighted side can be seen in the night sky. During a full moon, the bright side faces Earth.
Phase Changes
The amount of reflected light seen depends on where the moon is during its trip around the Earth. When a new moon becomes a sliver of a crescent, it is "waxing." The waxing crescent grows to a quarter moon or half moon and continues growing until the entire sunlit side is turned toward the sun, creating a full moon.
After a full moon, the moon is "waning." Waning is the steady decrease in the size of the moon to half and then to various crescents, until just a sliver of light is seen.
A Blue Moon
A blue moon refers to a second full moon occurring within the same month. Although rare, these moons happen because the orbit of the moon does not match with the civil calendar. These mismatched days accumulate, and the full moon is reached progressively earlier in the month until two full moons occur in the same month, once at the beginning of the month and again at the end.