Everyday Einstein explores 3 lies students often learn in school and the true facts behind them.
Why We Have Seasons
Ancient Greeks knew that the reason for the winter season was because for six months of the year Persephone, daughter of the harvest goddess Demeter, was in the underworld with her husband Hades. Mother and daughter missed each other so much during this time that the world languished in cold barrenness until they were reunited in the spring.
Had the Greeks gone to the trouble of visiting the southern hemisphere, they would have seen that perhaps southern Demeter didn’t love her daughter as much as northern Demeter did, because when it's winter in the northern hemisphere, the southern hemisphere is experiencing summer time.
See also: When to Capitalize Seasons
An equally incorrect account of seasonal change taught to many of us is that in the winter the Earth is further from the sun…or at least the top half of the Earth is…somehow…even though it’s a ball…and connected to the bottom half…hmm.
In fact you might be surprised to learn that the Earth is actually furthest from the sun at the beginning of July, around 152 million km away, while in December it reaches its closest point to the sun, around 147 million km away. So what gives?
The real reason we have seasons is because Earth is tilted on its axis. During summertime in the northern hemisphere, the axial tilt is towards the sun, which results in the sun’s rays being able to strike the northern half of the planet more directly and for a longer amount of time than in the southern hemisphere.
During wintertime, the Earth is titled the other way, so the sun appears lower in the sky. This also causes the sun’s rays to be more spread out, and the amount of time those rays strike the Earth is shorter.
So now you know the truth about why airplanes fly, what causes different seasons, and how evolution works. The next time you’re flying in an airplane in the summertime watching Jurassic Park, be confident in the fact that you will be one of the few people who really knows what’s going on.
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