An animation shows how the seasons change with the Earth’s orbit around the sun.
The angle of the Earth causes very specific weather patterns and daylight over the course of a year.
Most places experience four seasons, but they are not as pronounced near the equator.
Astronomers believe that billions of years ago, a Mars-sized object crashed into Earth, flipping our planet and leaving it tilted.
This ancient hump is the source of Earth’s seasons – times of the year that have very specific weather patterns and hours of daylight that vary with latitude.
Most places experience four notable seasons: spring, summer, fall, and winter. Below, see how the seasons change with Earth’s orbit around the Sun:
Eleanor Lutz, who is currently a Graphics Editor at The New York Times, made the animation in 2019 using open data from NASA, USGS, and Natural Earth.
“I’ve always been very interested in designs that combine science and art. When I learned to code as part of my PhD in biology, I also wanted to apply coding to my design work,” said Lutz told Insider. “I decided to create a series of astronomy maps because there is a lot of wonderful open-source data in the astronomy community.”
The graph shows how seasonal changes in precipitation and temperature affect Earth’s ice, vegetation, cloud cover, and sunlight.
Earth’s tilt relative to the sun determines the seasons
The Earth is currently tilted 23.4 degrees from the plane where most objects in the solar system orbit the sun, NASA explains. This means that as our planet moves in a nearly circular orbit around the sun, different parts of the globe receive different amounts of sunlight over the course of a year.
The Earth is divided into a northern hemisphere and a southern hemisphere by an imaginary ring called the equator. When the northern hemisphere bends towards the sun in June, it experiences summer. This is when the sun’s rays hit this part of the Earth more directly, heating the Earth’s surface. When it is summer in the northern hemisphere, it is winter in the southern hemisphere.
Six months later, in December, the situation is reversed: the northern hemisphere is tilted away from the sun and experiences a winter climate.
The tilt of the Earth’s axis also defines the duration of daylight hours, which are the shortest during winter in each hemisphere. It’s most dramatic at the planet’s poles, above the Arctic Circle.
In Utqiaġvik, Alaska, the northernmost city in the United States, darkness lasts from mid-November to mid-January.
Near the equator, the seasons are less pronounced, as each day the sun strikes at roughly the same angle. There, the length of the day stays at almost 12 hours in all seasons.
Earth’s tilt angle is relatively stable, but there are some slight shifts on large time scales (tens of thousands of years). According to NASA, the angle is slowly decreasing.
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