Dusk is the darkest stage of twilight, or the very end of astronomical twilight, occurring after sunset and just before nightfall. At mid-northern latitudes, dusk begins when the sun is about 6 degrees below the horizon. The period of dusk lasts for about an hour, during which time some stars may become visible in the west. Eventually, more stars appear, until completely dark conditions prevail.
Sunset is the moment at which the Sun reaches its lowest point on the horizon. This occurs around an hour after dawn and can be recognized by the beginning color in the sky as well as a decrease in the intensity of sunlight. Sunset is important because it signals the end of daytime activities such as work, school, and shopping. It also marks the end of an entire day, which requires planning for the next morning's activities.
From one sunset to the next, there is a period of twilight between them. During this time, both sunset and dusk occur. They differ only in degree, with dusk being slightly darker than sunset. The length of this period varies depending on the season and location. In summer, when the days are long, the period can last several hours; but in winter, when the nights are longer, it can be less than an hour.
Near pre-dusk, throughout the early to middle phases of twilight, there may be enough light in the sky to read outdoors without artificial illumination, but at the conclusion of civil twilight,...
Dusk occurs less frequently than twilight because most cities and towns do not have a horizon line that marks the transition from day to night. Instead, they have an urban glow that extends for many miles around large cities at night.
Cities and towns across the world will experience a new dawn tomorrow morning at approximately 5:30 a.m.Eastern Standard Time (EST). The last bit of twilight will disappear when daytime enters a new season, spring. While it may not seem like much, this is actually a significant astronomical event that needs to be recognized by science enthusiasts and novices alike. Astronomers use the term "astronomical midnight" to describe the time of year when the sun is neither rising nor setting.
During astronomical dusk and midnight, only the brightest stars can be seen with the unaided eye, although faint stars are visible with a small telescope. Sights of the night sky are influenced by atmospheric conditions such as humidity, cloud cover, and dust. As clouds pass over the moon or planets, they block out some of the light from these bodies, causing a dark area on the lunar surface or in a planet's orbit.
After the sun's rays have passed the horizon, it is called dusk. There is astronomical dusk, nautical dusk, and civil dusk, which occur at 18 degrees, 12 degrees, and 6 degrees below the horizon, respectively. The night sky becomes more visible as the night progresses because of the absence of sunlight. Soon after sunset, the first stars appear with Venus, the Evening Star, lying directly above the western horizon. As the night progresses, Mars, the Red Planet, rises over the eastern horizon.
The Milky Way appears across most of the night sky but is especially bright near sunrise or sunset when it resembles a river running through the center of the galaxy. The North Star provides direction in the morning and south star in the evening. Other stars include the Big Dipper, Cassiopeia, Leo, Orion, Perseus, Sagittarius, and Scorpius.
In conclusion, there are many interesting things about dusk: it is the time when people around the world stop work for the day; it is also the time when animals seek out shelter from the approaching darkness; lastly, it is the time when science-fiction movies usually start their sequels.
Twilight Twilight, in its broadest definition, is the period of time between dawn and sunset when the atmosphere is partially lighted by the sun but is neither entirely dark nor completely bright. This period begins when twilight ends and lasts for an hour or more depending on the season and location around the world.
It is called twilight because during this time, things appear to be in a state of change or transition from one thing to another; from dark to light or vice versa. Thus, twilight can be used to describe any phase of transition or degree of darkness and lightness. For example, when something enters a room through an open door or window, it first becomes visible in the darkness before being illuminated by sunlight outside. Then, once it is fully exposed to daylight, it can be seen in its full brilliance.
In science, astronomy and photography, twilight is the name given to the period of time immediately following sunrise or before sunset. During this time, the sky is gradually coming out of darkness and beginning to take on a pale color as morning or evening clouds begin to rise or descend, respectively.
The word "twilight" is also used in reference to other periods of transition or degree of darkness and lightness.
Twilight, in its broadest definition, is the period of time between dawn and sunset when the atmosphere is partially lighted by the sun but is neither entirely dark nor completely bright. However, this general description leaves many questions open, such as what time does twilight start and end? What part of the day is it when twilight starts and ends? What color is the sky during twilight? These and other related questions are discussed here.
In most parts of the world, twilight begins just a few minutes after sunrise and ends shortly before sunset. However, in some regions such as Antarctica, where there is no daytime summer season, twilight lasts all day every day. In these cases, twilight is said to be 24-hour.
The length of twilight is determined by the distance of the observer from the horizon. An observer on the ground will see less twilight than one at an altitude because of the difference in distance between the two points. The closer an observer is to the horizon, the shorter their observation of twilight will be. For example, an observer on the ground will see only half of the moon's orbit before it sets while someone standing in a window would see it rise again after it has gone down.
Color photography uses filters to restrict the response of the camera's sensor or film to certain wavelengths of light.
However, there are three types of twilight based on how far the sun lies below the horizon. Nautical twilight ends when the altitude of the sun reaches 10 degrees below the horizon. Astronomical twilight ends at midnight. Daytime twilight ends when the sun reaches its highest point in the sky which is around 12 o'clock in mid-summer.
Civil twilight ends about an hour later if there's no moon out. The length of civil twilight varies with season and location within the United States. In winter, it can be as long as two hours in the central part of the country while in summer it can be as little as 30 minutes near the poles. Outside of the US and Canada, civil twilight lasts for only a few minutes at most so don't worry about it during your daily travels.
Meteorological twilight ends when night falls and begins when morning breaks so they always occur at the same time. During meteorological twilight, the darkness of space isn't interrupted by sunlight even though it may seem like it from Earth because stars such as our moon and planets come into view.
Astronomical twilight doesn't last long enough to see any celestial objects besides the moon and planets but scientists use this phenomenon to determine their location on Earth.