It also takes about 27 days for the moon to rotate on its axis. So, the moon always shows us the same face; there is no single "dark side" of the moon. As the moon revolves around Earth, it is illuminated from varying angles by the sun — what we see when we look at the moon is reflected sunlight.
On average, the moon rises about 50 minutes later each day, which means sometimes it rises during daylight and other times at night. At new moon, the moon is between Earth and the sun, so that the side of the moon facing toward us receives no direct sunlight, and is lit only by dim sunlight reflected from Earth. A few days later, as the moon moves around Earth, the side we can see gradually becomes more illuminated by direct sunlight.
This thin sliver is called the waxing crescent. A week after the new moon, the moon is 90 degrees away from the sun in the sky and is half-illuminated from our point of view — what we call first quarter because it is about a quarter of the way around Earth. A few days later, the area of illumination continues to increase. More than half of the moon's face appears to be getting sunlight. This phase is called a waxing gibbous moon. When the moon has moved degrees from its new moon position, the sun, Earth and the moon form a line.
Next, the moon moves until more than half of its face appears to be getting sunlight, but the amount is decreasing. This is the waning gibbous phase. Days later, the moon has moved another quarter of the way around Earth, to the third quarter position. The sun's light is now shining on the other half of the visible face of the moon. Next, the moon moves into the waning crescent phase as less than half of its face appears to be getting sunlight, and the amount is decreasing.
Finally, the moon moves back to its new moon starting position. Usually the moon passes above or below the sun from our vantage point, but occasionally it passes right in front of the sun, and we get an eclipse of the sun. Each full moon is calculated to occur at an exact moment, which may or may not be near the time the moon rises where you are.
In fact, the moon will often look roughly the same on two consecutive nights surrounding the full moon. Lunar eclipses are inextricably tied to the full moon. When the moon is in its full phase, it is passing behind the Earth with respect the sun and can pass through Earth's shadow, creating a lunar eclipse. When the moon is fully inside the Earth's shadow, we see a total lunar eclipse. At other times, the moon only partially passes through the Earth's shadow in what is known as a partial, or even penumbral lunar eclipse when the moon only skirts through the outermost region of Earth's shadow.
Once the Sun rises, it is not easy to see this slim phase; the best time is before the glare of sunrise. The term " Moon's age " is not a reference to how long the Moon has existed about 4. As mentioned above, the span of time between one new Moon and the next is called a lunar cycle , lunation , lunar month , or synodic month and on average lasts for This translates to 29 days, 12 hours, 44 minutes, and 3 seconds. The length of a lunar cycle can vary by more than 13 hours due to a few factors.
When the new Moon phase occurs at about the same time as apogee when the Moon is farthest from Earth , longer lunations result. This is related to the fact that the Moon travels faster in its orbit at perigee and slowest in its orbit at apogee. The longest lunations result when the new Moon coincides with apogee and Earth is at perihelion.
The shortest lunations result when the new Moon coincides with perigee and Earth is at aphelion. One of the shortest lunations was 29 days, 6 hours, and 35 minutes, whereas one of the longest was 29 days, 19 hours, 55 minutes. Note: The synodic month describes the time for the Moon to complete one orbit around Earth and return to the same position relative to the Sun and Earth. If Earth were not moving along in its orbit but instead were standing still, the Moon would take less time to reach that same position: This is called the sidereal month , which is about 2.
Looking at the calendar on this page, you can see that from new to full, the percentage increases, indicating the waxing stages, and from full to new, the percentage decreases, indicating the waning stages. The New Moon is 0 percent illuminated or totally dark ; First Quarter is essentially 50 percent illuminated half of the disk is lit ; Full Moon is percent illuminated the entire disk is lit ; and Last Quarter is back to essentially 50 percent illuminated half of the disk is lit.
The Moon is exactly half-lit when it reaches dichotomy , which occurs several minutes before first quarter and several minutes after last quarter. Below are general guidelines as to where to look for the Moon during each of its phases. Times mentioned are solar time, not clock time. The four primary phases in italics rise and set at a point in time; the four secondary phases occur over a broader timespan.
It occurs when light travels from the Sun to Earth, reflects off the Earth, travels to the Moon, and then bounces back to Earth to reach our eyes. Fun fact: the word Gibbous was first used in the 14th century and comes from the latin word gibbosus which means humpbacked. Want to view the moon phase for a specific date?
Use the handy calendar below to find any date you like and see what the current phase of the moon was for that date. Below are the upcoming moon phase dates and times. For more information on each of the phases, you can click the link to find out more.
Home Membership Teacher Worksheets. Moon Phase for Today Information about the current phase of the moon, and upcoming phases for today.
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