You will never see a crescent moon during sunrise and before sunset because the moon rises and sets with the sun and when the crescent moon is visible, it is typically seen later in the evening or early in the morning.
full moon
The dark circle (new moon)
I don't think there is one. It's possible, though rare, for the moon to be full just after sunrise or just before sunset ... this happened recently in Southern California, when there was a lunar eclipse visible right about the time of sunrise. Lunar eclipses can only occur when the moon is full. (Technically, the moon wasn't "full", exactly; that had occurred a few hours before ... but it was so close that the difference was unnoticeable to the naked eye.)
For two antipodal locations (on opposite sides of the Earth) it will be sunrise for one when it is sunset for the other.Also, on the winter solstice, areas very near the North Pole or South Pole may experience a "day" of only a few minutes length, with sunrise quickly becoming sunset and the Sun never leaving the horizon. At the Poles themselves, the period from sunrise to sunset, and sunset to sunrise, is 6 full months.
No, it is not possible to see the sunrise and sunset at the same place in a single day. The sun rises in the east and sets in the west due to the Earth's rotation. However, during certain times of the year in polar regions, there may be phenomena like the midnight sun where the sun is visible at midnight, but this is not simultaneous with sunset.
I don't think there is one. It's possible, though rare, for the moon to be full just after sunrise or just before sunset ... this happened recently in Southern California, when there was a lunar eclipse visible right about the time of sunrise. Lunar eclipses can only occur when the moon is full. (Technically, the moon wasn't "full", exactly; that had occurred a few hours before ... but it was so close that the difference was unnoticeable to the naked eye.)
The Full Moon is opposite the Sun in the sky and therefore it rises as the Sun sets and sets as the Sun rises. (Actually, near the Earth's poles in summer, you can see the Full Moon during daylight.) You can never see the New Moon either because it is in line with the Sun and hidden by glare. (You can see the New Moon in the daytime, but only when there is a solar eclipse.)
They could use the sunrise/sunset to find north - or the stars.
You will never see Mercury on a dark sky. The reason is that Mercury is the closest planet to the Sun, and so we can only see it shortly before sunrise or shortly after sunset. The sky is always still fairly light.
The exact times of sunrise and sunset vary by location and date, but generally speaking: in spring, sunrise tends to occur earlier and sunset later; in summer, sunrise is earlier and sunset is later; in fall, sunrise is later and sunset is earlier; and in winter, sunrise is later and sunset is earlier.
This questions is wrong, the sun does rise and set on Uranus. Because on its large tilt, many areas of the planet will have a very long night during their winter, and a very long day during the summer, similar to the poles on Earth. However, during the spring and fall, the whole planet will have regular sunrise and sunset.
He never really understood the poem until he saw the sunset.