Biggest North Pole mission back from 'dying Arctic'

Researchers on the world's biggest mission to the North Pole returned to Germany on Monday, bringing home devastating proof of a dying Arctic Ocean and warnings of ice-free summers in just decades.

Arctic odyssey ends, bringing home tales of alarming ice loss

The biggest Arctic expedition in history will return to the German port of Bremerhaven on Monday after a year-long mission, bringing home observations from scientists that sea ice is melting at a "dramatic rate" in the region.

Scientists observe bacteria tumble their way out of surface traps

While tracing the movement of Escherichia coli, a team of French researchers noticed that near solid surfaces, the bacteria run in circles. Loop after loop, the tracing almost looks like an Olympic figure skating rink before ...

Image: Hubble hooks a one-arm galaxy

NGC 4618 was discovered on April 9, 1787, by the German-British astronomer William Herschel, who also discovered Uranus in 1781. Only a year before discovering NGC 4618, Herschel theorized that the "foggy" objects astronomers ...

This wearable device camouflages its wearer no matter the weather

Researchers at the University of California San Diego developed a wearable technology that can hide its wearer from heat-detecting sensors such as night vision goggles, even when the ambient temperature changes—a feat that ...

The genetic secret of night vision

One of the most remarkable characteristics of the vertebrate eye is its retina. Surprisingly, the sensitive portions of the photoreceptor cells are found on the hind side of the retina, meaning that light needs to travel ...

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Night

Night or nighttime is the period of time 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 times of 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.

This text uses material from Wikipedia, licensed under CC BY-SA