The Mechanics of Earth's Spin Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hours, 56 ...

Day and night will get equal time for a brief moment Monday as much of the world heads into fall. The autumnal equinox arrives Monday, marking the start of the fall season for the Northern Hemisphere ...

Researchers have discovered a change in what scientists already knew about global warming dynamics. It had been widely accepted since the 1950s that global temperature rises were not consistent ...