The term night sky refers to the sky as seen at night. The term is usually associated with astronomy, with reference to views of celestial bodies such as stars, the Moon, and planets that become visible on a clear night after the Sun has set. Natural light sources in a night sky include moonlight, starlight, and airglow, depending on location and timing.

The night sky and studies of it have a historical place in both ancient and modern cultures. In the past, for instance, farmers have used the state of the night sky as a calendar to determine when to plant crops. Many cultures have drawn constellations between stars in the sky, using them in association with legends and mythology about their deities.

The anciently developed belief of astrology is generally based on the belief that relationships between heavenly bodies influence or convey information about events on Earth. The scientific study of the night sky and bodies observed within it, meanwhile, takes place in the science of astronomy.

Night or nighttime is the period of time between the sunset and the sunrise when the Sun is below the horizon. This occurs after dusk. The opposite of night is day (or "daytime" to distinguish it from "day" as used for a 24-hour period). The start and end points of time of a night vary based on factors such as season, latitude, longitude and timezone.

At any given time, one side of the planet Earth is bathed in light from the Sun (the daytime) and the other side of the Earth is in the shadow caused by the Earth blocking the light of the sun. This shadow is what we call the darkness of night. Natural illumination is still provided by a combination of moonlight, planetary light, starlight, diffuse zodiacal light, gegenschein, and airglow. In some circumstances, bioluminescence, aurorae and lightning can provide some illumination. The glow provided by artificial illumination is sometimes referred to as light pollution because it can interfere with observational astronomy and ecosystems.

The sky, also known as the celestial dome, commonly refers to everything that lies a certain distance above the surface of Earth, including the atmosphere and the rest of outer space. In the field of astronomy, the sky is also called the celestial sphere. This is an imaginary dome where the sun, stars, planets, and the moon are seen to be traveling. The celestial sphere is divided into regions called constellations. Usually, the term sky is used from the point of view of the Earth's surface. However, the exact meaning of the term can vary; in some cases, the sky is defined as only the denser portions of the atmosphere, for example.

During daylight, the sky appears to be blue because air scatters blue sunlight more than it scatters red. At night, the sky appears to be a mostly dark surface or region scattered with stars. During the day, the Sun can be seen in the sky, unless obscured by clouds. In the night sky (and to some extent during the day) the moon, planets and stars are visible in the sky. Some of the natural phenomena seen in the sky are clouds, rainbows, and aurorae. Lightning and precipitation can also be seen in the sky during storms. Birds, insects, aircraft, and kites are often considered to fly in the sky. As a result of human activities, smog during the day and light pollution during the night are often seen above large cities.

Andrew Wegman Bird (born July 11, 1973) is an American musician, songwriter, and multi-instrumentalist.

Trained in the Suzuki method from the age of four, Bird graduated from Lake Forest High School in 1991 and Northwestern University with a bachelor's degree in violin performance in 1996. That same year he self-released his first solo album, Music of Hair. Vastly different from his later work, this album showcased his violin skills and paid tribute to his fascination with both American and European folk traditions, as well as jazz and blues. Following this, his initial commercial exposure came through collaborative work with the band Squirrel Nut Zippers, appearing on three of their albums (Hot, Sold Out, and Perennial Favorites) between 1996 and 1998.

Taking on the role of bandleader, Bird released Thrills on Rykodisc in 1997 with his group Andrew Bird's Bowl of Fire, shortly followed by second album Oh! The Grandeur in 1998. Both albums were heavily influenced by traditional folk, pre-war jazz, and swing, with Bird relying on the violin as his primary musical instrument, as well as providing vocals along with his trademark verbose lyrics. The Bowl of Fire featured musicians from Bird's home town of Chicago, including Kevin O'Donnell, Joshua Hirsch, Nora O'Connor, Andy Hopkins, Jimmy Sutton, Colin Bunn, and Ryan Hembrey. During this period, Andrew Bird was a member of the jazz group Kevin O'Donnells Quality Six, for which he was the lead singer and violinist and contributed to arrangements and songwriting for the albums Heretic Blues (Delmark 1999) and Control Freak (Delmark 2000) (both Delmark albums were produced by Raymond Salvatore Harmon).