Great Fountain Geyser - 1

Sunset or sundown is the daily disappearance of the Sun below the western half of the horizon, i.e. at an azimuth greater than 180 degrees, as a result of Earth's rotation.

The time of sunset is defined in astronomy as the moment when the trailing edge of the Sun's disk disappears below the horizon. The ray path of light from the setting Sun is highly distorted near the horizon because of atmospheric refraction, making the sunset appear to occur when the Sun’s disk is already about one diameter below the horizon. Sunset is distinct from dusk, which is the time at which the sky becomes completely dark, which occurs when the Sun is approximately eighteen degrees below the horizon. The period between sunset and dusk is called twilight.

Locations north of the Arctic Circle and south of the Antarctic Circle experience no sunset or sunrise at least one day of the year, when the polar day or the polar night persist continuously for 24 hours.

Sunset creates unique atmospheric conditions such as the often intense orange and red colors of the Sun and the surrounding sky.

Yellowstone National Park (Arapaho: Henihco'oo' or Héetíhco'oo) is a national park located primarily in the U.S. state of Wyoming, although it also extends into Montana and Idaho. It was established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872. Yellowstone, widely held to be the first national park in the world, is known for its wildlife and its many geothermal features, especially Old Faithful Geyser, one of the most popular features in the park. It has many types of ecosystems, but the subalpine forest is dominant.

Native Americans have lived in the Yellowstone region for at least 11,000 years. The region was bypassed during the Lewis and Clark Expedition in the early 19th century. Aside from visits by mountain men during the early-to-mid-19th century, organized exploration did not begin until the late 1860s. The U.S. Army was commissioned to oversee the park just after its establishment. In 1917, administration of the park was transferred to the National Park Service, which had been created the previous year. Hundreds of structures have been built and are protected for their architectural and historical significance, and researchers have examined more than 1,000 archaeological sites.

In photography, the golden hour (sometimes known as magic hour, especially in cinematography) is the first and last hour of sunlight during the day. when a specific photographic effect is achieved due to the quality of the light.

Typically, lighting is softer (more diffuse) and warmer in hue. Shadows are relatively non-existent if the sun is below the horizon. When the sun is near or below the horizon, sunlight travels through more of the atmosphere, reducing the intensity of the direct light, so that more of the illumination comes from indirect light from the sky (Thomas 1973, 9–13), reducing the lighting ratio. More blue light is scattered, so if the sun is present, its light appears more reddish. In addition, the sun's small angle with the horizon produces longer shadows.

“Hour” is used here quite loosely. The character of the lighting is determined by the sun's altitude, and the time for the sun to move from the horizon to a specified altitude depends on a location's latitude and the time of year (Bermingham 2003, 214). In Los Angeles, California, at an hour after sunrise or an hour before sunset, the sun has an altitude of about 10°–12°. For a location closer to the equator, the altitude is greater (or the time less), and for a location farther from the equator, the altitude is less (or the time greater). For a location sufficiently far from the equator, the sun may not reach an altitude of 10°, and the golden hour lasts for the entire day in certain seasons.

Nature photography refers to a wide range of photography taken outdoors and devoted to displaying natural elements such as landscapes, wildlife, plants, and close-ups of natural scenes and textures. Nature photography tends to put a stronger emphasis on the aesthetic value of the photo than other photography genres, such as photojournalism and documentary photography.

Nature photographs are published in scientific, travel and cultural magazines such as National Geographic Magazine, National Wildlife Magazine and Audubon Magazine or other more specific magazines such as Outdoor Photographer and Nature's Best Photography. Well known nature photographers include Frans Lanting, Galen Rowell, Eliot Porter and Art Wolfe.