The axis on which Earth rotates is tilted by 23.5°, which can easily be seen if you take a series of … [+]
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Do the seasons explain why Earth is teeming with life?
The axis on which Earth rotates is tilted by 23.5°—likely caused by an impact billions of years ago—which during our annual orbit around the Sun means that different parts of Earth receive sunlight for different lengths of time.
Cue Earth’s seasons, solstices, equinoxes … and life?
It’s long been thought that it’s the distance from its star that determines how likely it is for a planet to host life.
The theory goes that there’s a not-too-warm, not-too-cold, but just right “Goldilocks zone” within which liquid water can exist on the surface of a planet.