Earth Reaches Perihelion: Will It Affect Seasonal Changes?

Like every year, the Earth is having its close contact with the Sun. The phenomenon happens annually, just around the beginning of the new calendar year. Since the Earth travels in an elliptical orbit, its distance the Sun changes throughout its year-long journey. Now the Earth has reached perihelion, the term used for the closest approach to the Sun.

On average, the Earth is about 149,597,870 km away from the Sun. But the annual perihelion event has the Earth positioned about 147,091,144 km away from the Sun. Exactly after half a year from now, the Earth will reach aphelion, when it is most distant from the Sun. During the aphelion stage, the distance between the Sun and the Earth will be 152,095,295 km.

Earth Reaches Perihelion: What To Expect

The perihelion event doesn't make the Earth feel warmer for those in the Northern Hemisphere. The reason is that the ellipse in which our planet orbits is not extreme, but largely circular. In other words, the Earth's axis determines the change in the seasons. However, the perihelion and the aphelion affect the length of the seasons.

Another interesting factor is that the Earth's close approach to the Sun causes it to travel slightly faster. This means a shorter duration for winter in the Northern Hemisphere and shorter summer in the Southern Hemisphere. According to the stats provided by EarthSky, the winters in the Northern Hemisphere are about five days shorter than the summer, and summers in the Southern Hemisphere are five days shorter than winter.

At the same time, the report points out that the Earth seasons are controlled by the axis and not by the distance from the Sun. "... When you take into account that difference in distance between aphelion and perihelion, there's only about a 7 percent difference in average global [solar energy] that we receive. And so it doesn't amount to a great deal in terms of weather," says Walter Petersen, a research physical scientist in the Earth science branch at NASA's Marshall Space Flight Center.