The fall equinox comes this Wednesday at 3:21 p.m. ET. The day heralds the start of autumn in the northern hemisphere, which houses about 90% of Earth's population. For the southern hemisphere ...

During an equinox the Earth's north and south poles are not tilted towards or away from the sun, which also means the duration of daylight is almost the same at all points on the Earth's surface.

This is when the sun passed over the equator or the equator was the closest part of Earth to the sun, the exact moment being 21:59 GMT. The term equinox means "equal night," when day and night are ...

What is the equinox? During the spring and fall equinoxes, the Earth’s axis and its orbit ... The Associated Press Health and Science Department receives support from the Howard Hughes Medical ...

The word equinox comes from two Latin words meaning ... Astronomical seasons depend on how the Earth moves around the sun. Solstices kick off summer and winter. Equinoxes mark the start of spring and ...

It also signals the arrival of summer and a gradual advance toward fall, the start of which is marked by an equinox. Two things drive this all-important seasonal shuffle: Earth's tilted axis and ...