Northern Hemisphere

"In the Northern Hemisphere, my village and my country, like most of us humans, are located in there, in the Northern Hemisphere. Most of the battles in World War III took place in the Northern Hemisphere. So, what's next, will it spread to the Southern Hemisphere by crossing the equator?"

--Su Ji-Hoon, The Fate of the Northern Hemisphere

The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's North pole.

Owing to the Earth's axial tilt, winter in the Northern Hemisphere lasts from the December solstice (typically December 21 UTC) to the March equinox (typically March 20 UTC), while summer lasts from the June solstice (typically June 21 UTC) through to the September equinox (typically September 23 UTC). The dates vary each year due to the difference between the calendar year and the astronomical year.