It is all a result of the Moon's orbit around the Earth, and the Earth's orbit around the Sun. And exactly when you see the Moon in the shape of a 'U' (lit on the bottom) rather than a backward 'C' (lit on the side) depends on what latitude you are at.
View the moon in your eastern sky late in the evening this weekend, perhaps before going to bed. It'll be ascending in the east later and later each evening. Then look for it low in your western sky right after sunrise. Day by day, the lighted portion of the waning gibbous moon will shrink.
Only one side of the Moon is visible from Earth because the Moon rotates on its axis at the same rate that the Moon orbits the Earth – a situation known as synchronous rotation, or tidal locking. The Moon is directly illuminated by the Sun, and the cyclically varying viewing conditions cause the lunar phases.
That westward motion is caused by Earth's spin. The moon's orbit carries it around Earth's sky once a month, because the moon takes about a month to orbit Earth. So the moon moves – with respect to the fixed stars – by about 12 to 13 degrees each day. The moon's orbital motion carries it eastward in Earth's sky.
It's not; it's a setting moon. As Earth spins under the sky, all sky objects rise in the east and set in the west. A waxing crescent moon – visible in the western sky – follows the sun below the western horizon. It's caused by light reflected from Earth's day side onto the moon.
The moon's orbit carries it around Earth's sky once a month, because the moon takes about a month to orbit Earth. So the moon moves – with respect to the fixed stars – by about 12 to 13 degrees each day. The moon's orbital motion carries it eastward in Earth's sky. Image via cseligman.com.
Lunar calendar for 2020
| New Moon | First Quarter | Full Moon |
|---|
| Apr. 22, 22:26 p.m. | Apr. 30, 4:38 p.m. | May 7, 6:45 a.m. |
| May 22, 1:39 pm. | May 29, 11:30 pm. | Jun. 5, 3:12 p.m. |
| Jun. 21, 2:41 a.m. | Jun. 28, 4:16 p.m. | Jul. 5, 12:44 a.m. |
| Jul. 20, 1:33 p.m. | Jul. 27, 8:32 a.m. | Aug. 3, 11:59 a.m. |
The Moon is only visible at night. We frequently see the Moon in the day; the only phases of the Moon that cannot be seen in the day are full moon (which is usually only visible at night) and the new moon (which is not visible from Earth at all). The Moon becomes larger on the horizon because it is closer to Earth.
As a result of the Moon's synchronous rotation, one side of the Moon (the "near side") is permanently turned towards Earth, and the other side, the "far side", mostly cannot be seen from Earth.
In the case of the Moon illusion, objects in the vicinity of the horizon Moon (that is, objects on or near the horizon) exhibit a fine detail that makes the Moon appear larger, while the zenith Moon is surrounded by large expanses of empty sky that make it appear smaller.
As others have pointed out, you can “see” the spinning of the Earth by watching the stars rotate around a point close to the North Star. The spinning of the Earth also reduces the amount you weigh when you travel to the Equator, due to the centrifugal force of the spin.
For the moon to be visible during the day, it must be up in the sky at the same time as the sun, but not so close to the sun in the sky that you can't see it. The full moon rises at sunset, is up all night, and sets at sunrise, so you can't see a full moon in the daytime.
The time it takes the Moon to rotate on its axis is the same time it takes to complete one trip (or “orbit”) around the Earth. This is why we always see the same side of the Moon. It also follows a similar path across the sky as the Sun.
It takes almost the same amount of time to make one rotation on its axis. That is why we always see the same side of the Moon from Earth. This part of the Moon is not really the "dark side", however, it is more accurately the "far side".
In Australia, the Moon is "upside down" from the point of view of northern hemisphere viewers.
The moon rises in the east and sets in the west, each and every day. It has to. The rising and setting of all celestial objects is due to Earth's continuous daily spin beneath the sky.
Tidal forces from Earth have slowed down the Moon's rotation to the point where the same side is always facing the Earth—a phenomenon called tidal locking. The other face, most of which is never visible from the Earth, is therefore called the "far side of the Moon".
Why does the Moon look upside down from Australia? It's because we're on a spherical planet. If I stand at the North Pole, with my head “up,” and have a friend stand on the South Pole, with their head “up,” relative to the ground, our two heads are pointed in exactly opposite directions.
The lunar month is the 29.53 days it takes to go from one new moon to the next. During the lunar month, the Moon goes through all its phases. We only see the Moon because sunlight reflects back to us from its surface. During the course of a month, the Moon circles once around the Earth.
As with most lunar eclipses, the moon appeared red during the April 15, 2014, eclipse. The red color is caused by Rayleigh scattering of sunlight through the Earth's atmosphere, the same effect that causes sunsets to appear red.
The moon shines because its surface reflects light from the sun. And despite the fact that it sometimes seems to shine very brightly, the moon reflects only between 3 and 12 percent of the sunlight that hits it. The perceived brightness of the moon from Earth depends on where the moon is in its orbit around the planet.
The different shapes of the lit portion of the Moon that can be seen from Earth are known as phases of the Moon. Each phase repeats itself every 29.5 days. The same half of the Moon always faces the Earth, because of tidal locking. So the phases will always occur over the same half of the Moon's surface.
The full moon occurs roughly once a month. The time interval between a full (or new) moon and the next repetition of the same phase, a synodic month, averages about 29.53 days.
Sometimes when the moon orbits Earth, it moves between the sun and Earth. When this happens, the moon blocks the light of the sun from reaching Earth. This causes an eclipse of the sun, or solar eclipse. During a solar eclipse, the moon casts a shadow onto Earth.
When the Sun, Earth, and the Moon are aligned perfectly (or nearly so), with Earth between the Sun and the Moon, Earth's shadow falls onto the lunar surface facing the night side of the planet, such that the shadow gradually darkens the full Moon, causing a lunar eclipse.
Answer: Yes, the Sun - in fact, our whole solar system - orbits around the center of the Milky Way Galaxy. We are moving at an average velocity of 828,000 km/hr. But even at that high rate, it still takes us about 230 million years to make one complete orbit around the Milky Way!
The (fairly) simple answer
The Moon rises and sets every day, like the Sun. But the Sun always rises in the morning and sets in the evening; the Moon does it at a different time every day.Moonrise happens when the Earth has rotated enough on its own axis that the Moon has appeared in your personal sky - your horizon has caught up with the Moon. When exactly that happens is a combination of the Earth's rapid rotation, and the Moon's continual motion through the skies.
