This effect, known as gravitational redshift, leads to a tiny shift of atoms' internal energy levels depending on their ...

In 1995, Butterfield Jewelers prepared for daylight saving weeks in advance. Employees manually wound hundreds of watches, ...

Daylight saving time starts on Sunday when the clocks spring forward. Most of the United States will see a later sunset, ...

The body's internal clock doesn't just dictate when we sleep - it also determines how quickly our muscles heal.

Congress has tried – and failed – to make daylight saving time the permanent standard on clocks across the country.